contact printing

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Ok, here's another contact printing question. I recently got started in shooting and processing b/w as a sideline to my color photography. Since I don't have an enlarger yet I thought I'd start contact printing my 4x5 negs under a glass sheet using a 25 watt frosted incandescent bulb on a home made stand with simple metal reflector. Granted, a pretty ‘homespun' setup. Anyway, I printed on Ilfospeed RC Grade 2 paper, developing in Dektol in trays at 1:3 dilution for 2 minutes. After some experimentation I found I could only get a reasonable print by removing the reflector, setting the bulb three and a half feet above the neg, and using a TWO second exposure! The negs look good and I am absolutely certain that I mixed the stock and working solutions correctly and I developed at 68 degrees. Maybe my choice of papers, light source, or developer is not ideal for contact printing, but I thought this combination would give reasonably ‘normal' results, at least for experimentation. Am I missing something here?

Many thanks in advance for any responses!

-- Andy (akkup@mindspring.com), December 16, 2000

Answers

Andy, I'm not sure of what your problem is. Exposures too short?

I am using a similar setup. I use a old Kodak safelight with a 15 watt bulb 4 feet from the neg. My starting time with Polycontrast RC is 2 seconds as recommended by Kodak for that arrangement. I use Dektol 1:2.

-- Bill Brady (wmbrady@olg.com), December 16, 2000.


I'm not sure what the question is... Do you want your exposures to take longer? Raise the bulb, go to a lower wattage, or devise some sort of waterhouse stop arrangement.

-- Chad Jarvis (cjarvis@nas.edu), December 16, 2000.

You can also use Azo, which is designed for this kind of contact printing, and is much slower than conventional enlarging papers.

-- David Goldfarb (dgoldfarb@barnard.edu), December 16, 2000.

Andy, There is nothing strange about your results. I have a similar set up for proofing away from home. I use two thicknesses of typing paper taped over the front a a deep reflector with a 25-watt bulb about 4 feet from the paper. Exposure times range from 5-12 seconds depending on the neg. Your bare bulb is just too bright. I'm sure you can find something to attenuate your light source with in order to lenghten the exposure time somewhat. Hope this helps, ;^D)

-- Doremus Scudder (ScudderLandreth@compuserve.com), December 16, 2000.

Another option is to put the bulb on a dimmer and reduce light that way to provide a longer exposure. This does change the color temperature of the light.

The time issue isn't too important for proofing...but if you wish to do some local burning/dodging for more refined prints, then more time helps.

-- Fred Leif (frederickl@aol.com), December 16, 2000.



I guess my original post was a little vague. Basically my question is, would my results be considered typical? To my eyes the light source is very dim, I would have expected a much longer exposure. Thanks for your answers, it seems my results are not as strange as I expected.

-- Andy (akkup@mindspring.com), December 16, 2000.

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