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    FAQ or Answers to Frequently Asked Questions                  Section 29
          Please check "root" (faq$txt) file for acknowledgements. 
    This is a file containing answers, tips, hints and guidelines associated 
    with recurring  questions asked by photographers.   If you would like to 
    add a tidbit of knowledge to  this list just send it to   ANDPPH@rit.edu 
    who will gladly add it to this collection. For complete table of content
    send message to   ritphoto@rit.edu   with  FAQ$txt  in the Subject: line
                    These files are available in SECTIONS. 
             This is Section 29 and its contents are listed below.
      29.1   -< Where to process Infrared Color Film >- 
      29.2   -< 3D Processing and Finishing Laboratories >-
      29.3   -< Star Trail Control with Exposure Time >-
      29.4   -< Problem with Glass Carriers and Rings on Prints >-
      29.5   -< Black Light  >-
      29.6   -< Minox Cameras Dated and Described >- 
      29.7   -< Filter Primer >-
      29.8   -< Is Photography a Language? >- 
      29.9   -< Hundreds of Film/Developer Processing Instructions >-
Note 29.1         -< Where to process Infrared Color Film >- 
>>Anyone know who develops color infrared film? Seems near impossible to get
>>it done anywhere.
Rocky Mountain Film Lab       or     Johns Hopkins School of Medicine
145 Madison Street                   Raymond Lund, RBP, FBPA 
Denver, CO 80206                     Monumnet and Wolf Streets
303-399-6444                         Baltimore, MD 21205 
maybe also, 
Precision Photo Laboratories         University of Guelph Illustration Svcs.
5758 N. Webster Street               Guelph
Dayton, OH 45414                     Ontario, N1G 2W1, CANADA
513-898-7450                         519-824-4120 ext 3641
American Photo Group                 Buffalo General Hospital Photo Dept.
616 Dwight Street                    100 High Street
Springfield, MA 01103                Buffalo, NY 14230
413-739-2521                         716-845-2863 (call before sending film)
Kolor Print Inc.                     Lightwork Labs
2121 Thayer Street,                  509 NW 10th Avenue
Box 747-72203                        Gainesville, FL 32601
Little Rock, AR 72202                904-376-9745
from: andrew davidhazy, andpph@rit.edu
Note 29.2       -< 3D Processing and Finishing Laboratories >-
>Where does one send film exposed in a Nishika or Nimslo camera for
To have film developed and printed into 3D lenticular prints there may be only
one option left as of March 2002. This is the Orasee Corproation. They may also 
do "custom" work I believe as well as enlargements.
    Orasee Corporation
    4850 Green River Parkway
    Duluth, GA 30096

    ph: 770-497-0727
    fx: 770-497-0724

Find their website at: http://www.orasee.com/new/film_processing.php3
from: andy davidhazy, andpph@rit.edu 
Note 29.3         -< Star Trail Control with Exposure Time >-
>I photographed the Orion stars last week and one of the pics had star trails 
>rather than star spot. What is the maximum time allowable to prevent the stars
>from trailing? I used a 200mm lens pointing it about 30 degrees from zenith.
This is an interesting question since while the angular speed of the stars is
the same, roughly 15 degrees per hour, their effective speed on the film varies
with elevation. I do not have the answer but am going to try figuring it out.
Suppose the camera is aimed low to the horizon then the lens will record an
angle in the sky equal to its angle of coverage. For a 50 mm lens horizontally 
this is about 40 degrees, a 100 20 degrees and a 200 10 degrees. The stars 
appear to move at 15 degrees per hour or 15/60 or .25 degrees per minute or 
.25/60  or .0042 degrees per second. So, using a 50mm lens, a star's image will 
move across the frame in 40 degrees /.0042 degrees per second = 9600 seconds
So how many star images are there in 40 mm? at 100 stars per mm there would be
roughly 4,000 so in one second you'd have to "cover" about 1/2 stars worth.
If your criterion says that you have to restrict motion to a "blob" one star
tall by four or five stars long then you'd have to have a maximum exposure 
time of 8 seconds. Exposure times longer than about 10 seconds will already 
show significant trailing. Ultimately it really depends on how much blur you
can allow. If you can only allow motion equivalent to one star's image diameter
on the film your exposure time requirements will be much more stringent than if
you can allow the star's image to move two, three or more diameters before you
consider it a trail instead of a spot.
Now if you raise the angle of the camera towards the poles then the effective
speed of the images will be less ... or another way to say it is that you will
cover more "degrees" of the sky with the same lens. Essentially with the camera
pointed at the pole star you will cover 360 degrees around the pole star (with
any lens!) and there will be very little motion at all in this region and much
longer exposures can be tolerated.    
Anyway, this means that you can probably use longer and longer times as the
elevation of the stars approaches the pole stars. If your stars are within 30
degrees of the pole star you can probably roughly double or maybe even
quadruple the time you'd use at 90 degrees to the pole star.
I'm going to assume a linear relationship between image velocity and focal
length and thus if for a 50 mm lens at the celestial equator I need to use a
time 8 seconds with a 50 then in the same region I'd need to use 4 seconds
with a 100 and 2 seconds with a 200.
Tilting the camera towards the pole star may allow a time let's say 4 times as
long so for a 50mm lens that would be 24 seconds, a 100mm lens 12 seconds and 
for a 200mm lens it would be about 6 seconds.
Please note that I am placing this here more as a point of discussion rather
than as an absolute and correct answer to the question posed by Magnus above.
andy, andpph@rit.edu, at RIT's High Speed Photography Lab
From: ben@lonestar.jpl.utsa.edu (Ben A. Fairbank)
Subject: Re:  Star Trails
Organization: University of Texas at San Antonio
An earlier poster, message deleted inadvertantly, asked about the exposure time
necessary to avoid star "trails" when making star photographs.  He or she
mentioned that he/she was shooting about 30 degrees from the zenith.
The answer depends on a number of factors; rather than posting an answer that
might be wrong for the case you are interested in, let me explain one way to
figure your own answer, at least as a starting point.  You can use the answer
you calculate as an approximation and make test shots starting there.  First,
the distance from the zenith (straight up) of your picture is not relevant
unless you also give your latitude and the direction you are shooting.  Even
then the calculation is nontrivial.  The really important figure is how far
from the north celestial pole you are shooting.
