How much can you push pull HP5+?

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After finally completing a good part of my film testing, I'm starting to determine what I have to do to push/pull HP5+ (my main film). Adams said in 'The Negative' that 'modern' day films (1985ish, from the publication date of the book) can really only be pushed and pulled one zone - anything after that is questionable.

Does this still hold today? Reason I ask is that I was shooting some early morning shots yesterday at Lake O'Hara (if anyone is near the Alberta/BC border off the #1, try and get on the bus to make it to the lake - it's amazing), and I had a 9 zone difference between some shadow detail and snow on the high peaks in the sunlight. I would have liked to pull the film two zones, but didn't think that would work - I pulled a single zone, and got a little bit of detail, but not as much as I would like. Even had I been able to pull two zones, I still wouldn't have got the detail I wanted, but it would have been better.

Opinions please!

-- Ken Miller (andawyr@hotmail.com), August 30, 2001

Answers

It all depends on the gamma you develop your negs for. With a compensating developer it would not have been a problem to record a 9 zone contrast range if you whould have chosen a low gamma. For example Rodinal 1:100 would have easily done the job. In fact with a high speed film such as HP5 you can record an even larger range, which is commonly used in high contrast indoor scenes.

-- Volker Schier (Volker.Schier@fen-net.de), August 30, 2001.

I often push one or pull two with HP5+, but I think more than that in either direction causes more problems than it solves.

-- John Hicks (jbh@magicnet.net), August 30, 2001.

John, what developer do you use to push and pull? I'm using Ilfotec HC, which gives me very fine grain.

Thanks!

-- Ken Miller (andawyr@hotmail.com), August 31, 2001.


I use an assortment of developers, usually depending on format and what's mixed up or available. Rodinal 1:50, D-76H 1:1 and 1:3 and Ilfosol-S give similar curve shapes and development-change response. Ilfotec should be about the same; I tried it years ago but wandered on to something else.

My "hail mary" N-3+ is usually using D-76H 1:3 at the 1:1 development time at EI 200.

The big drawback of such a contraction is that while it dramatically reduces overall contrast, the paper expands local contrast in the midtones and often leaves the shadows and highlights somewhat too low in local contrast.

-- John Hicks (jbh@magicnet.net), September 01, 2001.


I would also consider flashing the film (gray card, out of focus, etc etc) which is supposed to boost your shadow detail in such difficult situations (Adams proposed that solution also). A two bath extreme compensating developer could also help... You could also try helping your high contrast negatives (if they end up like that) by masking them (unsharp, for better results) when printing.

-- George Papantoniou (papanton@hol.gr), September 01, 2001.


'Pushing' film usually refers to under-exposing/over-developing to get more 'speed.' With HP5+ you can 'push' it nearly to lith film, if you want to. But what I think you are talking about is 'expansion/contraction' of the 'subject brightness range,' often erroneously referred to as 'contrast.' I have managed to develop HP- 5+ to a +3 ZONE expansion as measured on a densitometer, but have NEVER had to do this for a photograph. Once in a great while I have had to contract a negative by one ZONE, and even more rarely, by two. The local contrast remains perfect with a single zone +/- and suffers only mildly with 2. BUT I use PMK exclusively, which is extremely well suited to ZONE manipulation. Get Gordon Hutching's Book of Pyro. All the times for ZONE system use are there, and are surprisingly close to what I found with my tests.

-- Michael Fraser (mdfraser@earthlink.net), September 24, 2001.

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