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    FAQ or Answers to Frequently Asked Questions                  Section 44
                Please check "root" 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. 
                    These files are available in SECTIONS. 
             This is Section 44 and its contents are listed below.
    44.01  -< Color Correction Conundrum >-
    44.02  -< Removing Dye Layers from Color Film One at a Time >-
    44.03  -< What is the actual f stop given by lightmeters? >-
    44.04  -< The Arnold Gassan Method for HC-110 >-
    44.05  -< Photos of your "aura" ... Kirlian Photography >-
    44.06  -< How to expose Night Scenes properly, a guide >-
    44.07  -< Removing Scratches from lenses ... regrinding surface? >-
    44.08  -< Shooting digital or scanning film, which is better? >-
    44.09  -< Split Toning advice >-
    44.10  -< Photographing (shooting) with a steady hand, how? >-

44.01               -< Color Correction Conundrum >-
> In the case of shooting daylight film in incandescent conditions, is the
> problem only in the highlights of the blue channel (trannies), if so can we
> put the detail back if we had bracketed the shot at 3 half stops?-1/2 0 1/2?
Well, with trani, the question is probably moot, as the colour cast would be
rather objectionable.  That is, unless one is going to print from the trani,
and thus has the benefit of being able to attempt to correct for the cast.
I'm really going to have to draw some pictures to illustrate my point here.
Lets assume the film has the following curves when exposed and processed
normally (correct CT light source etc...
e                   .-------
n                .' 
s               . 
i              .
t             .
y            .
|           .
|         .'
You'll notice that this is a negative material, but that doesn't really matter.
I've only drawn a single curve because this theoretical film has R, G, and B
emulsions that have exactly the same curve.  (Naturally they don't in practice,
but over the normally used part of the curve, they're pretty close)
Now, if we use a light source that has a lower colour temperature, the curve
would look like this (and this is going to be hard to draw, so I'll only
attempt to draw the Red and blue curve (the green would fall somewhere in
e                   .----.-----
n                .'   .'
s               .   .
i              .   .
t             .   .
y            .   .
|           .   .
|         .'  .'
In this case (with LOW CT light source) the line to the RIGHT is the BLUE
density, the one to the LEFT is the RED density.
Since the CT is low, a given exposure (duration) causes less exposure (and thus
density) in the blue as compares with the red.  Or, conversely, a longer
exposure is required to achieve the same BLUE density as compared with RED
(OK, the dyes are really cyan and yellow, so when I say RED density I am
referring to the density of the red-sensitive (cyan) layer)
Let's look at some points on here these more closely.