Let us calculate for the worst case -- that for stars on the celestial equator
(worst because they will always move the fastest, regardless of how far they
are from the zenith).  Start from the final product -- the prints you will
make.  How big will they be?  Eleven by fourteen?  OK, now, since all star
pictures made with a camera that does not follow the stars will be tracks, not
points, what is the longest track that is acceptable to you in your 11 x 14
prints?  One millimeter,  you say.  Okay, now slate that to your negative.  Let
us assume, again for simplicity, that you are using a 35 mm camera and printing
the full frame.  That means you will be enlarging about ten times so that the
longest star track that is acceptable on the negative is 0.1 mm.  It is now
necessary to translate that into an angular measurement -- a measurement of how
far across the sky, in degrees or minutes of angle, the star moves during your
exposure.  You specified a 200 mm lens, so we can calculate the tangent
(remember from your trig that the tangent is the opposite side divided by the
adjacent side of the triangle as "seen" by the angle of interest) of the angle
as being (0.1/200), which is 0.0005. (Purists:  I know that this involves a
slight simplification, but it agrees with the true value to seven significant
figures...)  Now find the arctangent of 0.0005, which is 0.0286 degrees, or 1.7
minutes of angle. The problem now is to find how long it takes for the
celestial sphere to rotate 1.7 minutes of angle.  The earth rotates 360 degrees
in 24 hours or 15 degrees per hour or 1 degree in 4 minutes or 1 degree in 240
seconds, or sixty minutes of ANGLE in 240 seconds of time or 1 minute of ANGLE
in 4 seconds of time (all equivalent rates).  Thus it would take about 7
seconds for the sphere to rotate 1.7 minutes of angle.  
Therefore, if you want your star trails to be one millimeter or less in length
in an 11 by 14 print from a 35mm negative taken with a 200 mm lens you should
expose no more than 7 seconds on the celestial equator.  You can modify the
prodecure depending on your requirements, but the general method will remain
the same.                                                   
From: ben@lonestar.jpl.utsa.edu (Ben A. Fairbank)
Subject: Re:  Star Tracks (again)
Organization: University of Texas at San Antonio
This is a shorter but more practical version of my earlier post in in answer to
the question of how long one may expose pictures of stars  in order for the
stars to appear as points, not lines.
The star images will always be lines if the camera does not follow the stars,
so the question will always be "How long a line can you  tolerate in the
finished print?"  If you know how long a line you can tolerate, then figuring
the exposure time is straightforward.  The following five variables are
E = degree of Enlargement (for example, enlarging a 35 mm negative
    to an 8x10 print involves an E factor of 8) planned for final
    print of the negative
L = Length of longest permissible star track in final print (this is
    measured in millimeters)
F = Focal length of taking lens (again, measured in millimeters)
D = angular Distance from celestial equator to the star in the 
    photo which will be nearest the equator (this is known as 
    the star's declination)
T = maximum exposure Time which will guarantee that the tracks will
    be no longer than L.
The formula is
  T = 240 * Arctan (L / (E * F)) / (Cos D)
If, as is often the case, you do not know the value of D, then just  ignore the
division by Cos D.  This will have the effect of giving the exposure time
appropriate for stars on the equator, which are the  fastest-moving of all
stars.  Any off-equator stars will move more slowly and so will make tracks
even shorter than your maximum  acceptable length.
If you are making a 4 by 6 print of a picture taken with a 50 mm lens on 35 mm
film, with the closest star to the equator  being 40 degrees from the equator
and a maximum permissible star  trail length of 1 mm, then your maximum
exposure would be 90 seconds.  
If you were making an 11 by 14 enlargement of a 35 mm negative  taken with a
200 mm lens of stars on the celestial equator and could  tolerate a 1 mm trail
length, then your maximum exposure would  be about 6 seconds.
DISCLAIMER -- This equation was derived from simple geometric and astronomical
princples, but since I am not an astronomer (except an  amateur one), it may
still be wrong.  See article by James V.  Bradley entitled "Overconfidence in
Ignorant Experts."
Ben Fairbank.
and from Michael Gudzinowicz:
Estimating the length of a star trail is fairly simple. First  calculate
the rate of angular motion... 24 hr/day X 60 =  1440 minutes X 60 sec =
86400 sec; 360 deg / 86400 sec = 0.00417 deg/sec. One can include a factor
for the position of  a star in relation to the axis of rotation... let A be
the  angle between the pole star and the star of interest. Then the 
angular rate approximates (sin A)*(0.00417) deg/sec. 
For small angles, the tangent and sine are very nearly  proportional to the
angle, so one may substitute the rate of  change of the tangent of the
angle swept by the earth's  rotation, giving rate tan/sec = (sin
The tangent of the angle is the film_streak_length /  focal_length. So
during time = T,
streak_length/focal_length = T * (sin A)*(0.0000727)/sec or
T = film_streak_length / ((focal_length)*(sin A)*(0.0000727).
(Close approximation).
If one wishes to make a "sharp" 8X enlargement from 35 mm, the circle of
confusion (0.03 mm) can be substituted for the streak_length. Using a 100
mm lens, 90 deg from the pole star, the maximum exposure time is
approximately 4.1 seconds. For longer lenses or larger prints, the time is
shorter. For wider lenses or angles closer to the axis of rotation,
exposure times can be longer.
With the pole star in the frame for long exposures, it is  apparent that
trails form arcs with the star at the  approximate center. The arc angle
increases at the rate of 15  deg per hour... a 90 deg arc requires a 6 hr
exposure (use  films with high reciprocity failure to prevent sky fog).
(Note that a number of assumptions were made in determining  the rate of
motion on the film plane, but the errors  introduced are relatively small
considering the intended  purpose of the calculation.) 
Mike in RI / Internet: ab366@osfn.rhilinet.gov
    and here is yet another contribution to determining star-trail and
    exposure time relationship:
length of star trail on the film:
l_film = 7.3 x 10^-5 * focal length in mm * exp time in sec * cos(declination)
where declination is of course 0 at the celestial equator and +/- 90 deg
at the celestial poles. Zenith angle doesn't matter.
Compare to conventional choice of say 0.03 mm as acceptable circle of
confusion for 35mm format. (Any good lens will do better than 0.03 mm
I would imagine.)
That number, 7.3 x 10^-5, is from 15 arcsec per second of time (earth's
rotation) and 206265 arcsec in one radian, if anyone cares.
From: Ben Weiner, bweiner@electron.rutgers.edu at Rutgers University
and another:

I finally found the right book:
          Skyshooting: Hunting the Stars with your Camera
         R.N. Mayall & M.L. Mayall, 1949
         New York, The Ronald Press Company
 The length of any star trail is found by the formula on page 17:
     T = 2pi * F * (t / N), where:
          T = length of trail of an equatorial star
          2pi = 6.28
          F = focl length of the lense
          t = exposure time (in seconds, minutes, or hours)
          N = number of seconds, minutes or hours in one day
               1 day = 24 hours = 1440 minutes = 86400 seconds
If my math is correct, a star trail of 0.1 mm length (which will look like a 
dot) requires a maximum of 10.2 seconds on a 135mm lense and 27.5 seconds on 
a 50 mm lens.  
