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    FAQ or Answers to Frequently Asked Questions                  Section 43
            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 43 and its contents are listed below.
    43.01  -< Instructions for using a Gossen Luna Pro F light meter >-
    43.02  -< On Taking Yourself Seriously by David Vestal >-
    43.03  -< MacGyverish tools used by photographers >-
    43.04  -< How to make Public Relations photographs at school >-
    43.05  -< How to compensate for use of "minus" diopter lenses? >-
    43.06  -< Instructions for making one's own print washer >-
    43.07  -< Processing FORTE film in Kodak developers >-
    43.08  -< Determination of actual focal length of view camera lenses >-
    43.09  -< Are obsolete flashbulbs available anywhere? >-
    43.10  -< Another go at Film Acceleration >-
    43.11  -< Developing in ascorbic acid - tips and hints >-
    43.12  -< D-25 developer >-

43.01    -< Instructions for using a Gossen Luna Pro F light meter >-
> Could anyone share with me some brief, abbreviated instructions for using a 
> Gossen Luna Pro F
Make sure the battery is good. To test, push in large red button on left and
then push in small green button on right. The needle should go well into the
"batt" zone. Are you using it properly? One idiosyncrasy is that the meter will
give flash readings in all three (reflective, incident, and flash) modes - but
only accurate in flash mode. To measure for a single firing of your flash do
the following: Make sure ASA is set for your film. Make sure exposure
compensation dial is set to zero (small black tab on outer ring edge
- it will line up on a mark just to the right of the green marking "LW/EW".
Make sure battery is good - push in large red button (on/off switch), and then
push in small green button on right. Make sure the meter is set for single
flash (white dot on large red button is to left). If the button is to the right
it is then set for multiple cumulative flash readings. Make sure meter is set
to flash mode (small red button is out - button in puts meter into
incident/reflective mode). Make sure dome is over photocell, aim meter at
flash, and fire flash. The needle will then move. Simply turn round dial to
center the needle on zero. Take your reading from the little red flash sign on
the dial (located between 1 and 2 second mark). You should then have an
accurate reading. Hope this helps. Typically Luna Pro's are reliable, accurate
meters. I have 2 that I constantly use (and trust at weddings). Good luck. 
Steve Crist -- CristPhoto@aol.com

