I took a B&W printing course about 15 months ago and the instructor recommended using filters (eg: a yellow filter) to enhance contrast when exposing film and to facilitate contrast control when making prints.

I began using a medium yellow filter w/ B&W film and have been happy with the results. However, I'm wondering if this is the best way to achieve contrast control, when using M lenses, which already exhibit more contrast than most other lenses. In particular, I'm wondering if using a yellow filter is degrading the quality of the extraoridnary M lenses. If so, then perhaps I should be looking for other methods of achieving contrast control.

I'll appreciate any comments.

-- KL Prager (www.pragerproperties@worldnet.att.net), March 06, 2001

Answers

KL, filters accomplish contrast control by freely passing their own color, and closely related colors; while rejecting light of the complementary color. So for a black and white shot of a yellow sail against a blue sky, the yellow filter increases the density of the sail's image on the negative; and decreases the density of the blue sky. In the print, this gives us a light sail against a darkened sky.

But using a yellow filter isn't a blanket recipe for good contrast. It won't do a thing for a scene that consists only of gray shades. It probably won't do much for an architectural shot of a white building with a gray slate roof, either. In other words, filters work by discriminating colors. For green foliage against the blue sky, a green filter will lighten the foliage and darken the sky. The wrong filter is worse than no filter. A yellow filter might worsen the subject's complexion in a portrait, while a green one might help to hide blemishes, freckles, etc. An orange filter will give dramatic sky and cloud shots, but will often spoil a portrait by making the lips too light.

Leica lenses, and others with good contrast, have minimal flare and dispersion, so that as little stray light as possible gets infused into shadow areas. That's often good, but it's a different issue from manipulating contrast with filters.

There was a time when films were deficient in sensitivity to the longer wavelengths, and a light yellow filter such as a Kodak K1 helped give the film a more uniform spectral response. Today's films generally have a more uniform response, making the habitual use of a light yellow filter largely unnecessary.

A good quality filter won't perceptibly degrade image quality. Leica, B+W, etc., are fine.

The best thing is to use a specific filter for a specific purpose, and not to use a colored filter just out of habit.

Hope this helps.

Best Wishes,

-- Bob Fleischman (RFXMAIL@prodigy.net), March 06, 2001.

I found that most of the time the traditional medium-yellow filter has a minimal effect. For outdoor scenes with blue skies and white clouds an orange filter produces a rendition closer to reality. A polarizer works just as well, but is sensitive to relative angle to the sun whereas the orange filter isn't. For portraiture outdoors a light green filter (I forgot the Wratten designation) works well.

-- Jay (infinitydt@aol.com), March 07, 2001.

I have found that Ilford Delta films do a better job of contrasting white and pale blue than other B&W films, even when no filter is used. Also, for a general purpose contrast enhancing filter, I prefer yellow-green as it helps not only with respect to sky/clouds, but also with foliage/non-foliage. Of course, for the really dramatic skies, a #25 red filter is hard to beat.

-- Dan Brown (brpatent@swbell.net), March 07, 2001.

Thanks for the responses! I took off the yellow filter and put back the UV for the time being. I've also been experimenting overexposing film 2/3's of a stop instead of 1/3 (eg 400 rated @ 250, instead of 320, as I usually do). This has helped fill in the shadow areas more to my liking and improved contrrast at the same time.

I think one of the reasons I liked the results from using the yellow filter so much is for some group portraits I've doing a lot of. The 'subjects' have a wide range of complexions ranging from light to dark, with the darker subjects having quite a bit of yellow in their complexions. Using the yellow filter made metering for the whole group a more managable task. Does anyone have any suggestions how to accomplish this w/out the yellow filter?

-- KL Prager (www.pragerproperties@worldnet.att.net), March 08, 2001.

I use either the tiffen yellow 12 or B+W 023(both med yellow filters). I use them almost always, and like the effect (almost)regardless of situation. I haven't conducted tests between unfiltered and filtered, but tried shooting without the filter, and just plain didn't like it. I was told once that yellow filters should be used with panchromatic film, but I'm not sure that command was well founded. I have shot portraits with the tiffen8, tiffen12, and B+W023. All three were very close, and I keep a yellow on at all times. I don't think I'm really missing out on anything. Hope this doesn't send anyone into an incredible dilemma regarding filters. This is just what works for me + my nikons. The contrast of Leica lenses is purported to be quite good, so I understand the filterless approach.

-- Mike DeVoe (karma77@att.net), March 12, 2001.