Of course, the film speed, the **seeing** and the f/stop will determine 
how bright each dot will be (how many stars, or how faint a star, will be 
Fred Gunther, 

Note 29.4    -< Problem with Glass Carriers and Rings on Prints >-
>Sometimes when printing negatives with a glass carrier I notice faint rings
>of density spread all over my prints. I have noticed this also in my Leitz
>Focomat enlarger where the condenser comes in contact with the film. Why?
The problem is caused by Newton's rings, a light interference effect that
shows up when two very smooth surfaces come in close proximity to each other
causing light rays to constructively or destructively interfere with each
other. Where there is constructive interference you will perceive a dark band 
on your print and a lighter, underexposed, band where there is destructive
The problem can be overcome to some extent by spreading anti-newton powder
between the offending surfaces or using glass that has a slightly roughened
surface. This is regularly used by makers of glass slide mounts. The powder 
can be obtained at Graphic Arts suppliers. I have never used it myself.
To overcome this problem in your enlarger use anti-newton glass in the carrier 
or add an anti-newton glass spacer below the Focomat's condenser. There is a
likelihood that the pattern etched into the anti-newton glass may show up as a
faint texture in your prints however.
For small film sizes you might simply use anti-newton glass from a slide mount.
For larger sizes Condit Mfg. Company sells anti-newton glass in various sizes. 
They not only sell anti-newton glass but also pin-registartion equipment useful
for special-effects work. They are at: Condit Mfg. Co. Inc., 29 Philo Curtis 
Rd., Sandy Hook, CT  06482, (203) 426-4119 (Warren L. Condit is the President)
Note 29.5                     -< Black Light  >-
>Pardon my ignorance but I am a self taught/teaching novice. What is a black 
>light? What is it used for in general?  With exposure of approx1/4sec, what 
>aperture was used? I'm interested in learning and experimenting.
Black light is the colloquial term for Ultraviolet rays (as opposed to
"light" rays which we can see). UV is energy of shorter wavelength than
reds, greens or  blues. UV is invisible but some sources such as used in
concert admission validation stations are almost visible. They are called
"long wave" UV sources. There is also short wave UV which is dangerous to
your health and is responsible for the tanning effect of sunlight. 
The term "black light"is often associated with illuminating a subject with
"black" (invisible or nearly so) light and viewing its transformation by
certain substances to longer wavelength rays which are relatively easily
visible. This effect is called fluorescence. Fluorescence can appear as
light of various colors depending on the "transformation" quality of the
material illuminated by the UV. It is best perceived when there is very
little light present.
Since under these conditions the eye's pupils are wide open and the
retina's effective "speed" is increased to a maximum, even small levels of
fluorescence (which is typically the case) are easily seen ... but are
relatively difficult to photograph. Thus typically there is a need for
large lens apertures and fast films. Apertures of maybe f:2, film speeds
in the 400 ISO range and exposure times in the 1 to 1/8 second range using
fluorescent tubes emitting mostly long wave UV "light". Since the power of
these tubes is hardly standardized it is really difficult to give
definitive exposure guidelines.
A good place to see dramatic color effects caused by UV excited
fluorescence is your local science museum in the minerals division. If you
are photographing this phenomenon it is best to use a slight yellow filter
such as a Wratten 2E because this will prevent the UV rays from causing un
"unnatural" bluish cast on your color films. The 2E filter should be used
even though to the eye the colors are not contaminated by excess blue.
This is because the eye is not affected by the presence of UV being
insensitive to it but color films may respond to the excess UV present
(even though some films have a UV blocking filter layer coated as the top
layer on the emulsion.
If you are interested in further reading on this subject you could check
out the articles available from the following address:  ritphoto@rit.edu
andy  o o  0 0 o   o  Andrew Davidhazy, at RIT's Imaging and Photo Tech Dept
       \/\/\/\/\/\/   andpph@rit.edu              High Speed Photography Lab
________|        |__________________________________________________________
Note 29.6           -< Minox Cameras Dated and Described >- 
Minox Subminiature Camera Models List (1.1)
Authors: Bennett Todd 
         Bob Salomon  
This is a preliminary draft. I'd appreciate corrections and additions. I figure
this might be helpful to people considering buying a used submini, or just
curious about their history. Anyone seriously interested in Minox subminis
should definitely buy and read "Spycamera -- the Minox Story", by Morris
Moses (1990, Hove Foto Books, ISBN 0-906447-43-7). While I didn't copy this
out of Moses or anything, I definitely learned more from that book than from
everything else put together.
If I get enough positive feedback (including additions and corrections!) may
try to shove this into the FAQ repository.
All Minox subminis are viewfinder cameras with a fixed-focal-length 15mm
lens, which has a similar FOV on the 8x11mm negative to a 50mm lens on a 35mm
camera. Except for the EC, all are manual focus (8" to infinity) f/3.5. The
EC's lens is fixed-focus (six feet to infinity) f/5.6. They all take the same
film cartridge, a daylight-loading affair, still available. Minox now has
Ektar 25, whose resolution helps make up for the small negative format. All
except the EC focus down to 8", and have parallax-corrected viewfinders for the
close-focusing. Besides uses for document duplicating, this is handy for other
macro shots. For instance, a Minox submini makes a _great_ camera to take to an
orchid show.
The models:
Original "Riga": stainless-steel case. Original lens; not as sharp near the
  edges of the frame as later lenses. This is the only stainless-steel bodied
  model; it's the heaviest, and the least-likely to be dinged. Highly-prized
  collector's item; tends to go for >$2,000. Made in Riga, Latvia.
Minox II: like all post-WWII Minoxes, aluminum-bodied. Made in Wetzlar,
  Germany. Different lens design from Riga; rear element of lens actually
  touches film surface, leading to problems with scratching.
Minox III: new lens design, essentially the same as all later Minoxes (except
  the EC), called the "complan". Still completely manual with no meter; this
  and later models are all fine shooters.
Minox IIIs: just like the III, with a flash synch (PC connector).
Minox B: First Minox bigger than all the previous. This one is a bit longer,
  and adds a selenium cell light meter. You still set the shutter speed by
Minox C: still longer than the B; this one is the biggest Minox submini; where
  a IIIs is about 3-1/4" including PC flash connector, the C is about 4-1/2"
  long. This is the first Minox submini with Auto-Exposure; it has a CdS cell
  light meter, which can control the shutter speed (which can also be manually
  set). You _can't_ tell what speed the meter is gonna use. This is the first
  Minox submini to require a battery.