e                   .----.-----
n                .'   .'
s               e   .
i              .   .
t             .   .
y            d   .
|           .   e
|         c'  .'
at point (a) neither emulsion layer has received enough exposure to generate a
density greater than b+f 
at point (b) the RED density is (say) at it's speed point and we start to get
printable detail here.  However the BLUE density is still at b+f
at point (c) the Red curve is well into the toe region, but the BLUE density
has yet to reach the speed point.  Note that the difference in density is 1
unit (whatever these units are)
at point (d) the blue curve has finally reached the speed point, so there is
some printable detail in the Blue, but the RED curve is well into the (more)
linear part of the curve.  Note that the difference in density is 3 units.
at point (e) both curves are into their linear region and the difference in
density is 4 units.
assuming the "linear" portion of the curve is actually linear, the difference
will remain at 4 units until the RED curve hits the start of the shoulder
region.  At that point the difference will slowly diminish until both densities
are again the same well into the shoulder region of the BLUE layer.
So what does this mean for filtration when printing?  Well, in the middle area
(where the difference between the curves remains at 4 units, a filter that has
a density of 4 units of blue (-4 yellow) will put the curves together again,
but in the areas near the toe and shoulder (where the difference in density is
less than 4 units) a colour cast will appear.
This cast will be yellow in both the shadow and highlight regions.  This is not
correctable with filters (of the conventional type) because they can't tell
what part of the curve a particular piece of film is (and hence are not able to
change their density accordingly - THAT would be magic!).  However it is not
outside the bounds of possibility that a software filter could alter the effect
of the filtration depending on density in order to remove the cast -- note
however that to be perfect a model of the actual characteristics of that film
would have to be known by the software filter.
But there's more!  (steak knives?)
Even once we've removed the colour cast problem the fact remains that there is
detail in the RED layer in deeper shadows than in the BLUE layer.  Thus a line
of red and blue balls under graduated lighting would see the blue balls seem to
get darker and disappear into the gloom well before the red balls.  In terms of
texture, this would tend to show texture in shadow in reds, rather than grays.
But there's even more!
The above assumed that the linear portion of a film's density curve is actually
linear.  Well, it's not.  And the more it deviates from linear (except for some
strange shapes based on inverse natural logs) the worse the problems will be,
since it may not be possible to correct more than a small range of densities
The less the difference between the CT of the light source and the CT the film
is designed for, the less this effect.  So, the closer to full correction you
can get, the better.  As you get close, the effects of the mismatch become
insignificant and easily corrected in printing.
The longer the "straight line" portion of the curve, and sufficient exposure to
ensure that the LEAST exposed layer of emulsion records shadow detail that you
want to print, go a long way to making acceptable images (as does the
combination of relatively low contrast film and higher contrast paper).
My 2c worth :-)  (I wonder if they're Euro-cents, if so, you'll have to wait 2
years, or accept a cheque)
Steve Hodges 

44.02        -< Removing Dye Layers from Color Film One at a Time >-
> Is it possible to remove specific dye layer densities from color transparency
> materials without affecting the others? How about removing all three
> simultaneously?

These are the formulae for selective bleaches for Kodak dyes as shown in the
1975 Almanac of the British Journal of Photography..... Ektacolor materials 
.... with testing, others mfgrs and sys will likely work.
   Cyan Dye Bleach SR14
        water............................ 800 ml
        sodium hypochlorite (5%)........   10 ml
        water to 1 litre

   domestic bleach is the cheapest and most convenient source


   Magenta Dye Bleach SR15
        water............................... 200 ml
        perchloric acid (20%)..............  500 ml
        water to 1 litre
   CAUTION: do not mix in a metal container.  Avoid contact with combustible 
   material and if spilled, flush with LARGE quantities of water.


   Yellow Dye Bleach SR17
        water.................................  800 ml
        sulphuric acid (conc.)................  120 ml
        water to 1 litre
   CAUTION: add acid to water, slowly.... will put hole in clothing unless
   washed immediately with an alkaline bath.


   Non Selective Dye Bleach    R19
   Stock Solution A:
                  Water @ 120F............................. 800 ml
                  potassium permanganate...................  60 gm
                  water to 1 litre
   Stock Solution B
                  water...................................  800 ml
                  sulphuric acid (conc.)..................  100 ml
                  water to 1 litre
                  WORKING SOLUTION:        
Mix 5 parts of stock A with 1 part of stock B only immediately before using. 
It is sensible to make 5 times as much of stock A as of B ..... do not use a
metal cap for stock A or B.

                  water..................................   800 ml
                  sodium bisuphite......................     50 gm
                  water to 1 litre
"Metabisulphite" is easier to obtain generally , and can replace bisulphite 

These formulae are apparently sourced from Kodak.... so there must be so me
E.K.   pamphlets/books/etc available from them for further explanations and p
erhaps updates to contemporary dye chemistries...... SOMEBODY in Rochester will
know !!!
FROM: ----------------------fwmscanlonryersonpolytechnicaluniversity

