how does iso work on ZI ?

[absolute]

hi ~ everybody

I'm new to film, just owned ZI for 2 months,

I don't understand how does the ISO work on film camera..

let's say the film is ISO 400, then it should work as it is,

what happen if I use ISO 400 film and set the camera to ISO 100 ?

This question came up because I was about to use Kodak VC 160,

I wonder if I should set the camera to ISO 100 or 200, and how exactly the ISO dial works ?

Thank you!

 

[FA Limited]

the iso dial controls the meter readings
by setting the ISO to 100 or 200 with ISO 400 film, you would be overexposing +2 or +1 EV

 

[Roger Hicks]

The ZI has unmarked 1/3 stop dots: 100 (125, 160) 200 (250, 320) 400 (500, 650) 800...

With colour neg films, under-exposure (higher ISO) = bigger grain as well as empty shadows, but over-exposure (lower ISO) = finer grain BUT lower sharpness.

True ISO speeds of B+W films vary with the developer -- an 'ISO 400' film may go below 250 in a fine-grain developer and approach 800 in something like Ilford DD-X -- and besides, you may find that you like the results better with a little more or (rarely) a little less exposure. That's before you start 'pushing', i.e. over-developing in a search for more speed. You may find this useful in understanding ISO speeds: http://www.rogerandfrances.com/subscription/ps iso speeds.html

Cheers,

R.

 

[mfogiel]

You put the film in the camera. Then you decide how do you want to expose this film, and you set the ISO value in the little window inside the speed wheel to that value. In case of your Portra 160 film, I would suggest you shoot at ISO 100. One more complication: if you shoot a scene against a bright background, you can point the camera at the subject alone, and press the little silver button at the back of the camera - this reading will be constant for 30 seconds, during which you can recompose and take your photograph.