  Later models of C, as well as the LX, have a modified complan lens, changed
  to focus on a flat plane rather than a curved one. So, they have a flat
  pressure plate. The best prints are made if you use an enlarger with a flat
  or curved film holder to match the flat or curved pressure plate in your
Minox LX: current manufacture; shorter than the C (but larger than the
  originals); auto-exposure, as well as manual. The first Minox whose shutter
  speed goes up to 1/2000.
Minox EC: also current, this is targetted as a mass-market point-and-shoot,
  with a fixed-focus lens that focuses 6 feet to infinity.
Somewhere in these last few models (I'm not sure where) the Minox factory moved
from Wetzlar to Giesen, Germany.
Note 29.7               -< Filter Primer >-
FILTERS: The Basics
Peter Bryenton, (C) February 1995 (except for personal use).
Filters work by changing light into heat as energy passes through
The idea of a filter is simple enough. If you go down to your
favourite burger bar and place an order, you'll get what it shows
on the menu photograph. If you don't want everything that way,
you just ask for something to be changed - usually customers
want an item left out. Suppose you don't like mayonnaise. It is
easy to say "Please don't put any mayonnaise on my burger" if
you are in England. In America I guess that shouting "hold the
mayo" probably gets the same result, which is a burger which
has been made specially to order.
So it is with the filters used in photgraphy. There is a starting
point, which is made up of the filter itself and the light source
which must pass through it. What comes out is light which has
been modifed by the filter. Something you did not want in the
light has been taken away (subtracted).
A blue filter (one that looks blue when you hold it up to your
eye) takes part of the incoming light energy away by changing it
into heat on its way through. The bits it removes are the colours
we see as greens and reds. When our eye-brain systems see red
and green light mixed together we get the impression of yellow
(All the colours you see on your TV set are really coming to
your eye from just three sets of tiny dots of light which are red,
green and blue. Check this out with a magnifying glass).
A blue filter is sometimes called a "minus yellow" filter to show
its action more clearly. In black and white photography, using a
panchromatic emulsion ("pan" film) means that the film records
all the visible colours of the spectrum (look at a  rainbow to see
them). The film "sees" everything, though not necessarily exactly
the way we do. 
If you want your final monochrome print to show an originally
blue sky as being darker in tone than it would be shown by the
straight film itself, you can take away some of the blue light in
the sky by placing a yellow filter over your lens at the taking
stage. This method works the other way round from the
explanation above; here the yellow filter works as a minus blue
filter and only lets the red and green through. Red and green are
seen by both pan films (like T-Max) and people as yellow and
that is exactly what the glass looks like to our eye.
Taking light away is the same as reducing the exposure in the
camera, (have you ever shot with a lens cap on ?) so you end up
with a darker (underexposed) sky. Because this filter allows
greens and reds through almost unchanged (nothing is perfect
and there will always be a slight loss), green grass and red
flowers in a landscape will get almost the same exposure they
would have done without the filter being used at all.
What making the right choice of filters can do for you is to give
you more control over different areas of the same image at the
taking stage. Used effectively, filters are a powerful tool in your
box of photographic spanners (wrenches). Maybe you want to try
this for yourself now and start thinking  about why a red
safelight is essential for multigrade printing work but a yellow
one will do just fine for graded papers.
This light-to-heat effect explains why, in theatre lighting for
example, all those dark, deep moody colours burn out so quickly.
There is a lot of subtracting light going on and the heat has to go
somewhere - into the filter material itself. Thankfully the days of
them bursting into flames are over due to the modern
flame-proof plastic bases.
The average glass filter used in front of a camera lens never
meets this problem of course but some photographers like to
filter their tungsten lamps by covering them with gels. If you do
this, remember to leave plenty of room for ventilation and don't
leave them switched on unattended. Models spend a lot of
money on their hair and clothes especially for you. They like to
leave a session with everything they had when it started.
So, next time you eat a Big Mac, why not think about trying a
little creative filtering for your monochrome work? Lemons (the
fruit your bartender cuts up) and deep blue filters can be fun.
Peter Bryenton (C)
BBC Wood Norton, UK
Note 29.8           -< Is Photography a Language? >- 
                       Is photography a language? 
                             J. David Sapir
                          University of Virginia
Talk for Brown University   6 March 1995    copyright by J. David Sapir 1995
Photography can be called a language only if you say that any form of human
communication is a language - dance, music, painting, drawing or sculpture.  
Note: William Crawford, in his Keepers of Light, picks up the concept of
syntax that was used by William Ivins in Prints and Visual Communication:
"conventions or systems of linear structure" used in the "preparation of a
drawn image." Here is a system of organization "used in putting lines together
to form pictures that can stand as representations of particular objects."
Although Ivins considered photography as having no 'syntax,' Crawford in
exploring the many forms of photographic processes that were used in the 19th
century disagrees. A Daguerreotype is distinct from a caleotype and the two
differ from wet plate callodion photographs. 
Consider the frequently reprinted 19th century engraving from Germany (I
believe) a backpacker viewed from the back carrying his photographic
equipment. Crawford titles: 'Wet Plate photographer carrying his syntax on his
consider also the photo of: William Henry Jackson outside of his 'dark tent'
and William Henry Jackson's two assistants (a man and a mule). 
Note:  Alan Sukula mocked the idea of photography being a "universal
language", though he might accept it as a language. 
I don't find it terribly useful to call photography a language. Having at one
point worked out the grammar of an African language, I am hard pressed to see
any useful parallels and anyway would insist on trying to find irregular verbs
in photos, if photography was indeed a language. 
The old distinction made by Susanne Langer in her 1940 Philosophy in a New
Key, is a good place to start. She talked of two types of symbolism (using
symbol in the broad sense, the way Peirce would use sign). Discursive and 
Presentational. Quintessentially language is discursive: it is lineal, it is
atomistic and it is paraphrasable. That is: words are strung out, one after
the next. You don't get the idea until the sentence, or paragraph - chapter,
book is gone through. A sentence can be broken down into words and each word
carries meaning and can be put into a lexicon. And the sense of what is
communicated in language can be communicated by using different words, or a
different order to the words - here is the cat -> the cat is here -> voici  le
chat. Now each point can be disputed, or greatly modified given particular
instances. For example poetry defies paraphrase - although you can explain it
- or try to explain it, a lot is lost, even beyond the disruption of what
Roman Jakobson called the 'poetic function,' the  musicality of verbal sounds.
'If music be the food of love, play on, give me excess of it ... ' Try to
paraphrase that. 
