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Some questions about B&W


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#1 Jayson Crothers

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Posted 23 September 2007 - 11:48 PM

I'm prepping a B&W feature and I keep running into wildly different opinions on certain questions.

I've read that "Schindler's List" ran into issues with static discharge in the mags due to the silver content in B&W emulsions that resulted in lines and dots appearing on the film. The only practical solution sounded like damp sponges placed inside the camera body, but even that sounds questionable to me. How much of an issue is this really (is it climate based or just inherent to shooting on B&W)?

Kaminski also mentioned (although a bit vaguely) that he treated 5222 (200 asa) as though it was a 100 asa stock; it's not clear if he simply over-exposing in his lighting or if he was actually rating the stock at 100 asa and then printing down one stop. How does over-exposing/printing down and under-exposing/printing up differ in B&W versus color?

I was able to shoot some tests (though they were very abbreviated) and I was surprised by how grainy 5222 is; I expected some grain, but it seemed excessive (especially when compared to something like "Schindler's List") - my printer lights were quite high (low to mid 40's). Any thoughts or advice on ways to minimize grain (I know that sounds like a silly question, but it can't hurt to ask)?

Thanks everyone!
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#2 David Mullen ASC

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Posted 24 September 2007 - 12:37 AM

Kaminski didn't really overexpose 5222 in order to reduce grain -- what he actually meant was that he found that, in order to have an image with a full tonal range, (Caucasian) faces often had to be one-stop overexposed, i.e. exposed for a lighter grey zone to create a highlight, or else they looked muddy and grey. He discovered after the first few dailies that the faces had to look "hotter" to create more snap to the image, so he started overexposing them by one-stop. Now one could do this either by just rating the stock one-stop slower and lighting for more contrast, or by rating the stock normally but making the key light one-stop brighter than normal.

Now in terms of printer lights, his base rating may have also been a little lower in order to print at a higher light, but that would mainly be to get a better black in the print, not to reduce grain.

B&W film doesn't behave the same way as color negative in terms of greater overexposure equals less grain, since exposure = grain in b&w, i.e. the image itself is made up of silver grains. As if with color film, you need enough exposure to fill-in the gaps between the large grains with the smaller, less sensitive grains. But overexposing a lot and printing down doesn't do a lot to reduce the appearance of graininess with b&w neg.

There really isn't a good solution to reducing the grain of '22 -- I find that it is better to push '31 (Plus-X) one-stop instead. The plus side of b&w neg is that it responds well to pushing, which tends to increase contrast more than increase graininess a lot.

The graininess of '22 is the main reason people these days would rather shoot a 500T color negative and remove the color in post because it is both less grainy and faster in speed.
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#3 Jon Kukla

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Posted 24 September 2007 - 12:45 AM

Static can occur for several reasons, but the most common one usually is atmospheric conditions - specifically dry air. I wouldn't be surprised if the conditions of filming in Poland made that more probable.

As far as the exposing goes, black and white is a different beast from color in that the baths are really as strictly standardized as with the ECN process, so different labs will often have slightly different gammas upon testing (and sometimes can even be set to particular gammas on request). Of course there are also far fewer labs developing b/w now compared to 1992/1993...

There's no real difference in what you're asking about the 100 ASA - if you rate the 5222 at 100, then by definition you're overexposing a stop from the Kodak-recommended EI (assuming tungsten light). The overexposure should also help to counteract the graininess to a degree, but '22 is well-known for being a fairly grainy stock by nature, which is why many cinematographers in recent years have opted to shoot their b/w with modern color stocks and desaturate in post in order to avoid the grain. The 5231 has much finer grain, but you of course gain that at the cost of film speed. (If you're able to rate at 100, though, this might not be too difficult.)
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#4 Jayson Crothers

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Posted 09 October 2007 - 08:50 PM

I wasn't clear in my question - I wasn't clear if he actually rated the stock at 100 asa (hence shooting a neg that's a full stop overexposed and then printing down) or if he was rating it at 200 asa but when it came to lighting only people and faces he was "over-lighting" as though it were a slower asa.

Between David's explanation, re-reading the article, and a few other sources, it sounds like he rated at 200 asa and then just pumped up the light on faces.
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#5 John Sprung

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Posted 10 October 2007 - 12:27 PM

Static is rarely a problem any more, and the silver halide in B&W is no different than it is in color. There's no metallic silver present until after it's developed. If you have exceptionally dry air, run a humidifier on the set, or just spritz some water around with a plant mister. Add a little Downy fabric softener to the water you spray around, it helps to drain static better than just plain water. Try 4:1 to 10:1 mixtures.




-- J.S.
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#6 Dirk DeJonghe

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Posted 10 October 2007 - 01:54 PM

I have found that the speed of Kodak (and other B&W) negatives needs to be tested before production starts. In the majority of cases we find 5222 rated at about 100 giving good shadow details up to about 3.5 stops below keylight.

I did some testing with sensitometric strips mutually exchanged with Kodak Chalons CTP and they came to the same conclusion.
Grain increases with negative density in B&W, opposite of what is happening in color negative.

If you really want to learn B&W read Ansel Adams 'The negative' it is still the reference for serious B&W work.
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