zone system

[drew2143]

I know this really isn't a digital photograhy related question but i thought i'd ask it anyway. Is changing the development time in black and white film from "n" to "n+1" the same as changing the exposure from "n" to "n+1". The reason i'm asking is because i'm trying to learn the zone system and am a little unsure about it. Theoretically this would cause the exposure to change from zone V to zone VI. But would it have the same effect in development and exposure? Thanks
andrew

[Franglais]

I know this really isn't a digital photograhy related question but i thought i'd ask it anyway. Is changing the development time in black and white film from "n" to "n+1" the same as changing the exposure from "n" to "n+1". The reason i'm asking is because i'm trying to learn the zone system and am a little unsure about it. Theoretically this would cause the exposure to change from zone V to zone VI. But would it have the same effect in development and exposure? Thanks
andrew

Increasing the development time of a black and white film increases the density but it also increases the contrast. You use this technique when faced with a low-contrast subject so that the tones are spread out over all the zones rather than just part of them. The increase in film speed is incidental.

If you change the exposure from "n" to "n+1" then you're just moving all the zones up one, you're not changing the contrast. Black will go grey and highlights will start to wash out.

Charles

[another view]

I know this really isn't a digital photograhy related question but i thought i'd ask it anyway.

No problemo - this is the place for it! Lots of film shooters here.

[drew2143]

Thanks for the help, but i'm still a little confused. Correct me if i'm wrong, charles said changing the development time effects contrast and density. Which would mean shadows and highlights would be effected. So changing exposure time would just make the shadows darker and lights lighter? The actual contrast in the photo would not be effected? So you expose for your shadows and develop for the contrast? thanks
andrew

[Franglais]

Thanks for the help, but i'm still a little confused. Correct me if i'm wrong, charles said changing the development time effects contrast and density. Which would mean shadows and highlights would be effected. So changing exposure time would just make the shadows darker and lights lighter? The actual contrast in the photo would not be effected? So you expose for your shadows and develop for the contrast? thanks
andrew

Reducing exposure makes the shadows darker and the highlights darker. Increasing exposure makes the shadows lighter and the highlights lighter. It doesn't affect the contrast.

Increasing development makes the shadows a bit lighter and the highlights a lot lighter. In other words it increases the contrast. A Zone 2 value stays at Zone 2 but a Zone 7 value becomes Zone 8 etc.

When you expose you have to ensure that you have recorded the detail you need in the shadows (because if you haven't then no amount of development is going to put it there). You adjust the development time to ensure that your highlights have just the right density to be placed at zone 8 on your perfect negative that will print straight onto grade 2 paper.

Charles

[92135011]

Be very careful with what film you use though....
I have this one magazine that tested film of various brands.
Some films already have a very steep exposure curves (already high contrast) at their recommended ISO. So pushing the film and increasing contrast could mean bad news, especially if you are shooting people. Problem is also that different developers have different effects on the exposure curves as well.

Matter of taste. Matter of experience.
Could you tell us the film and developer you use?
I could look up what this guy in the magazine did and you could possibly try it out to see if it works out for you. Just a suggestion