43.02       -< On Taking Yourself Seriously by David Vestal >-

I read the following words-of-wisdom (in my opinion) and have been saving them
for many years in a file cabinet which I emptied today. In light of the present
discussions on the list I thought they might be appropriate to share since I
believe there is a ready application for them in photo courses as well as
professional situations. I am posting this with what I hope would be the 
blessing of the author although I have not been able to contact him. 
Andy Davidhazy - andpph@rit.edu
On Taking Yourself Seriously
By David Vestal - as it appeared in Popular Photography magazine
One of this century's livelier art movements was Dadaism, which began in
Switzerland during World War I. Dada was mainly negative and took an anti-art,
anti-rational stand. Dada works were meant to shock, but most of them were
purely silly. In this it was prophetic (look around).
In its futile way, Dada was an apt response to the world of 1916, as it is to
our own: foolishness in answer to craziness. Sorrow and anger are unavoidable
and just, but they do not turn evil into good. The hell with reproach, then.
Ridicule fits better. The Dadaists regarded the world as a stupid joke - a
viewpoint that's hard to argue against.
My favorite act by the Dadaists was when they expelled one of their number for
taking himself seriously. Did they realize that in doing so they were taking
themselves seriously? I like it.
I have noticed that in photography, whether it's a photographer, a critic, or
whatever, one thing usually goes with quick recognition and what is called
success: the person takes himself seriously to the point of obsession. Nothing
else is allowed to matter as much.
The required insane belief that you are more important then anyone, and that,
as a result, your work is more important than anything, cannot survive
intelligent scrutiny; but it is hardly ever asked to. And it's one of the most
effective sales devices on earth: even when it's mistaken, total conviction is
Sometimes it isn't conviction, but simply a bold lie. The more preposterous a
claim is, the harder it is for honest people, who feel ashamed when they lie, to
disbelieve. This may be why absurd and stupid photographs get so much attention
and applause. People just can't believe they're as bad as they look, although
they generally are. It's easier to ignore and dismiss good work for which no
great claims are made; and that's what happens. Art history consists largely of
I'm not against ego except when it runs wild, but I recommend cultivating a
sense of proportion. You may come to see that however much you like your own
work - as I like mine, for instance - it won't save the world. Photographing
makes little difference as the rest of the things people do: we live and die,
and the world goes on. When you realize this, you may not be able to take
yourself seriously enough to make a career of it. I hope so. 
This has good and bad sides. Good: It lets you take your pictures seriously
instead of yourself. You look at them critically as well as fondly and reject
the ones that don't work. This helps, because those who think they can do no
wrong have a blind spot that leads them to accept poor work. 
Your work may well be as important as anyone else's; but how can anyone tell?
Don't look down on others too readily, but look up to no one. This spares you
the need to imitate and to play at being important, leaving you free to work as
you choose without worrying about people's reactions. If you take your work
seriously enough to keep doing it as well as you can, regardless, that's what
seems to matter. 
The bad side is that photographs are made to be seen and felt by others, and
you may sometimes get the depressing feeling that no one will see yours. Then
what good is it? The only answer is that if you work sincerely, it does you
good to do the work. If nothing else pans out, that will have to serve.
I notice that Pissarro's paintings have now been discovered by the museums on
whose walls they've been hanging all along. The museum people just didn't pay
attention until now. They knew about Pissarro, but they didn't know him. Then,
apparently, after many years, someone said, "Wow! Pissarro!" and they latched
on. Our art authorities keep demonstrating that they're clods. Now they are 
busy selling Pissarro to the public, and they feel like pioneers. It's a Dada
I doubt that Pissarro took himself very seriously. He was known for helping
other painters, not for chasing after fame. You see the results.
I'm on some strange mailing lists, so sometimes I get letters written by art
photographers to tell collectors about their latest opuses. These letters are
models of pomposity, written in the third person for grandeur and sprinkled
with magic words calculated to impress and sell. No plain word is used if a
fancy one can be found. They go like this: "Mr. E. Gregious announces that as
of November 31 the price of his historic Blah-Blah Series will go up from $750
to $1,000 per print. "Mr. Gregious is presently preparing a definitive archival
edition, strictly limited to 100,000 sets, after which the negatives will be
retired, of signed, silver-gelatin chlorobromide prints of his celebrated
Yeah-Yeah Series, widely considered by informed connoisseurs to be among his
most significant images. In the words of the noted critic, I.G. Norant, "Int he
ontological paradigm with which they confront the stunned viewer, these Angst-
filled images form the ineffable quintessence of this transcendent artist's
"Exquisitely slipcased in antique buckram with an overlay of rare glazed chintz
and hand-laid, acid-free, rag-paper linings, these extraordinary images may be
viewed by special appointment at the artist's atelier."
And so on. I'm not exaggerating much. They do go on like that, and at much
greater length. Sometimes the pictures are fairly good; more often they are
Once in a great while the pictures are excellent. I can think of one very good
photographer who sends letters much like this. I don't know how he can stand
writing them.
If you're not a fraud, you have to take yourself awfully seriously to write
such bilge about your work. It's ridiculous and embarrassing, but apparently it
Sometimes I wish I could do it. More often I'm glad I can't.
When good photographers fall into this routine, I groan and wish them luck.
When the usual incompetents do it, I wish them justice, not mercy.
To picture buyers: When faced with the solemn and ludicrous pomposity of art
photographers and their dealers, ignore the pitch but look well at the
pictures. Don't try to impress anyone. Just follow your feelings; that's the
only way to judge pictures. And of your feelings, you are the only judge. No
matter what is said, buy the photographs you like and leave the rest.
To photographers: If you can possibly help it, don't take yourself too
seriously. If you can't help it, I can't help you. Either way, you're stuck, so
take yourself as you are.
posted here by Andrew Davidhazy - andpph@rit.edu 

43.03           -< MacGyverish tools used by photographers >-
> Rob Miracle said: "What are some of your favorite and somewhat obscure or 
> MacGyver'ish like tools in your bag?"

I was in the darkroom today and started thinking about my  burn/dodge tool and
how cool (at least to me) it is. It is about 18 years old.  I made it out of a
section of a coat hanger and duct tape.  I have a quarter sized loop on one end
with the duct tape making the loop opaque.  The other end is a pencil eraser
sized loop again with duct tape to  opaque the loop.  This device has remained
unchanged for almost two decades and is still going strong.
Rob --  Rob Miracle rwm@mpgn.com

I haven't done wet darkroom work for a while, but when I did one of my
favorite burning tricks was two pieces of carboard sandwiched together. The
bottom one was a larger board with a large hole cut in it and the top board
was a bit smaller with a hole the same size or smaller. The boards could then
be slid against each other to control the size and shape of the "aperture"
depending on the size and shape of the area being burned. I found it most
effective for those areas that a nice round hole didn't cover quite right.
Rich Mason -- RichPhotog 