44.03  -<  What is the actual f stop when f stops are given by lightmeters? >-
> Most digital hand held exposure meters give F-stop readings to one
> tenth of a stop.  How can I determine what the actual f-stop is?  For
> example, if the meter reads f2.8 + 4/10ths, is the f-stop f3.2?  Any
> formulas and/or tables would be appreciated.
Hmmmm .... interesting question. Let's see ... I would approach this from the
belief that a 1 stop change is equal to a log exposure change of .3 so a 1/10
stop change is equal to a log exposure change of .03
Now how to translate this into actual apertures ... let's see ...
Suppose I started with f/4 ... let's set up a "table" based on the fact that 1
stop less than f/4 is 5.6 and 1 stop more is f/2.8 and then knowing that a 1
stop change is .3 and 1/10 is .03 then something like this "appears" ....
                aperture  aperture  log 
                          squared   aperture 
-1 stop   (known)   5.6     32      1.5     \
-9/10                               1.37     |
-8/10                               1.44     |
-7/10                               1.41     |
-6/10                               1.38     |
-1/2                4.73            1.35      > difference is .3 (one stop)
-4/10                               1.32     |
-3/10                               1.29     |
-2/10                               1.26     |
-1/10                               1.23     |
4  starting         4       16      1.20    /  \
+1/10                               1.17        |
+2/10                               1.14        |
+3/10                               1.11        |
+4/10                               1.08        |
+1/2                3.35            1.05         > also a log diff of .3
+6/10                               1.02        |
+7/10                                .99        |
+8/10                                .96        |
+9/10                                .93        |
+1 stop   (known)   2.8      8       .90       /
From this I figure that I can square any aperture and find it's log, 
then subtract or add whatever number of tenths of a stop change I will 
make multiplied by .03, then find the antilog of this new number and 
find its square root and that is the new aperture.
I hope this helps some ...
Andy  o o  0 0 o . o  Andrew Davidhazy, Imaging and Photo Tech
       \/\/\/\/\/\/   http://www.rit.edu/~andpph  716-475-2592  
________|        |____________________________________________

First, lets start with the formula used to determine f-stop.
f-number = [focal length of lens] / [diameter of aperture]
The intensity of the light is controlled by the area of the aperture.
Therefore, as you increase the f-number by some factor, you increase the
intensity of the light by the square of that factor.  For instance, increasing
from f/2 to f/4 will double the f-stop and increase the intensity of the light
by four.  Check this with a calculator.
Next, look at the standard series of f-stops.
0.7, 1.0, 1.4, 2.0, 2.8, 4.0, 5.6, 8.0, 11.0, 16.0, 22.0, 32.0, etc...
Using your calculator and the formula from above, you will see that the
intensity of the light passing through the aperture increases by nearly two
times as you move through the series from 0.7 to 32.0.  This is why opening up
one stop will require half the time to get an equivalent exposure.  This series
is the same series that your light meter will read out.
Looking at the spacing between numbers, it should be apparent that the
increments are not equal nor are they evenly divided into tenths.  Therefore, a
reading of f/2.8 and four tenths is not equivalent to f/3.2.
The difference between f/2.8 and f/4.0 is 1.20.  Dividing 1.20 by 10 yields
0.12.  This number should be [in your example] multiplied by four to obtain a
product of 0.48, add this number to 2.8 to get a final f-stop of f/3.28 which is
close to f/3.2, but not quite.  A more dramatic example would be a reading of
f/11 and four-tenths which translates to f/13, not f/11.4 as suggested by the
meter reading.
To calculate the change in intensity in the above example, divide 3.28 by 2.8 to
get a factor of 1.17.  Since the aperture is being reduced, the intensity of the
light is also being reduced.  Therefore, the inverse of the factor squared will
tell you the change of intensity.
In this example:
Tenth of Change Between f/2.8 and f/4.0 = [f/4.0 - f/2.8] / 10 = 1.20 / 10 =
New f-number = [4 * 0.12] + f/2.8 = 0.48 + f/2.8 = f/3.28
f-number Factor = [f/3.28] / [f/2.0] = 1.17
Intensity Change = 1 / [f-number factor squared] = 1 / [1.17 * 1.17] = 1 / 1.37
= 0.73
Intensity Change = [0.73 * 100] - 1.0 = -27%
Since your intensity was reduced by 27%, the exposure time would have to be
increased by 27% as well.
The important thing to remember is that when you are changing the f-stop, you
are really changing the intensity of the light hitting the film.  You do this by
changing the area of the aperture, in relation to the focal length of the lens.
The following resources may be helpful.
Seeing the Light: Optics in Nature, Photography, Color, Vision, and Holography;
by David Falk, Dieter Brill, and David Stork.
Basic Photography: Materials and Processes; by Leslie Stroebel, John Compton,
Ira Current, and Richard Zakia.
Kodak's Encyclopedia of Practical Photography.