Presentational symbolism - the opposite: here everything together - at once -
it finds its 'meaning' from the entire gestalt. The relation ship of parts to
a whole - where the parts are themselves without meaning. The idea of 
paraphrase does not apply. An image - a drawing, a painting, would be the
quintessential presentational symbol. There would, of course be exceptions.
For example a sequence of images in a set would imply a discourse. 
Photography fits squarely with presentational symbols - on the other side 
from language. So, at this initial point photography and language emphatically
part company, as they would in taxonomies more complex than that of Langer. 
But if there is little point in talking of a photographic language, it becomes
very interesting when we ask ourselves how photography finds its place among
other presentational forms. What kind of image is a photograph? It is not,
primarily, an image at all. It is an index. This we learn from Charles Peirce.
Let me quote the one place where he speaks about photography: 
Photographs, especially instantaneous photographs, are very instructive,
because we know that they are in certain respects exactly like the objects
they represent. But this resemblance is due to the photographs having been
produced under such circumstances that they were physically forced to 
correspond point by point to nature. In that aspect, then, they belong to the
second class of signs [indices], those by physical connection. (Buchler,
I am not exactly sure when he wrote this paragraph, but I am sure it was after
the invention and broad distribution of the Kodak which was introduced in the
It is the photograph's indexicality that determines its uniqueness. Hence, its
interest to semiotics. To deny or ignore a photograph's indexicality, its
trace (as Susan Sontag puts it), is to absorb it into the class of all 
graphic forms - photography becomes one out of a repertoire of image
processes: engraving, lithography, woodcutting, painting, etc. This is
precisely the position taken by commentators who come to photography from the
angle of art: that is, those art critics who have decided that photography  is
an art. In fact, according to some of those critics, it is today's art of
Let us worry the idea of indexicality - and in our discussion we will want to
ask two separate questions: First: when is it important, in fact essential, to
take into account the indexicality of a photograph, and when not.  Secondly,
why are art critics and art photographers disinclined to consider the
indexicality of a photograph. Or, if they consider it, they consider as
something of no great moment.  
The importance of indexicality. We learned from James Frazer that there are
two types of magic: The magic of contagion; which is the magic of things that
are once together, are always together - you work on someone's finger nails or
hair clippings and you work on that person. And the magic of sympathy - things
that are similar to each other are the same. Thus, you burn in effigy the
image of someone you wish to harm. Images - pictures - participate in the
magic of sympathy. Photographs participate in both. 
There are lots of stories about people who believe that a part of themselves
is taken away when they are photographed. These are said to be "primitive"
people. But not just socalled "primitives," back country hayseeds. John
Thomson experienced difficulties making his memorable photographs during his
travels in China in the 1870's. And that great primitive Honore/ de Balzac
thought as much. 'He had a theory .. that each time the shutter clicked a
layer was peeled off the personality of the sitter.' Nadar said of the theory:
'He had nothing to fear; his abdominal contours allowed plenty of latitude for
shedding ghosts.' [There is only a single known daguerreotype of Balzac, owned
at one time by Nadar and used by Rodin for his great sculpture of Balzac.] 
Franz Boas gave this example to show the universality of "primitive thought:" 
I take your photograph - today it would be very simple to take a polaroid -
Your image emerges, I take it, spit on it, crumple it up, toss to the floor
and stamp on it, all the while saying 'horrible picture, horrible picture.'
What is your reaction? 
The double magic of a photograph - its indexicality coupled with its imaging -
presses upon us mainly in one specific variety of photograph: Photographs of
people and this would come up most particularly in family pictures and beyond
them to photographs of, what I like to call 'people in the world'  ...
documentary photographs, photojournalism, street photographs, papparazzi
pictures. Throughout all, the photograph, at an important level, remains
attached to its referent. The referent is omnipresent. 
This, of course, is what fascinated Roland Barthes in his last book, La
Chambre Claire. The link between the photograph and the subject leads him to a
dramatic discussion of the sinister nature of a photograph: a person is
present, but as the photograph was taken at a time in the past, the person is
no longer or, at least, is no longer in the situation and condition as appears
in the photograph. He or she might be dead. Thus he reflects on a photograph
of his mother when she was five years old - a young child full of the energy
of youth. But his mother is dead. Thus he talked of a photograph as
representing the living dead. In his dramatic rhetoric: Photographs are a form
of madness. 
It is the indexicality - the contagion - of a photograph that leads us to say
that a photograph never lies - a picture is worth a thousand words. The
untruth of a photograph does not rest with its indexicality. As Dorothea 
Lange (is said to have) said 'photographs don't lie, but lots of liars take
lots of photographs. 
However - if there is an indexical and mechanical relationship between the
photograph and the subject of the photograph there is also, on the flip side,
a subjective choice, made by the photographer, to take a picture at a  precise
moment and from a precise angle and in a precise light. So here we have a
photographer controlling the recording of a subject's trace. If a photograph
"maps" reality, then the contours of this reality will be chosen by the
photographic "operator." 
But if the photographer controls the action of taking, the  photographer at
the same time is never relieved of the actuality of his/her subject. This, of
course, has ethical  implications, a fact that concerns serious
photojournalists, not to mention family shutterbugs and portrait 
photographers. In taking a picture you owe something to your subject. If you
think otherwise, as does Richard Avedon, your photographs will surely come
back to haunt you. 
What I say applies primarily - if not exclusively - to photographs of human
subjects especially of subjects that present themselves or are taken by the
photographer as photographs of themselves as they are or as they believe
themselves to be. A studio model, paid to comply, would have less involvement.
And of course these issues scarcely arise when the subject is non-human or
inanimate - a rock, a tree, a mountain, or a pepper. You photograph the
pepper, then you eat the pepper, as Edward Weston would do. Although the grand
photographs of the West taken in the latter decades of the 19th century by
Carleton Watkins, William Henry Jackson, Timothy O'Sullivan and others have an
indexical presence which even today is truely thrilling. 
This brings us to the second topic to worry, the disinclination of an art
critic to take into account a photograph's indexicality. 
We learn from Kant that an aesthetic entails a 'pleasure without concept,' and
thus is detached from any moral judgements and practical reason. This, of
course, gives us our 'art for art sake' and to the expressiveness of the 
individual artist. From this angle, if a subject of a photograph maintains an
indexical claim to his or her image, then the artist photographer loses total
claim to the creative process. 
[As an aside. It is fascinating to read - by report or often in how-to manuals
- about the subtle play, theatre really, that evolved between the great 19th
century portrait photographers and their subjects: Southworth and Hawes in
Boston, Nadar and Carjat in Paris, Julia Cameron, Hill and Adamson, Lewis
Carroll in England. We find this today in the Mann Family Theatre Company:
Sally the producer and director; Emmett, Jessie and Virginia the script
writers and actors.]  
