I made a wrong assumption (re: ISO and exposure) :)

[dots]

Just trying to find the thread were i wrote i thought if you meter for middle grey, that stays the same regardless of ISO. Incorrect..

Digital cameras increase ISO speed by ... moving a given exposure to a lighter zone. An exposure that would fall in Zone 9 at ISO100, would fall in Zone 8 at ISO200, Zone 7 at ISO400.

Tonal quality and dynamic range in digital cameras

 

[dots]

..twistin my melon, man!

 

[unpopular]

... isn't that just how it would work? If Zone V is 1/100 f/4 at ISO 100, wouldn't it be Zone VI at ISO 200 provided that you did not compensate, regardless if it's digital or not?!

Or are you complaining about how digital cameras increase ISO by bumping gain?

 

[Helen B]

Are you getting mixed up between Zone System zones and the 'exposure zones' that Norman Koren is referring to in his Table 1 on the same page. Apart from running in opposite directions (ZS zones get lighter as the number rises, NK's get darker as the number rises) they are referring to different concepts. I think that if you re-read NK's article, and forget about ZS zones, it will all become clear and not contradictory.

Best,
Helen

 

[dots]

Yes! Heck Norm! Stop it!!

 

[unpopular]

Damnit! You people need to stop getting me confused. Without Helen, I'd start to question everything I thought I knew.