Quite a few years ago when I lived at the western edge of Quebec, I had bought
a new house and had designed a custom darkroom from scratch. It had two Dursts
in it, a DA900 and a 138S, storage space, a fridge, stereo, but most
importantly of all ... a counter at the far end that was reserved for things
not photographic ... and what took absolute precedence on that counter was a
commercial cappucino machine, after all, if you are going to lock yourself out
of the world for an extended period of time . . . no one needs to know that you
are spoiling yourself rotten at the same time. Today, I live elsewhere, have a
new darkroom . . . no longer have the cappucino machine . . . but really value
the lock on the door, and the fact that through all these years I've had the
insight to forego a telephone jack anywhere near that I might be doing creative

Paul Aparycki -- 

I also have a couple of duct tape and hanger dodge tools. Along with
that I use a lot of nylon stockings. Several softeners used under the
enlarger light are made from embroidery hoops with nylons stretched over
them and I use nylons for filtering chemicals and water.
I use several old proof printers for printing 8 x 10 negatives (holds
the film and paper snug and doesn't allow the paper or negative to drift
when putting the glass down).
Marilyn Dalrymple -- dalrymple@truelink.net


Music. That brings up a subject that I need to ask about. I have recently
put small "boombox" in the darkroom. I usually have it tuned to an FM
station and it is running on batteries.  I have an old GraLab 600 timer.
I got it used in '79 and it was pretty old then. Of course, it had an 12
year lay off, but recently it seems that if I have the radio on, I get
power fluctuations in the timer (the power to the enlarger fluctuates). It
has always fluctuated a bit right as the timer was about to kick off, but
since that was predictable, I could adjust for the light fall off in the
last second. 
With the radio on (and on batteries, so its not plugged into the power
system), I get a lot of buzzing on the radio during these power fluxes.
If I am playing a CD, the buzzing goes away, and the power fluxes don't
seem to be as bad.  The boom box is along the same wall as the timer and
are about 6 feet apart. 
I don't want to blame the radio. Recently I started using the GraLab to
time my film development rather than my watch and I wonder if the extra
wear on the aging timer is predicting its pending failure? 
Rob -- Rob Miracle 

In terms of homemade dodging tool, I use wire hanger shaped into a  square. Use
thread from corner to corner, crossing in the middle,  with a bit of duct tape
(is there anything this stuff can't do?)  where the threads intersect. This
arrangement ensures I won't  accidentally leave the wire part over the
photograph for too long.
Given a choice between burning and dodging, I much prefer burning.  Dodging
well is a struggle for me.

To add to this now that I've just been to the darkroom, I thought of a few more

1. Extra shoes -- Even though I make it a habit to wear  comfortable shoes, my
feet and legs still sometimes need a change of  footwear. What works for me is
a pair of cork-soled sandals with a  high arch. When my feet start to complain,
I change into my darkroom  sandals (I also do this preventively). Even the
slight change in  heel height can rejuvenate my legs.

2. Shelf under sink or under enlarger counter -- Again, this is  for leg
comfort. Putting one foot up on the shelf for even a short  time is good for my
circulation. It's also good for storage space.  Those without a shelf could use
a low footstool that can be easily  moved out of the way.

3. Canned air -- I loathe spotting photographs, so I keep a can  of Dust-Off or
some other brand on hand to dust ALL negatives. I buy  canned air like I buy
camera batteries: before I need them. And I  always have a spare nearby. Also
related to clean negatives is a  technique I use for really seeing the dust on
the neg. I have a hard  time seeing dust on the neg, so after I put the neg in
the carrier  and insert it partway into the enlarger, I turn on the enlarger
light  (do not do this in a community darkroom, as your neighbors will  become
very upset with you. Also, make sure your paper is safe).  The angle of light
hitting the neg makes it easier to see any dust,  thereby making it easier to
blow away with the aforementioned canned  air. You will probably need to shift
the angle of the neg carrier  until you find what works for you.

4. I keep an old T-shirt in the darkroom to wear in there.  Aprons don't
protect my shirt sleeves from chemical splashes, so an  old shirt is a must for
changing into.  Using the darkroom is part of my job, so I need to look
presentable when I'm out of the  darkroom.
Colleen Valentine -- cvalentine@clc.cc.il.us
1. The too-dull-to-cut-fabric pinking shears from my wife's sewing box. They're
great for cutting dodging masks that have a soft edge.
2. A medium ball head mounted between a heavy metal base plate and a 5-inch
magnet from an old blown-out stereo speaker. When you have to save that
building photo where the verticals aren't quite vertical, the magnet holds the
paper easel firmly in place, and the ball head gives you some perspective
correction capability ... just be sure to stop down far enough so that depth of
focus covers the tilted easel.
Tom Lesser -- 

I 'installed' a dimmer on the circuit that runs my safelights so I can have
lots 'o light during pre-exposure preps then cut the brightness when paper is
out..... no 'safelight' is perfectly safe it seems.
William Scanlon -- 

>... my dodging tool is about 18 years old. I made it out of a section of a
coat hanger and duct tape. I have a quarter sized loop on one end with the duct
tape making the loop opaque.

