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Film: Question concerning contact sheets

Nick Masson

New member
Hey all,
I've recently decided to go back to shooting B&W film, and i've been brushing up on technique and theory since it has been so long since i've been in the darkroom etc... I was wondering if anybody could answer a question for me regarding contact sheets:
If a contact sheet is made on standard multi-grade paper, will the densities in the print be close enough to those in the negative that you can critically assess the quality of your negatives?

I've always used a contact print just to take a 'look' at the negatives. I know the best way to judge the quality of a negative (detail separation etc...) is to look at the negative itself, but I have a hard time inverting a negative in my head, and don't really feel inclined to practice to the point where i'm proficient. I would love to be able to just make a contact print of my negatives, and know that the silver emulsion densities in the print are very similar to those of the negative (or, I guess more precisely, the exact opposite); so that I can use a loupe to assess the quality of negatives (eg. compare negatives when bracketing etc...).

Thanks!
-NICK
 
The way to make a contact positive on multigrade gelatin-silver paper that tells you the truth about your negatives is to make a proper proof.

The way negative transmission densities translate into positive reflection densities can be entirely discretionary but there is fixed point of reference: the edge of the film (or the space between frames) that got no exposure at all. This clear part of the negative must correspond to black in the positive.

A proper proof results when the contact exposure is the minimum to just make the film edge come out maximum black. I use grade 2 on multigrade papers for doing proper proofs. This is a middling contrast grade that serves to identify if your negatives are non-normal.

A proper proof shows the following:

If the positives are too dark or lacking shadow detail the film has been underexposed.

If the positives are too light or have burned out highlights the film has been overexposed.

If the positives lack contrast the film has been underdeveloped.

If the positives are too contrasty the film has been overdeveloped.

If the positives look good you've got the first step in making a fine photograph.

There are combinations involving multiple sins (underexposure and overdevelopment, for example) that a proper proof will alert you to if you read it right. Take notes, compare what you got, how you metered, what you shot, and how you processed. Change one variable at a time, keep experimenting until all your contact sheets look beautiful. Persistence and discipline make the learning curve to good negatives rather short.
 

Nick Masson

New member
Hi Maris,
Great, thank you for the reply. I was trying to figure out if a contact sheet, or proof sheet, would be sufficient to determine whether I wanted to print a negative or not (i.e. assess it's quality), and it seems from what you are saying that if I make the proof sheet correctly then it will be a fairly accurate rendition of the negative's densities and values.

So when you make a proof sheet do you use test strips to find the exact exposure necessary to render to inter-frame negative material a pure black? I used to just use a set f-stop and time on the enlarger, but it seems that to make it precise (from enlarger to enlarger etc...), you would have to do test strips...

Anyway, thanks for the info!

-NICK
 
Hi, I don't if that helps but when I used to work in the darkroom, one of my first task was to cut the 18*24 (cm) paper that I used to print the contacts with in 8 equal sheets. After I made my contact sheet, I used to print all readable (not only good or in focus) images and print them well without masking, it gave me an rough idea, because I've never been able to read the lack of grey transitions in a contact sheet (too sharp, too contrasty etc...). I also used to note the number of the film and the number of the image on the back with a pencil. This was my start to think about cropping, masking etc....


PS: Now i'm thinking that If I had the idea at the time to glue them in 2 or more 18*24 sheets of paper, It would have given me giant contact sheets to work with...stupid me! :)
 

Nick Masson

New member
Cool, sounds like a good process. I think i'll probably try something similar, and find my ideal workflow given time and money restraints...
Thanks!
 
Hi Maris,
So when you make a proof sheet do you use test strips to find the exact exposure necessary to render to inter-frame negative material a pure black? I used to just use a set f-stop and time on the enlarger, but it seems that to make it precise (from enlarger to enlarger etc...), you would have to do test strips...

Anyway, thanks for the info!

-NICK

The first proper proof I did needed test strips to catch the first appearance of Dmax.

After that I marked the enlarger (used as a convenient, controllable light source) with a sticker showing lamp-house height, lens aperture, and exposure time. This "calibrated"enlarger delivers proper proof exposures unless I change the brand of photographic paper, change the film to one with a different film base+fog density, or change the paper developer. Then it's back to test-strips again.
 
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