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Pushing Film Q: If you are in a low light situation (indoors, sports events, concerts, etc) and there is not enough light to get a decent exposure, even with a wide open aperture, you don't have a tripod and can't use your flash, what can you do? a). Call it a day. b). Call a friend to quickly bring you faster film. c). Consider pushing your film. "C" is probably the best answer (though sometimes "a" might be tempting). Pushing is a term used to describe the process of increasing the rating of the film during shooting and then overdeveloping it. For example, if you have 400 ISO film loaded but that isn't enough, you can change the ISO to 800 and increase the development time. How much you increase the time depends on the type of film. You can "rate" your film higher than the recommended ISO by one stop, or even two stops (more than this will lead to great loss of image quality). In effect, you are underexposing your film because the film itself has not changed, but you are compensating for that underexposure by overdeveloping it. As we know, overdeveloping leads to increased contrast, and increased grain. Also, there will be less detail in the shadow areas, because it is the exposure that is having the biggest impact there, rather than the development. In general, increase the normal development time 25-50% for a one stop push, and for a 2 stop push double the development time. (TMax films will need less increase in development times). You can also push film by using developer at a higher concentration, or a higher temperature. Because there are so many variables it is best to test. For example... at the beginning or end of the roll take some shots that are considered a test, like general atmosphere shots, (remember which end it is) then "snip" that strip off and develop it first and hold the rest. After evaluating the test, process the rest of the film. This is called a "snip" test. If you have lots of film shoot one whole roll that can be used for development tests and hold the rest until you've evaluated the results. A most amazing resource on film processing with
information on chemicals, times etc.: When possible use a higher speed film rather than push processing!
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