When the referent persists, resisting transcendence, the photographic work of
art becomes entailed, it is forever contingent. This will not do, and such a
relationship must be brushed aside or, more likely, simply ignored. 
Or - if an indexicality is admitted as part of the basic photographic process
- it is purposely obliterated. This is where 'art photography' seems mainly to
be at this moment. Many processes are available to relieve a photograph of any
recalcitrant ties to the world. There are forms of manipulation that have been
available for many years: combination photographs - photographs made up of
many separate photographs - complex processes that overlay a photograph with
various gums and sticky inks and other substances or by simply painting over a
photographic base. The possibilities are many. 
But the top of the list and the most talked about is the manipulation of
photographic material by way of computer processing. The possibilities are
limitless and I shall not go into them for I am sure you are familiar with
what can be done. I will, however, mention the vocabulary that goes with 
computer imaging: A photograph is taken - it is than digitized by scanning -
this is called 'image capturing,' the next step is 'image processing' here you
work upon the image within an application such as Photoshop. The final  step
is image storing, either by filing to disk or by sending the image to a 'list
device' (lst) - a printer.  Throughout any discussion of computer photography
the major focus is on the 'processing.' The original act of taking a
photograph is merely the procurement of an image to be processed.  This is a
far cry from Edward Weston's belief that you should 'pre-visualize' the final
print in the ground glass of your camera. Or from Cartier-Bresson, who
considered the act of seeing and of taking the photograph as the essential
element, the realization of geometry in emotion at an instant in time. The
final photograph was of lesser moment. For Cartier-Bresson, an intense
engagement with the world was more important than what might come from it. 
Our discussion brings up four variables which may be very briefly summarized
as follows: 
Photography 1. A photography in the strict sense where the integrity of the
index is left in tact. I would like to call it, "straight photography,"
however the stylistic contrast between straight and pictorial photography
leads to confusion. Obviously, much of pictorial photography is straight in
the way I would want to use the word. Let me settle for an inelegant
'unmanipulated' photography. 
Photography 2. A photography that obliterates, through manipulation, the
indexicality of the photograph. The manipulation destroys photography's
Commentator 1. Commentators on photography who are sensitive to it
indexicality. They focus on the photograph in relationship to the world
revealed by the photograph - the historical context, issues of ethics and
power in the relationship of the photograph to and photographed. One topic
that rubs up into my field of anthropology is the representation of the
"other," especially during colonial expansion. The art of the photograph is
not addressed. 
Commentator 2. Commentators on photography who see photography as an art form
and welcome the complex mixed media genres as harbinger of a regenerated
photography. The indexicality is belittled as a 'myth' or is simply ignored. 
What is interesting is when the two types of commentary cross paths as they
invariably do before a simple indexical photograph of a human subject. Let's
take a look at America's most celebrated person picture, Dorothea Lange's 
'Migrant Mother.' 
Commentator 1. will tell you immediately that we are talking about Florence
Thompson and her daughters Norma, Katherine & Rubby. What has become of them?
How did Lange approach the family when she came to take the picture? Where did
the photograph fit into the FSA project, what was the relationship of Lange to
the other photographers and they all to Roy Stryker and what was the
relationship of the FSA to ideology of the New Deal? How was the photograph
used then and how is it used now. And what prompted the creation of this
unique documentary archive and how did it end up in the library of Congress? 
If commentator 1. looks at the set of six photographs Lange took he/she notes
that in one Florence Thompson has the start of a smile and in two others 
there is a fourth child, an adolescent lounging in a rocker. The adolescent
has a far away look in her eyes. Is she dreaming about Clark Gable? By pulling
the one photograph out and forgetting the others can we infer that there is
some propaganda angle at play? These are just the beginning of the questions
to ask and explore! 
Commentator 2. may perhaps dismiss the photograph as a 'shop worn' cliche (as
one critic I read referred to Brassai's Paris at Night photographs). But if
pressed Commentator 2. will talk of the emotion in the face, the iconography
of the madonna, and strong formal arrangement with the mother's arm bringing
our eye to her face. The children are present but bury their faces against
their mother. We know they are there, but we are not distracted from the
mother. If commentator 2. exams the set of six he/she will see the 
progression of Lange's eye, step by step as she approaches her final pose -
the contact sheet as a page from a poetic sketch book, is the phrase. Beyond
the "migrant mother" photograph commentator 2. will want to place it in
Lange's other work at the time and compare it to what preceded the FSA time
and what came later. 
How can I end? Can I imagine that these two conflicting commentators exist
simultaneously in the spirit of an any active and accomplished photographer of
people? They must, and perhaps the presence of commentator 1. explains why
photographers like Dorothea Lange resisted calling themselves artists.   
I concluded my talk by showing two sets of photographs. The first set stemmed
from the latter part of the discussion and consisted of a sample of
photographs I took during my field work in Africa. I'll post a set of them on
the WWW within a month. Regardless of their intrinsic merit they represent a 
photographer's frame of mind. 
Secondly, going back to the opening question of photography and language and
the kinds of communication each represents I ran photographs against a text. 
Short excerpts from Lewis Carroll's Alice book were read while thrown up on
the screen were a set of Charles Dodgeson's child pictures. Do looking at the
pictures effect how we hear and understand the words was my query? Do they
make us think differently about Alice and her creator? Try it for yourself to
see. It is a lot of fun. 
"The question is," said Alice, "whether you -can- make words mean so many
different things." 
"The question is," said Humpty Dumpty, "which is to be master - that's all." 
   J. David Sapir                                       (804) 924-6821
   Department of Anthropology                        ds8s@virginia.edu
   University of Virginia         http://fermi.clas.virginia.edu/~ds8s 
   Charlottesville, VA 22903                          "Fixing Shadows"  
Note 29.9  -< Hundreds of Film/Developer Processing Instructions >-
Subject: FAQ: B&W Film/Developer combinations
From: revdoc@wumpus.cc.uow.edu.au (Phil Herring)
(Last update: December 1994; some times for Tri-X added; times for 
Ilford Delta films added. The list now contains 296 film/developer 
B&W Film + Developer Combinations -------------------------------
This list has been compiled from data sheets that I've accumulated  over the
years, and shows the recommended processing times for a wide  range of films
in a wide range of developers. For each, the recommended ASA  rating is
listed; some are intended for push-processing. The recommended  agitation
routine is also shown, along with an indication of the resulting  negative
contrast, and the source of the information.
Old and/or obsolete films have been included. Beware: some of  their
replacements have similar names but may have quite different  processing
Note that these times should be treated as starting points only.  Processing
variables will mean that you will never be able to replicate the  conditions
used by the manufacturers to produce their figures; besides, only  you can
decide how you want your negatives to look.