Brady Hackleman 


I did entertain the idea of 1/10th stop divisions calculated as ten equal
devisions of a full stop increase or decrease. Deductive reasoning leads me to
beleive that the divisions must be logarithmic.

Consider the following: Your spot meter indicates an exposure of some shutter
speed at f/11 and 5/10ths. You set your aperture ring, that we will asum e is
calibrated accurately, to the ratcheted stop between f/11 and f/16. If the stop
meter indicated an arithmetic division of stops, your exposure would be wrong.
To use a long shutter speed for the sake of illustration; let's say that a 10
second shutter speed was necesary [our film does not experience reciprocity
failure either] for an exposure at f/11. Logarithmic calculation yeilds a
shutter speed of 14.14seconds at f/11 and 5/10ths. If your spotmeter was
indicating tenth-stop incremets arithmetically derived, it thinks you are
making an exposure for 15.00 seconds; and so you have just underexposed by 0.86
14.14 second calculation: logarithmic arguement
[10 seconds at f/11] X [2^(0.5 stop increase in time)]
10 X 1.141
14.14 seconds
15 second calculation: arithmetic scale
[10 seconds at f/11] + 5[((2^1 x 10 seconds) - 10 seconds) / 10]
[10] + 5[(20 seconds for f/22 - 10 seconds for f/11) / 10 for tenths of a stop]
[10] + 5[(10 second range of a full stop increase in exposure) / 10]
[10] + 5[ 10 / 10 ]
10 + 5
15.00 seconds
Typically we regulate exposure in 1/2 or 1/3 stop increments; knowing this the
manufactures of the stop meter must set their tenth of a stop scale to be
logarithmic, or the exposures indicated by thier meter would be inconsistent
with the exposure settings the common photographer makes.
From: Keith Hanson KWH4490@ritvax.isc.rit.edu
44.04         -< The Arnold Gassan Method for HC-110 >-
Here it is the Arnold Gassen Method for HC-110.  From the still living 
Arnold Gassen long may he wave.
HC-110 Make a working stock of 1 part HC-110 to 9 parts water. Dilute the
working stock as follows to get 900 ml of developing  solution
Dilution                        1:9 stock               water
1:30                            300ml                   600ml
1:40                            224ml                   676ml
1:50                            180ml                   720ml
1:60                            150ml                   750ml
1:65                            138ml                   762ml
1:70                            124ml                   776ml
1:80                            100ml                   800ml
Time for normal emulsion films(Tri-X, Plus-X, HP5, FP4, Pan-F)
Time for T-Grain type films (T-MAX 100 and 400, any similar technology euro
films) ALWAYS 6.5 MINS AT 70 DEGREES (ps: this is an addition to AG's original
method, which was  formulated before such films were made the time was
formulated by Tillman Crane through testing and densitometer reading and is
*Time for Kodak HIE film 5 mins (ps: this suggested by Sharon Fox originally
and I think only anecdotally tested, certainly anecdotally only by me, do your
own tests guys)
Now use the following dilutions to deveop your film according to the desired 
Film            Development desired
                N--     N-      N       N+      N++
Tri-X           1:60    1:50    1:40    1:30    ----
Plus-X          -----   1:80    1:70    1:60    1:50
Pan-X           -----   1:80    1:70    1:60    1:50
HP5             1:70    1:65    1:60    1:55    -----
FP4             1:70    1:65    1:60    1:55    -----   
Pan-F           1:80    1:70    1:60    1:50    ----
T-max 100       test    1:50    1:40    1:30    test
T-max 400       test    1:50    1:40    1:30    test
HIE             test    test    1:20    test    test
T-max 3200 Not recommended for this method
Sorry about only the suggested start point for HIE. Test, test test. And the
same rules that always apply, apply here, development effects the highlights,
exposure--shadows. Expose for shadows and use this the appropriate dilution to
cut down or increase highlights. ( Don't everyone write me posts saying DUH!)

