Quote Originally Posted by kbrede View Post
The reading I've done in terms of film exposure is geared toward B&W. Are there any differences in use of the zone system or exposure in general that I should know about for Portra?
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Unless you are printing onto paper, you don't need to use filters (maybe the UV is worth it if you are really high).

As for exposure, I've done quite a lot of testing and the dynamic range is immense in the highlights, up to +14 stops

I exposure Portra for the shadows and let the highlights go. Portra 400 place the darkest shadow with detail at -3, Portra 160 I would expose the shadows at -2 stops. The advise to shoot at half box speed isn't a bad one as long as you know why :-)

Because of this, my Portra 160 landscape exposures very often end up as exactly the same as my Velvia exposures... that tells you a lot about exposure rating..

Portra 400 copes OK at box speed because it has more scope in the shadows..

Here's a portra 400 shot..

http://static.timparkin.co.uk/static...ra-test-pp.jpg

This was reading from 4EV to 19EV and nothing is blown or blocked

here's another scene with the same dynamic range where I've opened up the shadows and burned the highlights to show what real data is there..

http://static.timparkin.co.uk/static...amic-range.jpg

I tend to only use a grad if I want to reduce the grain or get smoother colour when I know I'm going to burn in skies a lot.. Even then I tend to only use a soft grad instead of a hard one - completely optional for most work though.

Tim

p.s. As a good example of how much dynamic range it has - I was shooting a job on my new GX617 where you have to lock the cable release wide open to use the ground glass. I forgot to close the shutter before loading the film and hence my first exposure got about 30 seconds at f/5.6 instead of 1/15 at f/16. Now most people would say 'yep, that's blown out now!!'. I scanned it for a laugh as I thought I could see something - amazingly the scene was all there!! It was grainy as hell but it was there never the less!! That's a 12 stop overexposure!!