All times are for 20 degrees C; that's 68 degrees F for those of you  still
living in the dark ages. (Except for the time for Kodak TMZ from  Kodak; the
figures shown are for 21 degrees C/70 degrees F.) 35mm format in  a daylight
tank is assumed.
Disclaimer: I'm not responsible for any of this information. Errors  are
probably typos.
Thanks go to Andreas Wolpers (wolpers@dfki.uni-sb.de) for  supplying the
times for Ilford Delta films.
If your favourite film/developer combination isn't here, feel free to  mail
me the details for inclusion in future versions of this list. Be sure to
send times at 20 degrees C, and include the resulting film speed,  the
intended agititation pattern, resulting contrast (i.e. whether it's intended
for a condenser or diffusion enlarger) and the source of  your information.
For consistency, manufacturers' recommendations are preferable, but personal
processing times will be included when  nothing else is available.
Film                    Developer       ASA     Min     Agit    Cont    Source
----                    ---------       ---     ---     ----    ----    ------
Agfa Ortho 25           Neutol NE       25      3       NA      NA      4
                        Neutol          25      3
                        Rodinal 1:10    25      5
                        Refinal         25      10
Agfapan 25              Atomal          25      7       D       C       4
                        Refinal         25      4
                        Rodinal 1:25    25      4
                        Rodinal 1:50    25      6       E       C       5
                        Rodinal Special 25      2.5
                        Studional 1:25  25      2.5
Agfapan APX25           Atomal          25      17      D       D       4
                        Refinal         25      6
                        Rodinal 1:25    25      6
                        Rodinal 1:50    25      10
                        Rodinal Special 25      4
                        Studional 1:15  25      4
Agfapan 100             Atomal          100     7       D       C       4
                        Refinal         100     6
                        Rodinal 1:25    100     5
                        Rodinal Special 100     4.5
                        Rodinal 1:50    100     7.5     E       C       5
                        Studional 1:25  100     4.5
Agfapan APX100          Atomal          100     13      D       D       4
                        Refinal         100     6
                        Rodinal 1:25    100     8
                        Rodinal 1:50    100     17
                        Rodinal Special 100     4
                        Studional 1:15  100     4
Agfapan 400             Atomal          400     11      D       C       4
                                        1600    16
                        Refinal         400     6
                        Rodinal 1:25    400     7
                        Rodinal 1:50    400     11 
                        Rodinal Special 400     4.5     E       C       5
                        Studional 1:25  400     4.5
                        HC110 dil B     400     6       C               4

Fuji Neopan 400         Rodinal 1:25    400     6       D       D       4
                        Rodinal 1:50    400     11
Fuji Neopan 1600        Microfine       400     6       A       C       1
                        T-Max           3200    10
                                        1600    4.5
                        D-76            3200    15
                                        1600    7.5
                        D-76 1:1        1600    9
                                        800     7
                        Microdol-X      800     8.25
                                        400     6.5
                        HC-110 (Dil B)  1600    7 
                        Microphen       3200    5.75
                        ID-11           1600    6.5
                                        800     4.5
                        SPD             1600    4.25
                                        3200    8
                        SPD 1:1         800     4.5
                                        1600    6.5
                        Fujidol         1600    6.5
                        Rodinal 1:25    1600    5       D       D       4
                        Rodinal 1:50    1600    8
Ilford Pan F            Perceptol       25      11      B       C       2
                        Perceptol 1:1   32      12.5
                        Perceptol 1:3   32      17
                        ID-11           50      6
                        ID-11 1:1       50      8.5
                        ID-11 1:3       50      12.5
                        Microphen       64      4.5
                        Microphen 1:1   64      5.5
                        Microphen 1:3   64      8.5
                        Rodinal 1:25    32      5       D       D       4
                        Rodinal 1:50    32      15
Ilford FP4              Perceptol       64      10      B       C       2
                        Perceptol 1:1   100     11
                        Perceptol 1:3   100     16
                        ID-11           125     6.5
                        ID-11 1:1       125     9
                        ID-11 1:3       125     15
                        Microphen       200     5
                        Microphen 1:1   200     8
                        Microphen 1:3   200     11
                        Rodinal 1:25    125     9       D       D       4
                        Rodinal 1:50    125     18
Ilford FP4+             Plus 1:9        125     3       B       C       2
                                        200     4
                        Plus 1:19       50      4.5
                                        125     6
                                        200     8.5
                        Plus 1:29       50      6
                                        125     8
                                        200     12
                        Ilfosol S 1:9   50      3.5
                                        125     4
                                        200     5
                        ID-11           50      5
                                        125     6
                                        200     8
                        Microphen       125     5.6
                                        200     6.5
                        Perceptol       50      7.5
Ilford HP5              Perceptol       200     11      B       C       2
                        Perceptol 1:1   200     14
                        Perceptol 1:3   200     21
                        ID-11           400     7.5
                        ID-11 1:1       400     12
                        ID-11 1:3       400     21
                        Microphen       500     6
                        Microphen 1:1   500     11
                        Microphen 1:3   500     22
                        Rodinal 1:25    400     6       E       C       5
                        Rodinal 1:50    400     9
                        HC-11O "B"      800     8       C
                                        400     7       C

Ilford HP5+             Perceptol       400     11      B       C       2
                        Perceptol 1:1   400     15
                        Perceptol 1:3   400     25
                        ID-11           400     7.5
                                        800     10.5
                                        1600    14
                        ID-11 1:1       400     13
                                        800     16.5
                        ID-11 1:3       400     20
                        Microphen       500     6.5
                                        800     8
                                        1600    11
                                        3200    16
                        Microphen 1:1   400     12
                                        800     15
                        Microphen 1:3   400     23
                        Plus 1:9        400     3.5
                                        800     5
                                        1600    7.5
                                        3200    11
                        Plus 1:19       400     6.5
                                        800     9.5
                                        1600    14
                        Plus 1:29       400     9
                        Ilfotec HC 1:15 400     3.5
                                        800     5
                                        1600    7.5
                                        3200    11
                        Ilfotec HC 1:31 400     6.5
                                        800     9.5
                                        1600    14
                        I'tec LC29 1:9  400     3.5
                                        800     5
                                        1600    7.5
                                        3200    11
                        I'tec LC29 1:19 400     6.5
                                        800     9.5
                                        1600    14
                        I'tec LC29 1:29 400     9
                        Ilfosol S 1:9   400     7
                                        800     8.5
                                        1600    14
                        Ilfosol S 1:14  400     9.5
                                        800     14
                        D-76            400     7.5
                                        800     9.5
                                        1600    12.5