If it's grey duct tape, then I have one too! (Well all except the pencil eraser
part, I'll have to try that next!) I guess it's just what you happen to have on
hand at the time. I had thought about cutting a wafer off the bottom end of a
champaign cork and spearing that with a bicycle spoke, but the bottle wasn't
opened at the time (and if I had opened it then I woulda forgot to look for the
bicycle spoke.) The other "tool" that I use all the time is my burn-in card
which is one of those black plastic-coated pieces of cardboard that I saved
from a pack of paper that has a dime-sized hole reamed into it (jaggy edges and
all --- I believe it results in a softer penumbra (at least I think that's the
term) than a sharply cut hole.) Another "tool" that I have, but don't use that
often, is a piece of transparent, gray acrylic which I found in the remnant bin
at my local plastics supply outfit. I use this when I need to dodge, but also
want to impart some softness to the thing that I'm dodging (usually for stuff
in the background that I don't want to be distracting.)
-geoff -- geoffrey.kim@ac.com

43.04      -< How to make Public Relations photographs at school >-

>I have to make some public relations type photographs in the school my child
>goes to. Any tips especially reagrding lighting and what to photograph?
>I thought that I would not try whole class shots as I imagine I will end up
>with a lot of shadow problems ( as I only have flash ). I thought that
>maybe I could get in relatively close ( say 4 - 6 foot ) to the subject (
>kid drawing - playing an instrument etc ) and I could mount the 300EZ
>remotely - maybe 3 - 4 feet left/right and use the other flash/slave set up
>as a fill in fired across the subject from the opposite side as the 300EZ.
>I would set the fill in flash further back and diffuse/soften its effect
>because I do not want a white out and I do not know how powerfull it is ( I
>do not think that it is as powerfull as the 300EZ ) I do not mind spending a 
>little money on this but I do not want to buy an elaborate set up as I prefer 
>outdoor shots to indoor. All of the classrooms have flourescent lighting - do 
>I need any filters.
A good lab can balance out most of the problems with flourescents. Also
depending on the bulbs, they may not be that out of whack.
You actually, have a couple of questions here. The first deals with how to take
indoor shots, and the second is "what to take". I'll address the first, first
Since you said you have an EOS 50E, and since I am unfamiliar with the Canon
line when expressed in non USA names, I assume its either an A2E or an Elan
IIE, so either should be able to do "fill flash" with their built in flashes,
or the 300EZ. 
Here is the catch. If you fill flash under flourescents, the lab won't be able
to balance the shots. The subjects will be hit with two different color lights
and you will get some bizarre colors. Its not bad, but expect it. So you can
use full power flash and overwhelm the flourescents, or accept the natural
light of the scene and let the lab do its thing.
Now for my advice on the lighting. Use either Fuji 800 or Gold Max. Shoot
natural light. In particular focus on classrooms where you can open some
windows and use some daylight to help out and forget the flashes. You may even
need to shoot Fuji 1600. Since this is going out in a brochure, the grain isn't
going to be a problem because the half-tones will hide it. You may need to
shoot slides depending on the printer. If you have to shoot slides and you
don't have any windows to balance the light, then you will probably need a
filter to correct the color. Also slides are going to be slower speed, and with
your lens setup you may be forced into using the flashes.  If the printer can
work with prints or the negatives, then you will be in good shape.
Since you are supposed to take candid's, you don't want to be rigging lights as
you will loose the candidness of the shots. You want to capture the essence of
the school and there is no better way to do this than not involve yourself in
the activity being photographed.
Now for playground and sports, this isn't a problem. You will be pretty much
ignored. But in a classroom setting, your mere presence will disrupt the
natural flow. Work it out with the teacher and let the class know that you will
be taking pictures and to go about their normal business. Then go about your
business while the class goes about theirs. After a bit, they will forget you
are there and you can get your candid shots.
What to shoot? My shoot list would include:
Indoor Shots:
Teacher and Student in a one-to-one at a desk.
A Shot from the back of the classroom, looking up to the teacher working at
the chalk board.
A whole class shot (may not be used, but get it any way)
Two or three students interacting in a group learning situation.
A student looking over a classroom object like a microscope, model of the
brain, etc.
A student working at a computer or students collaborating at a computer.
Depending on the age of the students, some interaction at the lockers.
A long telephoto shot of two students walking down the hall.
A Cafeteria Shot.
Outdoor Shots:
If the school has some statue that identifies it. Our elementary schools
mascot is a tiger and they have a tiger statue in the front of the school.
If your school has one, get some kids playing/studying around it.
Students studying on the grounds
Kids playing on the playground
Kids participating in PE or some other athletic game
A posed shot of some kids and a teacher at the school's sign if they have
one, waving to you.
Then grab some other shots.
Rob Miracle 