From: "Amber" 
44.05        -< Photos of your "aura" ... Kirlian Photography >-
> I remember seeing, some time ago, some photos which showed electrical 
> charges emanating from objects, such as hands, leaves, etc.  The name was
> something like kerilian  photography, but I know that this isn't what
> it is called, because I can't find anything on that subject anyplace. 
> Can anyone tell me what it is called, and what the process involves, and
> perhaps recommend some good resources to learn how to do it.

I remember doing a little research years ago. It is either Karelian,  Kralian,
Kerilian, Krelian or a variation. Sorry I don't have the name  handy anymore.
"Krelian" comes closest to my memory. Anyway, it involves  creating a sandwich
of 2 electrically conducting plates around a test  object and a sheet of film
and attaching a high voltage (I think high  frequency [more or less square wave
DC voltage]) to the plates.
Unsurprisingly, an electric discharge occurs, exposing the film - which is 
then developed. Pretty straight forward so far.
The hocus-pocus follows with interpreting the results. For no good reason, 
many assume that these images represent some unknown energy field, such as  the
"Aura" assumed (with no real evidence) to exist around living things.  My (not
thorough) investigation found no evidence that the pictures were  anything but
the expected exposures caused by the applied high voltage  discharges
For example:

1) Metal objects (usually coins are used) have a field (coins are alive?)
2) Some living samples show no field (seems to depend on water content of 
3) The fact that the fields vary in color, shape and intensity are used to 
   diagnose disease, etc. It's the old story of setting up a very random or 
   noisy system and then putting your interpretation on the results (as in 
   inkblots, faces on Mars, the Virgin Mary in cracks in a ceiling or clouds, 
   etc., etc.). Naturally these discharges are sensitive to many disturbances, 
   such as plate spacing, irregularities in the surfaces, impurities on the 
   plates and subject surfaces, humidity and temperature effects and on and 
   on. There is no reason to assume that the variations mean anything else.
The strongest evidence for the "Aura", "Bio-Energy", etc. claim was a set  of
two photos of a plant leaf. In one, the leaf is whole and shows a  discharge
all around the edges. In the other, the end of the leaf has been  removed, but
the discharge still shows the original shape - including the  missing piece.
This was claimed to be a photo of the "ghost" of the missing  piece of leaf, or
its "bio-memory" or "invisible natural field" or some  such. This seemed to be
the only unusual result of this whole high voltage  photography effort. I don't
remember the details, but several people tried  to repeat this experiment and
never got any "ghost effect". I think the  probability is very high that it was
a fake. This pair of photos was widely  publicized in color and B&W. It was
called the "Missing Leaf Phenomena", If  memory serves.
A few years ago I attended a "Holistic Health Fair" were a lot of snake oil 
was sold. One man had a Krelian type high voltage apparatus (which he  claimed
to have invented himself) and was strapping it on peoples hands. He  made
Polaroid's of their discharges and was making a lot of medical  diagnostic
claims about the results. There was a long line at his booth. I  think he was
getting $20 - $30 a shot. {Booth photographers take note :-) }  Since most of
the booths were the usual Tarot readers and Astrologers this  man's
pseudo-scientific technical show really stood out. Sparks and  everything!
Shades of Frankenstein!
I bought a paperback book on the subject called "The Krelian Aura". The 
"missing leaf" was on the cover. I think it is extremely interesting to
experiment with the various "fringe science" effects. There are a lot of
resources on the Web. I hope you give it a try and report back to the group.
Maybe you can duplicate the "missing leaf"!
Committee For The Scientific Investigation Of Claims Of The Paranormal 
(CISCOP) http://www.ciscop.org
Don Lancaster http://www.tinaja.com
Bill Beatty http://www.eskimo.com/~billb
The last 3 are sites with stuff on electronics and electronics  paused-science,
but lots of other stuff. I don't know if they have Krelian  stuff. These will
lead to a ton more.
Note: Just saw Andy's message as I was sending this - I think he has the 
correct spelling. He's right about high voltage being dangerous (ever get bit
by an auto  sparkplug?). You have to use high frequencies, voltages no higher
than necessary and VERY LOW CURRENTS (with protection circuits).
From: Jim Coe 

