Pushing film?

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WHAT! pray tell does pushing film mean? Let's say I am using 100ASA film. Under what circumstances would you push the film and what are the effects of doing so?

-- (anniejim@dellnet.com), September 23, 2000

Answers

I will offer the general answer, and let others give specific uses and recommendations: Pushing film means exposing and processing it as if it were more light sensitive than its ISO rating would indicate, which in many films is not that precise anyway. Pushing film means underexposing it from slightly to excessively, and compensating by extending the development, usually by time.

-- Tony Rowlett (rowlett@alaska.net), September 23, 2000.

Primarily film is pushed to get a more useable shutter speed or greater depth of field under difficult lighting conditions. Some times film is pushed, or pulled, to aquire a certain "look". I usually carry just Provia F for my colour work. In reasonable lighting I use the film at its rated speed (100) but as the light gets dimmer I rate the film at 200 (one stop push) or 400 (two stop push) depending on the lighting and subject motion. I just shot off a roll in my son's dance class where I pushed the film one stop to 200. I ended up exposing at 1/60 at f2 which was just fine as I was hoping for a little blur and much better than the 1/30 I would have had at the rated speed.

Cheers

-- John Collier (jbcollier@home.com), September 23, 2000.


All that John said is true. The only thing left out is that after you shoot your film at that higher ISO, you must compensate during the development stage... otherwise all you will have is underexposed film. Slide film has lower tolerance for erroneous exposure, so it is critical to let the lab know what ISO the film was shot, so they can adjust the processing time.

Also, there is no free lunch. It is best to have the right film, but if not pushing is better than no photos. Some reports show that some films are actually better pushed than the next fastest film... so pushing is not just a possibility, but better than the result from faster film. This is true of slide film... faster print films are excellant these days.

Pushing can lead to black shadows with no detail and higher contrast and grain. If this is something you think you might have to do, you should burn some film and take notes. Everyone has a different level of acceptance for image quality, so you should know the outcome before you need to do it in an important situation.

-- Al Smith (smith58@msn.com), September 23, 2000.


Others have implied, but not stated explicitly, that there's really no such thing as increasing film speed by pushing--what you get is increased contrast. This *might* lift some brighter shadows into a very slightly higher range (a look at the appropriate curves show that this lift is almost negligible--most of the change occurs in the highlights, where you don't need or, especially, want it), but nothing is added to the shadows that wasn't there before "pushing". If you are doing a lot of digital work, as many people are, you'll find that "pushed" negs are harder to scan and give worse results in general, but that properly scanning and manipulating scans of underexposed non-pushed film in general will often give you better results.

-- Michael Darnton (mdarnton@hotmail.com), September 30, 2000.

I think Michael's comments about the difficulties of scanning pushed film apply equally well to printing. Extending the development time, in an effort to increase negative density, leads to blocked up highlights which reduce the printability of the negative. Pushing Provia 100 leads to higher contrast and inky-black shadows.

So, what of Kodak's claim that T-Max films are easily pushed, for example in T-Max developer? I think one gets away with it a little better, with T-Max, because of its very good shadow speed. I can readily see that T-Max really does have more shadow detail than, say, FP-4, to name one where I've made this comparison. Kodak even recommends a normal development time when "pushing" (underexposing) T- Max by one stop. Even so, you don't get as much shadow detail as if you had not pushed. But the loss is minimal at one stop under. Only thing is, T-Max tends to be a bit flat, IMHO, in many developers, including T-Max developer.

Regards,

-- Bob Fleischman (RFXMAIL@juno.com), November 12, 2000.



I actually just "pushed" some film for the first time recently. I was completely surprised (and pleased) with the results. I was using Kodak Tri-X 400 and pushed it to 3200 to take pictures in a dimly lit basement. I actually thought that I might be pushing it too far to develop useable prints, but it turned out great. Also, I am not a stickler for development temps and times (as I learn more I will be!), but my film still came out great. I think this just goes to show that experimentation can work out great for us amateurs. I would suggest playing around with pushing and pulling film. Like the others said, you can get some great unique results!

-- Aaron Stein (asvolley@aol.com), December 22, 2000.

I can agree with the above statements, but I find that shooting Tri-X at 400 is already a push. It is really 200 to 320. What do you think?

Art

-- Art (AKarr90975@aol.com), December 22, 2000.


Does anyone know about specific development times? If you do 400-- >3200, do you develop it 200% as long as you usually would, or 150% Thanks

-- Kirsten Ware (cursedin@yahoo.com), March 31, 2002.

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