pushing film iso?

[MHB]

Two part question

1) I heard someone on a youtube video say if you push your iso you should let your lab know so they can process it correctly. Is that true?

2) If you push 400 to say...800 will you get the grain you would usually see in 800 or will it just give you the faster speed?

 

[Mark Upfield]

You should be able to test this yourself... Zoom into 200% and check the pixels then do a noise reduction and re sharpen if needed

 

[snowbear]

Yes, pushing the film will require a change to the development time so the lab needs to know, otherwise your shots will look underexposed.

Pushing can increase the grain, but one stop should be OK if the photo is not too dark.

You should be able to test this yourself... Zoom into 200% and check the pixels then do a noise reduction and re sharpen if needed

. . . um, film, dude.

 

[limr]

Two part question

1) I heard someone on a youtube video say if you push your iso you should let your lab know so they can process it correctly. Is that true?

2) If you push 400 to say...800 will you get the grain you would usually see in 800 or will it just give you the faster speed?

1) Yes. That's how pushing works - it's a longer development time. You should also probably ask your lab first to make sure they will.

2) The images will generally be grainier. How much grainier may depend on the film and exposure.

TriX (ISO 400) pushed to 1600:

Street food by limrodrigues, on Flickr

 

[Mark Upfield]

Sorry guys fully mis read... Yes is the answer then

 

[webestang64]

YES.....let your lab know what film speed you shot your film at. It is possible to push film up to 3 stops and still have very acceptable results.

Also pushing film from 400 to 800 will not result in 800 speed grain. If you are pushing BW films ask your lab if they have special processing using Kodak X-Tol. X-Tol will reduce the film base down and keep grain tight. I've used X-Tol to push T-Max 3200 to 25000 and still have highlight and shadow detail.

 

[gsgary]

When pushing you are underexposing you don't get more speed you just increase the contrast

 

[cgw]

1) It's 2015 and you can't assume your lab runs a tight enough C-41 line to do a a consistent 1-2 stop push. Maybe it does. If not, you're probably safer shooting Portra 400 at ISO800 since its latitude is arguably more dependable than most labs' ability to handle extra processing time.

2)Largely dependent on the film,which you don't specify. Materials like Fuji Superia 800 rated at ISO640 and kept clear of underexposure often look better than ISO 400 Fuji Superia pushed. Again, you're at the mercy of your lab's--or any labs'--ability to push process accurately.

3)No clue whether you're talking C-41 or b&w film. If you're really serious about this, tell us what you're shooting and what type of film you plan on shooting.

 

[gsgary]

1) It's 2015 and you can't assume your lab runs a tight enough C-41 line to do a a consistent 1-2 stop push. Maybe it does. If not, you're probably safer shooting Portra 400 at ISO800 since its latitude is arguably more dependable than most labs' ability to handle extra processing time.

2)Largely dependent on the film,which you don't specify. Materials like Fuji Superia 800 rated at ISO640 and kept clear of underexposure often look better than ISO 400 Fuji Superia pushed. Again, you're at the mercy of your lab's--or any labs'--ability to push process accurately.

3)No clue whether you're talking C-41 or b&w film. If you're really serious about this, tell us what you're shooting and what type of film you plan on shooting.

The lab I use for my colour development is probably one of the best in Europe and is within walking distance from my home
UK Film Lab Professional Film Processing and Scanning