Unless you are very used to the power output of your flashes I would
keep the fill flash straight on so to prevent cross shadows. Make sure
that you know the range of the press you will be using so that you know
how much fill to give. If you do not have enough fill you will see the
shadows on film but they will go black when printed on the press. You
generally have about a 4 stop range on most presses When I shoot 35mm I
set my fill flash to -1 2/3 stops .  In your case using 2 strobes you
will also need to make sure that you get some of the available light or
you will have a black background all around the child.
You could also gell every thing but it will cut the power of everything
by about 2 stops.
What I mean is a 30Magenta CC on the lens with a 30Green cc over the
flash with lets the lens correct for the lights and makes the flash
match the flouresents

Randy Little -- 

43.05    -< How to compensate for use of "minus" diopter lenses? >-
>I'm going backwards and will be shooting with an old Seneca 4x5 with a very
>long belows. Using a Plasmat convertible lens which has a maximum of 350mm 
>(or is it 320 mm?)., When using minus dioptar add-ons to increase the focal 
>length combination, how do I compute the new f-stops? The bellows gets bigger 
>and therefore the f/stops that are marked on the lens are not what they say. 

I would use bellows extension factor.
Bellows Extension Factor = (Bellows Extension) squared / (Focal Length) squared
Bellows is calculated from the middle of the front standard to the middle of
the rear standard.  The focal length must be converted into the same units as
the bellows.  For example 10 mm = 1 cm.
Example Problem - assume this:
6 in. focal length lens
9 in. bellows extension
So:   9x9 = 81
      6x6 = 36
      81 / 36 = 2.25

Approxiamately one stop.  Add that to original f# stop.
Sam Hill -- 
----------------------------------  cut  ----------------------------------

I would approach this by comparing the NEW (with - diopter on lens) Distance
from lens to film to the OLD (without - diopter) distance from lens to film 
and make some reasonable adjustment as follows:
NEW F stop = F stop you set on lens times (NEW distance divided by OLD 
distance) squared.
lets' check .... I have a 320 lens and will use it at f11 and I measure 320 mm
from the film plane (with lens focused on infinity) forward to some point
(hopefully) over the lens barrel. Now I place a negative lens on the prime lens
and refocus the camera and find that the new distance to the previous spot is
620mm (I made the numbers easy to work with).
So, f11 times (640/320)^2  is 11 times 2x2 = f22 ... an effective loss of two
stops which makes sense since I have kept the aperture the same but doubled the
lens to film distance.
Another way is to find the new effective focal length assuming the prime lens
is a "simple" lens (assumption can usually be made safely). What I need to do
is add the two focal lengths to find the combination ...
lets's say I use a -3 diopter lens on a 320mm prime lens ... hmmmmm
  1/f1  +  1/f2  =  1/fcombination
the focal length of a lens in diopters is its reciprocal in meters so ...
a -1 diopter lens should be a  -1000mm, a -2 should be a -500mm and a -3 should
be a -333mm (let's call it 320 for now)
  1/320  +   1/-320  =   1/0 or infinite ... essentially the negative lens
cancels out the positive one! so I guess using a -3 diopter lens on a 320mm
prime lens is not practical!!!
ok let's switch to a -1.5 diopter lens ... a - 660mm fl (or about -640!!)
  1/320   +  1/-640   =  1/Fcombo 
  2/640   -  1/640    =  1/640    0r   640mm
if I had a f11 lens before its diameter was 320/11 or about 30mm ....
640 divided by 30 is about 22 so the new aperture is f/22
I think anyway ...
andy davidhazy - andpph@rit.edu

