Pull or Push - just checking

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Sorry for my mind being in a muddle.... I always expose 2 quickloads identically of each scene in case of disasters. In this case I have had one set developed and they are a little too light. I assume I ask the lab to pull process by x stops when I have the second set developed because I have given more light to the film than I should have.

Thanks

Dave

-- David Tolcher (davidjt@btinternet.com), April 06, 2002

Answers

That's correct. But, you will lose some contrast in pull process.

-- Mahmut Gunes (mgunes@turk.net), April 06, 2002.

Your assumption is correct IF you're shooting transparencies. IF not, it is backwards.

-- Kevin Crisp (KRCrisp@aol.com), April 06, 2002.

Dave:

I use a similar technique... but if you do this with transparency film, you should try to be on the under, not over exposed range of exposure. Pulling generally has less success than pushing. For example, with Provia 100F you can only pull 1/2, maybe 1 stop at most. You can easily push 1 or 2 stops.

-- Glenn C. Kroeger (gkroeger@trinity.edu), April 06, 2002.


(Again, assuming transparency film)..........another way to approach this is to shoot the original (qty-2) chromes for intended development at +1/2. Then if the first (tranny developed) is too light, you can process the second at N without experiencing the significant contrast loss due to pulling the film. This of course assumes that the scene can withstand the added contrast due to pushing.

so for example with Velvia, I shoot the scene at ASA64 (this assumes an actual ASA of 40) and develop at +1/2. This gives me a latitude of 1 and 1/2stops (N to +1 and 1/2) to account for exposure errors on the second. (my personal feeling is that Velvia goes too (wierdly) warm at +2)

Pulling film is a very useful tool, but comes with its own set of problems. In my experience, Velvia pulls nicely to -1, but with a very significant contrast loss, and a shift to magenta. Of course, with the reduction of overall contrast comes the cooresponding reduction in local contrast. Many times, (at -1) once the overall contrast is controlled, the reduction in local contrast often leaves the image lifeless and dull. (read - not useable). You can cc green to account for the magenta shift.

I use Velvia as an example.....any film should be personally tested to account for taste.

-- George Stocking (gwrhino@earthlink.net), April 12, 2002.


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