Not just any film

One of the things that really throws people about very, very old films is that there is something 'off' about the shading. Everybody knows what black and white photos look like, but Nosferatu (1922), for example, has a very different contrast and gray-balance than Casablanca (1942). The sky in old silents is always diffuse and cloudy, faces are always white, lips either invisible or nearly black. Guessing hair and clothing color is nearly impossible.

This is not actually a problem with the quality of the film stock, believe it or not. Film is film; the sharpness issues you run into with analog TV (405/525/625 lines of resolution) or digital (SD vs HD, and the various kinds of encoding) do not exist with old stock versus new stock. Many of the transfers you've seen are appalling, but this is because the film is generally filthy, sometimes in poor condition, and the material often in the public domain. Unless someone is making a historic collector's edition, they generally don't bother coughing up the extra cash to clean up the original print or make a new wetgate transfer for DVD -- they just use whatever was lying around from when someone put it out on VHS twenty years ago. Then they pitch it through the MPEG encoder without changing the default settings.

If you're really lucky, the crap transfer will then be uploaded to YouTube, where none of it will much matter anyway, because full-motion video is exactly the thing Flash was invented not to do in the first place. Two wrongs don't make a right, but three or four of them do make an obfuscating mess, a principle which forms the basis of much of the modern public relations industry.

In any event, the reason the contrast looks so wacky is because early monochrome film and late monochrome film are sensitive to different kinds of light. If you watch old TV or movies, you sometimes see a scene of a photographer developing and printing his photos in a darkroom illuminated by deep ruby red lamps. Nobody does this anymore -- someday it'll be one of those things your grandchildren ask you puzzled questions about, like "Why is his phone attached to the wall?", and "What do they mean, snow on the TV?" It's unnecessary, for starters, as most film goes through a lab these days where it's developed in the interior of a large machine where everything is black, and printed via inkjet onto specially-prepped photo paper.

And for another thing, it wouldn't work anymore. Red light wrecks modern film the same as any other color. The reason it didn't wreck film before -- and the reason things like lips look black in old movies -- is because early film was orthochromatic. "Ortho-" means something like 'right, correct', or in this case, 'specific'; "-chromatic" is obviously referring to color. The unadulterated silver halide suspension used on early photographic film was only sensitive to one color of light, in this case a very blue-skewed cyan. No matter how much light you poured onto the scene as a whole, only the cyan component counted. Red light meant bupkis, so it didn't matter how many red lamps you had in your darkroom, they wouldn't screw up your exposure as you pulled the film out of the camera, and bathed it in assorted carcinogens.

Cameras work on reflected light. In this scheme, colors are thought of as being mixed from red, blue, and green; if something looks blue, that means it's reflecting all the blue light that falls on it back at you, and absorbing all the red and green light that hits it. So if your film is only sensitive to blue light, having something that reflects 100% blue registers as 100% bright -- bright saturated blue looks the same as white. On the other hand, having something that's 100% red registers as 0% bright, since it's absorbing all of the blue light that the camera would need to pick it up.

Newer film, even black and white film, is panchromatic, "pan-" meaning "all, everything". Panchromatic film reacts to the total intensity of the light falling on it. (Roughly. Chemically, sensitizing the film to reds and greens also made it extra-sensitive to blue and UV, so lens filters were needed on the cameras -- but I'm getting ahead of myself again.) Color doesn't matter to panchromatic film, but the brightness of the image does. When you do television, a color TV signal carries the RGB part separately from the brightness (called luminance) part; you can watch color programming on a black and white set because the brightness of the image is preserved even when the color information is discarded. Similarly, when you film a color scene on black and white film, the color information is discarded but the film registers how bright things are.

The difference is quite striking when you see a comparison between the two methods. Both are reasonably easy to simulate in Photoshop (or, if you are cheap/broke like I am, GIMP). Panchromatic monochrome is roughly equivalent to taking a color image and desaturating it 100%; orthochromatic monochrome is roughly equivalent to taking a color image, decomposing it into separate RGB channels, discarding the red and mixing the blue with the green at a low opacity.

I have here a photo of me, conveniently taken by a photographer out in Somerville.

Full-color original

You'll note the range of color -- the dress is a vivid blue, while the bracelets are brass, the necklace is gold, and the backlight on my hair is orange. Me personally, I am the color of a human who hates the sun and bathes in sunscreen, and my hair is copper red. I was wearing pink/copper/gold eyeshadow with black liner and mascara, and nude lipstick with a gold gloss.

I loaded it into GIMP and ran the desaturate filter, which removes the color information while preserving the luma channel. This is approximately what the photo would look like on a modern panchromatic film.

Panchromatic monochrome

You'll see that the dress, which is very colorful but only medium bright, has come out a sort of middling shade of gray, whereas the me stuffed into it is still quite strikingly pale. The halo around my hair is still distinct and retains its high contrast with the black drape in the background, even though it's no longer sunset orange.

Next, I took the same original photo in GIMP, and decomposed it into red, green, and blue channels. I tossed the red, and combined the blue at 100% opacity with green at 25% opacity. This is approximately what the photo would look like on orthochromatic stock sensitive to cyan/blue.

Orthochromatic monochrome

You'll see that the dress suddenly looks very bright, and I look a little bit darker. This is because people tend to be on the pink side, what with having blood and all. In the panchromatic plate, the red light reflected from my skin counts when toting up the brightness; in the ortho plate, the red light is simply discarded, so I'm dimmer by whatever amount the red was contributing before. The necklace, the bangles, and the backlight on my hair have almost vanished, visible only dimly where there is a green component to the light they reflect. (RGB math doesn't work like fingerpaints; with reflected light, red + green = yellow.) My hair, which is bright titian to begin with, comes out looking nearly black; the eyeshadow just under my eyebrow came out much brighter in contrast, since it was white/sheer mica that reflected all colors equally, and with the loss of the red channel the tone of my skin no longer drowns it out.

This is especially necessary to keep in mind if you plan on doing costuming or makeup based on the makeup in old silent films. Flapper makeup will not look "right" in person when done in color if you're comparing it to silent film stills, or studio publicity photos of the time. What you need to do is look up fashion plates and advertisements to get the popular colors. Color film technically existed but was basically never used; ads used illustrations or hand-tinted photos that gave approximately the right hues, especially if they were actually trying to sell makeup.

Comments

  1. "People" aren't on the pink side. Some white people are. Also "the color of a human who hates the sun and bathes in sunscreen" can range considerably. I've been reading your archives backwards and really enjoying your writing, but this threw me right out of your post. It's very othering, as though pale white people are the only kind of real people who exist in the world.

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    Replies
    1. I'm sorry you feel that way. Wasn't the intent.

      People are in fact on the pink side; it comes from having blood, which so far as I am aware, all people do. Even people with very dark skin over most of their bodies can have lighter patches, such as their palms, which are equally interesting to white-balance. Such was in fact demonstrated by a fellow with extremely dark skin who came in to speak to my media production class, and proceeded to white-balance the camcorder on the palm of his hand.

      And I am the color of a human being who hates the sun and bathes in sunscreen. I am a human being, I hate the sun, and I bathe in sunscreen, and I am this color. I didn't say YOU were this color when you did that, but I certainly am.

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