> Could this be done using a low-power Van de Graaf generator?  I remember a 
> college level physics class where a prof put his hand on one of these 
> machines, and then had his hair stand up on end. 
> I have asked this myself but never took the time to actually try it. I think
> you can also use an electrostatic vacuum leak detector. Having your hair stand
> on end is one thing. Creating a corona discharge off your body parts may be
> something a little different but then, maybe not. I would like to know as well
No, Kirlian photography does not make use of static discharges.  Rather it
makes use of high frequency corona discharge.  These signals are typically
generated using a Tesla coil.  The "skin effect" exhibited by high frequency
signals keeps the current flow from penetrating into a conductor or in this
case the subject's body.  This keeps things reasonably safe, although I would
suspect that one could get an rf burn if not careful. Just remember that rf
signals follow the path of least Impedance NOT the path of least resistance as
DC (Direct Current) does.
I did a quick search on Yahoo using the keyword kirlian and got several hits. 
One that looked sort of OK was:
I was also able to locate several pieces of information on this process in the
library several years ago.
As was pointed out by someone else, there is a lot of speculation about what
images made by this technique mean.  That is a topic in itself.
From: Wayde Allen 

44.06         -< How to expose Night Scenes properly, a guide >-
> I am hoping someone can give me some advice on how to take Night scene such 
> as buildings and city lights at night. How do you work out expoure times etc.
Although nothing is certain when you make broad generalizations, I have these
exposures for you to use as a guide when shooting the city lights at night. You
will be in the ballpark with these. They are all based on the sunny 16 rule
which states that a normal daylight exposure is always f16 at 1/iso. These
exposures are allowing more light in from the sunny 16 base exposure for your
Brightly lit buildings, such as a theatre district at night     6 stops more
Store windows at night                                          6 stops more
Brightly lit downtown street scenes at night                    7 stops more
Flood lit buildings, fountains, monuments at night             11 stops more
Distant view of the city skyline at night                      13 stops more
From: David Litschel, Chair, Faculty Board/CAO
Brooks Institute of Photography, 
Santa Barbara, California, USA, 93108
litsch@rain.org (David Litschel)

44.07    -< Removing Scratches from lenses ... regrinding surface? >-
> Do you know of anybody who regrinds lenses? I have one that exhibits fairly
> deep surface scratches.