                        T-Max 1:4       400     6.5
                                        800     8
                                        1600    9.5
                                        3200    11.5
                        Acufine         400     4.5
                                        800     6.5
                                        1600    9.5
                        Rodinal 1:25    400     6
                                        800     8
                        Rodinal 1:25    400     8       D       D       4

Ilford Delta 100        ID-11           50      6       B       C       2
                                        100     7
                                        200     11
                        Microphen       100     8
                                        200     12
                        Perceptol       50      10
                                        100     15
                        I'tec HC 1:31   50      4.5
                                        100     5.5
                        I'tec LC29 1:19 50      4.5
                                        100     5.5
                        Ilfosol 1:9     50      3.5
                                        100     5
                        D-76            50      6
                                        100     7
                                        200     11
                        T-Max 1:4       100     6
                                        200     8
                        Acufine         100     3.5
                                        200     5
                        Rodinal 1:25    50      4 **NR poss uneven development
                                        100     7
                                        200     NR

Ilford Delta 400        ID-11           200     5.5     B       C       2
                                        400     7
                                        800     9.5
                        Microphen       400     5.5
                                        800     8
                        Perceptol       200     10.5
                                        400     13
                        I'tec HC 1:31   200     6
                                        400     7
                                        800     9.5
                        I'tec LC29 1:19 200     6
                                        400     7
                                        800     9.5
                        Ilfosol 1:9     200     4.5
                                        400     7
                                        800     10.5
                        D-76            200     5.5
                                        400     7
                                        800     9.5
                        T-Max 1:4       400     5.5
                                        400     7
                                        800     9
                        Acufine         400     4.5
                                        800     6
                        Rodinal 1:25    200     6
                                        400     7
                                        800     10.5
                        Rodinal 1:50    200     12
                                        400     16.5
                                        800     NR
                                       1600     NR
Kodak Tech Pan          Technidol LC    16-25   5-11    F       C-D     3
                        Dektol          200     3               H1       
                        D-19            100-200 2-8             H2
                        D-19 1:2        100-160 4-7             H3
                        HC-110 (Dil B)  100-250 4-12            H4
                        D-76            64-125  6-12            H5
                        HC-110 (Dil F)  32-64   6-12            H6
Kodak Panatomic-X       Perceptol       25      7       B       C       2
                        Perceptol 1:1   32      8.5
                        Perceptol 1:3   32      9
                        D-76            32      5
                        Microdol-X      32      7
                        HC-110 Dil. B   32      4.25
                        ID-11           32      5
                        ID-11 1:1       32      7
                        ID-11 1:3       32      12
                        Microphen       64      5.5
                        Microphen 1:1   64      7.5
                        Microphen 1:3   64      13.5
                        Rodinal 1:25    32      5       D       D       4
                        Rodinal 1:50    32      11
Kodak Plus-X pan        Perceptol       64      8       B       C       2
                        Perceptol 1:1   64      8.5
                        Perceptol 1:3   64      12
                        ID-11           125     6
                        ID-11 1:1       125     8
                        ID-11 1:3       125     13
                        Microphen       200     6
                        Microphen 1:1   200     8.5
                        Microphen 1:3   200     13.5
                        Rodinal 1:25    125     6       D       D       4
                        Rodinal 1:50    125     13
Kodak Tri-X pan         Perceptol       320     10      B       C       2
                        Perceptol 1:1   320     12
                        Perceptol 1:3   320     15
                        ID-11           400     8
                        ID-11 1:1       400     11
                        ID-11 1:3       400     9
                        Microphen       500     6
                        Microphen 1:1   500     11
                        Microphen 1:3   500     22
                        T-Max           400     6       C       C       3  
                        T-Max RS        400     6
                        HC-110 (Dil B)  400     7.5
                        D-76            400     8
                        D-76 1:1        400     10
                        Microdol        400     10
                        Rodinal 1:25    400     7       D       D       4
                        Rodinal 1:50    400     16
Kodak HS IR             D-76            NA      11      C       NA      3
                        HC-110 (Dil B)  NA      6
                        D-19            NA      6
Kodak TMX               T-Max           100     8       C       C       3  
                        D-76            100     9
                        D-76 1:1        100     12
                        HC-110 (Dil B)  100     7
                        Microdol-X      100     13.5
                        Rodinal 1:25    100     5.5     D       D       4
                        Rodinal 1:50    100     12
Kodak TMY               T-Max           400     7       C       C       3  
                        D-76            400     8
                        D-76 1:1        400     12.5
                        HC-110 (Dil B)  400     6
                        Microdol-X      400     10.5
                        Rodinal 1:25    400     5       D       D       4
                        Rodinal 1:50    400     10
Kodak TMZ               T-Max           800     7.5     C       C       3
                                        1600    8.0
                                        3200    11
                                        6400    13
                                        12500   15.5
                        D-76            1600    10.5
                                        3200    13.5
                                        6400    16
                        HC-110 (Dil B)  1600    7.5
                                        3200    10
                                        6400    12
                        Rodinal 1:25    3200    8       D       D       4
                        Rodinal 1:50    3200    16
Kodak Recording 2475    Rodinal 1:25    ?       4.5     D       D       
                        Rodinal 1:50    ?       10
Konica IR 750           Konicadol DP    32      6       A       C       6
                        D-76            32      6
                        Konicadol Fine  32      7
                        DK-20           32      7
                        Konicadol Super 32      6
                        ID-66           32      6
        A       Cont. for first minute, then five seconds each minute
        B       Cont. for first 10 seconds, then ten seconds each minute
        C       Cont. for 60 seconds, then five seconds every 30 secs.
        D       Cont. for first minute, then every 30 secsonds
        E       Cont. for 30 seconds, then five seconds every 30 seconds
        F       Shake tank 10 times rapidly for 2 seconds every 30 seconds.
        C       Condenser enlarger
        D       Diffusion enlarger
        H1      CI = 2.50
        H2      CI = 2.25-2.55
        H3      CI = 2.40-2.70
        H4      CI = 1.20-2.10
        H5      CI = 1.10-2.10
        H6      CI = 0.80-0.95
Official Sources
        1 Fuji Photo Film Co., Ltd.
        2 Ilford Limited
        3 Eastman Kodak Company
        4 Agfa-Gavaert
        6 Konica Corporation
Other Sources
        5 Jens Madsen (local pro photo shop)
(c) 1994 Rev. Dr. Phil Herring                revdoc@wumpus.cc.uow.edu.au
       - Church of the Sacred Dial Tone, Wollongong, Australia -
Unauthorised reproduction of this article for profit will result in civil 
action. All other distribution is encouraged.
===========================  end of section 29 ========================== 
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