The Film Scale
Okay, the next is when we look at the film scale. So the film scale tells us the relative way in which that contrast is developed. Is it a fast accelerating high contrast? Is it a lower contrast? And we have these two points: the shoulder and the toe. These two things are very important when we're dealing with any kind of film. Doesn't matter if you're working with Chrome, E6 film, C41 color negative film. They all have a toe and a shoulder. The toe, and down here is basically where no exposure is happening. Exposure then starts to build up. We're gonna talk about the zone system in a second, and what we're looking for is a doubling in light. That creates a stop. Every time the light doubles, we get an increase in stop. The toe is basically as we're starting to come out and tone's beginning to develop, so in the black and white world we're looking at tone and texture are our two elements. We're starting to get tone and texture to come up, and then right about here is where we start to ...
render full texture, just outside that toe. Anything below there, though, we have no detail. The shoulder is at the high point. So this line here is gamma, that's our curve, when we get above the shoulder, this starts to fall off and there's so much density built up on the negativity, it was exposed to so much light, that nothing prints past the shoulder. So the world of film that's critical is between these two lines. I've got a little bit down here, but I've gotta stay out of there. If you're a digital person, this is a clipped highlight, clipped shadow. Now, the cool part about black and white film is if you think about the number of stops, the dynamic range we can work with, film actually has about 16 to 18 zones of workable data. Huge latitude. A slide film, an aggressive slide film with a lot of range, four and a half, five stops. Color negative film, 11, 12, 13, somewhere in there, so black and white film just has a huge latitude for us to be able to work with. The cool part is I get to massage all of that through my manipulation of where I place things, and the things we're talking about, metering, and then the development. But these two points become pretty critical. You will see those two points in every one of those film charts. There'll be a characteristic curve, is what it's called, so any of those data sheets, you get the characteristic curve. Now if I come in and take this film, shoulder's about the same, a little bit more aggressive slope, but not much of a toe, so I actually have a lot more, probably, shadow detail down there. When it stops, it's over. There's not a gradual transition there. Or I take that one and I have a smoother transition, so I actually have a less steep contrast, and I don't have as much toe and shoulder. So those different curves will all be in the characteristic piece, and what I'm just looking for is how steep is that line. The other thing you'll see in those curves is you'll see sometimes a dotted line above and a dotted line below, and that says they're applying different development options, and we'll talk about that in the second segment, how I can move the elements of those lines. Okay, the next thing, after we get Grain, contrast, we think about the film scale, the next thing we're gonna talk about is film speed, so this is the thing that everybody gets twitchy about.