One option is to call 
Longman Optical
c/- Technopark Centre
Dowsing Point
Tasmania  7010
You need to speak to Ian Mansfield on +61 3 6233 5505
This company can regrind lenses.  If the lens is not too deeply scratched they
can polish the scratch out and re-coat the lens.  For seep scratches, they may
not be able to completely polish them out.
I'm not associated with these people, and I have not yet used them.  I have had
second-hand reports that they do a very good job.
From: Steve Hodges
44.08     -< Shooting digital or scanning film, which is better? >-
> I need help with cameras, for instance, is it better to shoot the photos
> digitally (with a digital camera) or on film and scan the negative (I expect
> they'll be mostly print) with a good scanner? Should I invest in a CD 
> recorder for storage? If so, which would be most convenient and useful? 
> I know I'll need a new computer and am most familiar which a PC, with no 
> knowledge of the Mac. I have heard the Mac is better for graphics. Is this
> still true? Does the Mac offer any benefits over the PC platform? Will I be
> able to use my current peripheral equipment?  I'd like to print the scanned 
> images as photo quality if possible. I don't think my Epson Stylus Color 400 
> is up to that. Any suggestions?  
It depends on what you shoot, but unless you're willing to shoot mostly still
lifes and invest in a Very Expensive Indeed digital back for a medium format or
large format camera, it's better to shoot on film and scan it.
If you have 8x10" or even larger prints, you might get by with scanning them in
your HP printer, but to be honest, I'd say "don't". Get a good film scanner
instead. I assume that you shoot 35 mm. In that case, get the "best" (read:
most expensive) of the Polaroid 35 mm film scanners. Or start with having a
professional lab scan them onto Pro PhotoCD (Pro PhotoCD is always better than
"regular" PhotoCD, and you might opt not to have your neg or slide scanned at
the highest resolution -- Level 6 -- in order to save both money and space on
the disk. A Level 6 images is 72 MB in size while a Level 5 image is "only" 18
For storage, CD is probably the best. For submission, Syquest still rules, with
Zip quickly becoming the norm. If you can afford it, get a recorder that can
write at 4x speed, otherwise you'll end up spending much of your time waiting.
Yamaha makes good 4x recorders but there are also others. I've heard people
having problems with Pinnacle, but haven't tried it myself.
For the computer, choosing between Mac and PC is mostly a matter of preference
nowadays. But it might not always be easy to find a PC that's up to the task.
Let's assume that a typical image that you'll work with is 15-20 MB in size.
That's sufficient for printing at 8x10" size in a magazine. Expect Photoshop to
use between 3 and 5 times as much memory, plus another 16 MB. Between 128 and
192 MB of memory is enough. You can use less (64 MB for example, but it will be
much slower.
You can usually use your current peripherals such as disks on a Mac if they're
SCSI-based. Typically they're not. You can also use printers and the like if
they have an Appletalk connector. You can usually also use your current monitor
if you get a Macintosh adaptor.
A good Mac system for photographic use is the Powermac 7600/200 or the
Due to the diversity among the PCs, it's hard to recommend a specific system
(I've actually ended up building my own system), but things to watch out for
- The number of memory slots in a PC is limited. Make sure that only 32 MB or
larger EDO SIMM's are used. SDRAM is also great, but doesn't always work
perfectly. It's also more expensive. If possible, get a system with more than
the standard 4 SIMM slots.
- Get a system based on Pentium Pro or, if you think it's worth the money for a
minimal increase in performance, Pentium II. If you do get a standard Pentium
system, make sure that it contains a 200 MMX CPU since Photoshop 4 is
significantly faster with it than with a non-MMX CPU, and that the board has a
"HX" or "TX" chipset. The others can't handle more than 64 MB of memory well.
- SCSI peripherals generally work better than their IDE counterparts, but costs
twice as much. Stay away from SCSI-1. Make sure that you get at least SCSI-II,
preferably with "Ultra" transfer rate. Unfortunately, most Mac's can only use
SCSI-1 without extra accessories.
- Get a GOOD graphics card. You need at least 4 MB of video memory, preferably
8 MB if you plan to use a large monitor. I use a Matrox Millennium card, but
all the cards from Matrox are great performers.
- Get a GOOD monitor. My personal choice is Eizo. Also for the Mac.
- Get a Wacom graphics tablet, regardless of whether you choose a Mac or a PC.
Editing is so much easier with one. Most PC resellers won't know what this is,
though, but many Mac resellers will.
For printers, I recently bought an Epson Stylus Color 800. It's good but not
perfect, provided that you use the special coated glossy paper for photographic
Another thing -- get a CD recorder. It's the best way to store large graphic
files. I also use it for submissions since it's so universally accepted.
From: Robert Claeson 