43.06    -< Instructions for making one's own print washer >-
>We are looking for a new print washer for our darkroom to rinse up to 
>11 x 14 prints. Can we make our own?
The key word in your email is rinse. Most photographers and sales people
with whom you discuss your darkroom situation with will assume you mean a
print washer to wash your prints. In my answer I will assume we are talking
about just getting some of the excess fixer out of your prints and not washing
them as a final wash for print longevity. This is what our photo students do
at our high school where I help out as a darkroom tech. The prints they
really like go back for a final wash later. We only use RC paper.
RC paper and fiber based paper can successfully be rinsed in the same design
washer. Look for a washer which will keep the prints in constant motion or at
least have moving water reach both sides of the paper. RC prints will want to
adhere to each other. I would not consider a square sided plexiglass archival
washer for RC prints. The prints will adhere to the side walls and dividers.
The archival washers are great for fiber papers. I am unaware of washer
designed for the washing of RC papers. In my personal darkroom for my
commercial work, I use a 24 inch Richards washer for RC. It makes a nice
whirlpool but it is good for only up to three 8x10's at one time. More than
that and they stick together. You would need a 36 inch model to do 11x14's
and still probably not be able to do more than 3 prints at one time.
For rinsing your prints I think you will have to consider a circular washer
whether home made or purchased. If you really need to have up to eight 11x14
prints in it at one time then the unit will be big. Also you will have to
watch over them while they are being rinsed and keep the prints separated by
A better idea might be for you to decide to wash/rinse the prints one at a
time after they come out of a water bath holding tray. A single print
washer/rinser need be only a little larger than the print itself. If you are
washing/rinsing a single print, the wash time can be very short. If the flow
of water across both sides of the paper is good, an adequate rinse can be
achieved in one minute for RC and two minutes for fiber paper. Three minutes
is considered a full wash for RC papers by most manufactures, and would be
adequate for most class assignments as well as portfolio and school year
display work.
If you were to build a single print wash/rinse unit, consider the following:
The unit can be rectangular like a tray and would need to have a good flow of
water entering at one end through 10 or 15 jets (1/16 inch drilled holes) in
a PVC 1/2 pipe. The jets can be drilled as to aim a water flow across the
top of the print and also aim a water flow under the print. The water would
exit out several large 3/4 inch holes drilled on the opposite wall. These
exit holes would be placed so the wash water depth will maintain itself at
about 2 inches. If the print sinks to the bottom and wants to adhere itself
to the bottom, install another 1/2 PVC pipe with jets to blast an additional
water flow across the bottom of the unit to lift up the print. A baffle or
dam should be fastened across the exit end about one inch in front of the exit
holes. This bottom edge of the dam will be about 1/2 off the bottom of the
unit. The upper edge of the dam will be higher than the water level. The
dam's purpose would be to force the water to exit the print washing area at
the bottom of this washing area. Fixer is heavier than water.
Before building such a unit out of fiberglass over wood or 1/4 sheet PVC look
at the bussing trays for dirty dishes used by restaurants and maybe your
school's own cafeteria. They are usually made of a tough heavy chemical
resistant plastic and measure about 12 by 18 and are 6 inches deep. They are
cheap. I use several of these trays in my personal darkroom for a variety of
purposes. They are made by Rubber maid and others and can be purchased at
Janitorial/Food Service supply houses. Look in the Yellow Pages.
If you are successful with building a good washing devise, such as the one
above which I dreamed up as I typed, then go on the Internet and sell them. I
don't believe anything like it is on the market. "The Norse North Seas

Thanks for this excellent suggestion. I have a Zone VI Archival washer ( with
removable plexiglass dividers and I have several 6ft. strips of plexiglass
1/4" bars. Now why didn't I think of that? 

Walter Holt - NETHERHOLT -- 

43.07          -< Processing FORTE film in Kodak developers >-
         Processing instructions for FORTE films in Kodak developers
               all times at 68 degrees F,  all times in minutes
                       D-76      D-76   1:1   Microdol-X 1:1  HC110 Dil B
35mm films
Fortepan 100           5.25         6.75           12            4.6
Fortepan 200           5.25         6.75           12            4.6
Fortepan 400           7.5          9.25           16            7
120 films
Portrait Pan 100       5.75         7.6            14            5.25
Fortepan 100           5.3          7              12.5          5
Fortepan 200           6            8              14.3          5.5
Fortepan 400           7.60         9.5            16.5          7.3
* Small Tank processing is based on 8 to 16 oz of developer per roll.
* Agitation should be continuous for first minute and then 5 to 7 inversion
  cycles in a  5 second time span every 30 seconds for the remainder of the
  development time.

