Pushing Film

[jrgoresko]

What exactly does pushing film do? If I had a roll of 400 film that I wanted to push to 1600, would I set the ISO to 1600, even though the film is 400. Then, when I go to develop it, develop the film as though it really is 1600 film?

What are the benefits of pushing film? The more you can tell me the better. Thanks.

 

[Big Mike]

I'm sure someone more knowledgeable will come along soon but...

What does it do? It should underexpose the film. Setting the iso to 1600, with 400 film, would be pushing the film two stops. Therefore underexposing it two stops.

I don't know if there is a difference between processing it as regular 1600 or for 400 pushed two stops.

The advantage is that you can use faster shutter speeds for hand held shooting. It also brings out, or lets you see the grain in the film which some people like.

 

[jrgoresko]

Thanks. If someone can tell me whether I should develop the film at the actual film speed or the set ISO that would help. Also, can anyone post a picture of a pushed photograph, so I can see the grain effect?

 

[markc]

Check out this thread

 

[jrgoresko]

Thanks for the thread. It was informative.

So, basically the reason someone would want to push film would be to get a grainer quality that they're unable to get with film that is available for purchase or to be able to take pictures that there is not enough light to take with the true film speed in a given situation? Anything I'm missing?

 

[markc]

Thanks for the thread. It was informative.

So, basically the reason someone would want to push film would be to get a grainer quality that they're unable to get with film that is available for purchase or to be able to take pictures that there is not enough light to take with the true film speed in a given situation? Anything I'm missing?

That's about all I can think of. The main reason is to get faster film than what you have on hand or than what's available.

Oh, and now that I think about it, that shot in the other thread was probably on Ilford Delta 3200. I'd have to dig up the neg to make sure. I think the T-Max would have been grainier. I think this was T-Max. (and a bad, contrasty scan)


(bigger pic)

Here's T-Max 400 pushed to 1600.


(bigger pic)

 

[havoc]

Yeah make sure to check out the companies website for developing times when pushing film. If you are pushing the dev. time is usually longer, say 10-30% longer. Sometimes they want you to change the dillution of chemicals that you process with. When i process Tri-ax at 3200 i use straight D76 for 7 1/2 minutes as opposed to a 1:1 dillution of it for the same amount of time.

 

[ksmattfish]

On a related subject...

Recently I've been reading about Diafine 2 bath developer. It's normal ISO rating for Tri-X is 1200! Someone should check this out.

 

[havoc]

Wow, that could be interesting.

 

[Bruno]

Very interesting stuff. I don't think I've ever heard of film pushing. I'll have to look into it more.

 

[pbsdrc]

Pushing the film also increases contrast. Inversely pulling film decreases it. I usually push my film one stop for more contrast and more versitility because I have a #25 red filter on most of the time. I have found that pushing 2 stops can be a little too much contrast, but I have gotten some great pictures that way.