Contrast on prints

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I recently finished my darkroom setup and have printed several images. I find that they are lacking in the rich black tones that seem to make so many photographs interesting. They also appear to be quite grainy at 8x10 size. I have seen the same problem on both rolls. The film was Tri-X developed in T-Max, and the negatives do not appear to be "thin". The paper is Kodak Polycontrast II RC.

Should I be over exposing the negative or is there some other reason for my problem?

-- Edward Feltman (efeltman@worldnet.att.net), December 03, 2000

Answers

Hi Edward,

I have no way of knowing what experience you have in printing, so I risk providing info that you already have, but here are the basics: You need to know how black your paper can potentially get. The way to do this is to expose a sheet of paper in strips, e.g. strips of 5 sec exposure by moving a piece of cardboard over your paper while exposing it through your enlarger. Ideally you would do this while having a blank piece of your film in the enlarger, so you can find out maximum black for your film with that paper at that level of enlargement and variable contrast filter and specific f-stop for that lens at the same time. Max. black will indicate how intense a black you can actually get. My guess is that while printing, you over-expose and under-develop. Your exposed paper should be in the developer for at least 90 seconds for the paper to get fully developed. Always adjust your exposure of the paper to get desired results, rather than adjusting development of the paper. Finally, you must use polycontrast or multigrade filters with a B&W enlarger with the paper you use, or change constrast settings with dedicated variable contrast enlarger or colour enlarger. Good luck.

-- Paul (pauloosthoek@hotmail.com), December 03, 2000.


I notice you're using Polycontrast II, which I believe hasn't been made in a while. If it's old paper it may be a bit dingy- pick up a new pack of III RC or similar. I assume you have fresh print developer correctly diluted. Understand what Paul said as you can't get good blacks if the paper never receives enough light to hit a reasonable density, nor if you underdevelop it. Now I'll play devil's advocate and say that good prints rarely achieve *absolute* maximum black, just something near it. As a practical matter, it's difficult to get the midtones right and still hammer the paper hard enough to get maximum black. Fortunately, it takes a densitometer to tell the difference. Flare will contaminate your blacks, so clean optics and a lens shade have to be part of the equation. Lighting and balance of the original scene should also be considered. As for the grain, Tri-X is great stuff, but grainy. In the back of my '99 Kodak catalog there is a chart showing the relative differences between developers. TMAX developer gives good shadow detail and moderate acutance, but not fine grain. It's good for pushing. Try some dilute D76, or maybe a finer grain film if the grain really bugs you. Oh, check the cleanliness of the enlarger lens too- both sides!

-- Conrad Hoffman (choffman@rpa.net), December 03, 2000.

You don't say what negative size you are using, so it's hard to say what effect you should expect at 8 x 10. However, the most common problem to cause excessive grain is over development, followed by over exposure.

Both of these problems, and especially both combined, can lead to excessive density, which would make it hard to get a deep black.

If you like Tri-X (and I always have), try D-76 @ 1:1 dilution, or a divided developer (Divided D-76 or Divided D-23). It is virtually impossible to over develop with a divided developer.

I would look to your film developing & exposing before I searched out a problem with the paper. However, printing at extremem contrast will always exaggerate whatever grain there is.

-- Charlie Strack (charlie_strack@sti.com), December 04, 2000.


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