From: RTesn79923@aol.com

43.08    -< Determination of actual focal length of view camera lenses >-
> I need a method to check the actual focal lengths of view cameras. All
> manufactures stamp approximate. values for focal lengths on their lenses. 
> I need a simple method to determine true focal lengths.
The way to do this is to focus the lens at infinity, mark the position of
your focussing standard on the rail (or bed, or whatever), and then rack
out the focus to 1:1. You have to do this accurately; obviously you focus
on a precise rule or something, and then measure the image on your ground
glass with another rule which is also known to be accurate. Mark the
position of your focussing standard again. The distance between the two
marks is your focal length. This works for all lenses that do not have
floating elements.
Henning J. Wulff - henningw@portal.ca 
One simple method is 'Conjugate Positions'.
Set up an illuminated source (such as a sheet of card with a few  pinholes in
it in front of a lamp) and screen, separated by a  distance larger than 4 times
the focal length being measured.
With the lens in the middle there are two positions where the source  is
focussed on the screen, one enlarged, the other diminished.  
          The focal length is given by f=(D^2 -d^2)/4D

where D is the distance between the source and screen, and d is the  distance
the lens is moved between the two focussing positions.
This will covet both thick and thin lenses, as you only measure the  distance
the lens is moved to obtain another focus.  DO NOT REVERSE  THE LENS BETWEEN
If you use several values of D you should always get the same f.
(I cheat with this, I have an optics lab across the passage with  optical
benches to use.)
Jim Thyer 


There are several ways to do this but whether acceptable any one is depends on
your criterion of accuracy. I can think of a couple of ways of doing it
roughly. One is to compare the image size produced by your lens of unknown
focal length to the image size produced by a lens of known focal length (this
could be a simple lens!) Typically you want to be working with objects located
far from the camera lens.
A method that I thought was rather ingenious (but which works only with
non-distorting lenses) goes as follows: Place a groundglass in the focal plane
of the camera (does not have to be a very good one, probably wax paper or
translucent paper will do) and measure the width of the film gate (it should be
close to 36 mm). Now, fixing a piece of paper on a table or other flat surface
place the camera on it and keeping the shutter open aim the camera at  some
distant subject. Make sure the lens is set to infinity focus. Adjust the angle
of the camera so as to place its image at one side (let's say the right side)
of the film gate. Draw a line guided by the camera base onto a piece of paper
located under the camera. 
Now turn the camera so the subject's image is at the other side of the gate.
Draw another line on the piece of paper under the camera. You should find that
the two lines you drew intersect at some angle. If you bisect this angle and
draw a line equal to the width of the gate (which you measured earlier) so that
it is perpendicular to the bisecting line and touching the intersecting lines
at each side, you will find that the distance from this line to the vertex is
equal to the focal length of the lens in question.
andrew davidhazy -- andpph@rit.edu

43.09          -< Are obsolete flashbulbs available anywhere? >-
>I have an old camera and an old flashgun. Where can I buy flashbulbs?

Compact and more powerful than most electronic strobes, flashbulbs offer ease
of use without a lot of equipment or access to a wall outlet.They are being
used for general photography, photographing trains, underground caves, by
divers underwater, scientific research, by testing companies, for stage and
motion picture effects, model rocketry, high speed filming, laser research,
marching bands, and silk screeners to name a few.

You may be able to buy them from Cress Photo, a division of Lite Station USA
Inc. PO Box 4262, Wayne New Jersey 07474-4262 Tel: 973-694-1280  Fax:
973-694-6965 on the web at: http:// www.flashbulbs.com

43.10         -< Another go at Film Acceleration >-
> I have heard of "film acceleration" and the strange and unexpected colors 
> one can get but I don't understand how to achieve this.

Shoot EPP at iso 1000 Process in D-76, Stop it (no fix) then wash.  The 
dry it recan it and have it processed in c-41

The timing for the B&W is the tricky part.    This is a technique Nick 
knight used a lot a few years ago(early (90's)
From: little 

43.11       -< Developing in ascorbic acid - tips and hints >-
> RE: ascorbic acid developer. I need some hints, tips as to its formulation 
> and use. Specifically I would like to try to get the borax as high as 20-30% 
> and the ascorbic acid to 10%. Could the phenidone be safely reduced to 0.1% 
> without risk of oxidation?  Would the addition of small amounts of some 
> chemicals extend their useful life?

The practical limits of solubility of borax is about 25 grams in 1000mls.
of water at room temperature, for ascorbic acid, it is appx. 40 grams for
the same amount of water. Another subscriber has already commented on the
ascorbic acid going bad in solution, due to its characteristic as an oxygen
scavenger. How ever, you might consider making a sodium metaborate stock
solution and using this instead of a seperate NAOH and borax stock.
The author wittingly, or unwittingly, with his formula, is forming
sodium metaborate in solution by combining NAOH with borax. His formula is
using appx. 8 grams of sodium metaborate as the accelerator when all is
said and done. You can make a 20% sodium metaborate stock by doing the
            water                           700 mls.
            borax, 20 mule team             165 grams