44.09                   -< Split Toning advice >-
> One process I have always wanted to bring to the class has to do with split
> toning in selenium. I have seen photos resulting from this process but have 
> had some difficulty finding information on how it is done. I believe it is
> partially due to the emulsion. That some warm tone papers are more responsive
> and as well that the ph of the fix plays a part as well.

Selenium toning is not very complicated, and it replaces silver with
selenium, making prints super archival. It's important to agitate the
selenium so that it tones the prints evenly. The higher the concentration
the faster the results. A split tone on cold paper is pretty subtle,
whereas a warm paper such as Agfa will produce more obvious effects,
showing the split tone. Blacks are effected first, turning purplish, and
the way to acheive the split tone is by not allowing the lighter mid tones
to 'turn.'

From: SIBYL 


The most responsive modern (if you can call it that) paper is from Forte --
their Polywarmtone is terrific for split toning. Fixing has nothing to do with
it, at least not so far as I know,
From: Jan Faul 


I split tone my prints on Agfa Classic Fibre-based paper. I use Ilford MG
developer 1:9, and then tone the prints in selenium diluted 1:4 (after
correct fixing and hypo-clearing). The toning results in much richer blacks
(you can print your black as a dark dark grey, and then tone it to black)
and very warm reddish mid tones, but leaves the highlights neuteral. It is
quite stunning on the appropriate images (I predominantly use it on nudes).
Eric Boutilier-Brown, Fine Art Photographer, Nova Scotia, Canada


Successful split toning IMHO has many variables, one of the least predictable
is tonality of the image. In my experience warm tone papers are a must, but the
right kind of developer is another major plus.  I also tend to decrease my
development time from 2 mins to  1/12 mins to produce a "better" toned print,
this applies to any toning I plan to undertake post printing. The developer I
have used with some success to split tone is as follows,

Water 750 cc's @ 50 degrees Celsius
Metol 8 gms
Sodium Sulphite 23 gms
Sodium Carbonate 40 gms
Benzatriazole 50 cc's of 1% Solution
Water to 1 litre

I then tone in selenium 1:3, by inspection.
From: Stuart Murdoch 

44.10          -< Photographing (shooting) with a steady hand, how? >-
> Apart from bean bags, tripods and the odd wall has anyone any hints as
> to how to keep an arm steady for a hand held shot?

Steady hand (actually whole body should be steady) method for 35mm cameras:

1. Hang the camera around your neck. Have it in front of you resting against
your chest.

2. Hold the camera with you right hand using the normal grip.

3. With your left hand grasp the camera strap where it rests against the back
of you neck. You will be able to gauge exactly where to grasp the strap after
you have tried this a few times.

4. Pull down towards your feet with your left hand still grasping the strap.
This will cause the camera (and your right hand) to come up  so the camera is
against your face with your eye to the viewfinder.

5. With the left hand, without letting go of the strap, grasp the left side of 
the camera in more or less the normal left hand grip. If you have grabbed the
strap in the correct position the camera should be clamped tightly to your
face. If is not, try again, grabbing the strap in a slightly different position
so that the strap is holding the camera tightly to your face.

6. Stand with one foot forward and one back (as you would if firing a rifle).

7. Hold your breath, stand perfectly still and rigid and gently and slowly
squeeze the shutter release. Your finger should be the only part of you that

This  works for me. I hope it does for you.

From: John Landvogt 

=========================== end of section 44 ============================== 
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