This of course, will not fully dissolve in room temp. water.
Dissolve it as well as you can, then add:
            sodium hydroxide (red devil lye) 35 grams
The addition of the lye will dissolve the borax, and will form
sodium metaborate in solution. Add:
            water to make                    1 liter.
Now, when you make the developer, proceed as follows:
For use, to make 1 liter:
1.   Start with 800 ml. of water
2.   Add 40 mls. of 20% sodium metaborate solution
3.   Add 2 grams vitamin C crystals
5.   Add 2 ml of the 1% phenidone solution
6.   Add water to make 1 liter
7.   Develop film as with straight D-76 (your mileage may vary).
Lowering the phenidone to a 0.1% solution has the problem of needing a
very accurate balance to measure 0.1 gram of phenidone. I would imagine
also, the 1 gram of phenidone in 100 mls. ethyl alcohol would have better
keeping proerties. If you went with the 0.1% solution, you would then need
to add 20 mls. of that to the working solution, rather than 2 mls. as with
the 1% solution.
One other thing about ascorbic acid-it can be substituted in (virtually)
any formula that requires hydroquinone by using 40% more ascorbic acid in
place of the hydroquinone. For example:
                     Vitamin C-72 paper developer
 water                            750 mls.
 metol                              3 grams
 sodium sulfite                    45 grams
 ascorbic acid                   16.8 grams (can be rounded up to 17 grams)
 sodium carbonate (mono)           80 grams
 potassium bromide                  2 grams
 water to make                      1 liter
 Use as you would normal D-72 or Dektol.
Exceptions to this would be developers using hydroquinone as the soloe
developing agent, or concentrated developers (like my hot shot formula)
that the amount of ascobic acid called for would not go into solution. Hope
this helps.
From: mdmuir@nfinity.com (Maxim M. Muir)

43.12                      -< D-25 developer >-
> What is D-25 developer? How do you use it and what are its advantages?

D-25 is merely D-23 with a small amount of Sodium Bisulfite added to
reduce the pH, thus slowing down the development time.  This allowed
the 100 grams of Sodium Sulfite in the developer more time to dissolve
both developed silver and Silver Bromide grains.  The lower pH also
reduced emulsion swelling and thus reduced the amount of grain clumping.
None of today's emulsions require such extreme measures to achieve acceptable
grain.  Typically, one was instructed to expose one more stop when using
D-23.  For D-25, a SECOND stop was needed for full exposure.  
Thus, the film had to be rated at about 1/4 of full speed.  A disadvantage of
processing in either developer, but especially of D-25, is the tendency
of the dissolved silver to replate itself randomly on the developing
grains, thus "muddying" sharp contrast boundaries and reducing acutance.
Obviously, a better solution to fine grain is to use any of the many finer
grained films now available, but undreamed of in D-25's heyday.
I would suggest that if your goal is unblocked highlights, you try either
Microdol-X or Ilford Microphen at 1:3 dilution, using the time recommended
for the film chosen in the Microdol-X, at 75F.  I have used this happily
for years, and highlight blocking has never been a problem.  In Microphen,
the film can be exposed at full rated ISO with good shadow detail.  The
Microdol-X is inherently about 1/3 to 1/2 stop slower.  This appears to
be a very common trait of developers made with Phenidone when compared to
those made with Metol.
Another solution to highlight blcoking is the use of a divided developer.
One of the best ever is the Leica Divided Developer, first published
in 1927 or 28.  It is as follows:
Solution A:
Water (125F/50C)          750 ml
Metol(Elon)                 5 gm
Sodium Sulfite(anhydrous) 100 gm
Water (cool) to make     1000 ml
Solution B:
Water                    1000 ml
Sodium Sulfite (anhyd)     15 gm
Sodium Sulfite (anhyd)      6 gm
Time in Sol. A: is from three to six minutes, with a preliminary prewet
and using the longer times for faster films, the shorter for slower films.
Agitation is as normal; an initial time of continuous agitation followed by
5 seconds each 30 seconds.  Solution A is then poured off and saved for
reuse.  Solution B is then poured in and agitatated continuously for three 
minutes.  It is discarded.  DO NOT USE an acid stop bath!  The sodium
carbonate could gas in the emulsionm, increasing grain.  Instead, use a
two minute running water rinse.
This produces a real speed gain over D-76, yet with finer grain and
well-compensated highlights.  As I use mainly T-Max100 or PX, I usually
reduce the amount of Sodium Sulfite in Sol. A to 50 grams, reducing greatly
the solvent action of the Sodium Sulfite for a visible increase in 
sharpness.  It seems to have no serious effect on grain in TMX at all.
You apparently already have the Metol and the Sodium Sulfite.  The 
Sodium Carbonate Anhydrous is sold as ordinary swimming pool alkali,
at any Home Depot or similar store.  It's plenty pure enough for
this use.
I hope this does you some good.  Best of luck, and Merry Christmas!
From: Ed Lukacs 

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