Overexposing pushed film?

[antiquark]

Hello,
I'm wondering what will happen if I push Tri-X 400 to 1600, but then expose it at 800. Will it give good results?

I've heard that C41 film gives good results even if overexposed a full stop, especially with respect to shadow detail. Also grain is reduced a bit.

What I actually want to do is push some film to 1600, for dim situations, but if I'm shooting in daylight, maybe I can overexpose to get better image quality.

And if the answer is yes... what will happen if I push 400 to 1600, but then expose at 400? Or is that just going too far? 🙂

Thanks,
Derek.

 

[ChrisN]

Pushing simply means underexposing (by one stop, two stops, etc), then overdeveloping to compensate for the underexposure.

It's best to shoot the whole roll with the same EI, as you have to develop the whole roll to the same developer/time/temp (unless you cut the roll).

If you expose at 400, then develop as if it had been exposed at 1600, you are simply overdeveloping, and you'll find the highlight blown out.

 

[Keith]

Only one answer for this ... Diafine! 🙂

 

[calexg]

If you ask me, there is only one answer: try it out for yourself. Experiment. Bask in the glory of not knowing what's going to happen and just do it. Developing without knowing exactly what's going to happen is hugely thrilling.

 

[Al Kaplan]

Diafine is one possibility. I wish I could still buy it here in Miami. I find that about ISO 1000 or 1200 is optimum when souping Tri-X in Diafine, but you should get printable negatives at both 400 and 1600. The old saying is that the lousier your negatives are the better the printer you'll become. Even with Diafine you'll discover an optimum expoosure for best results. At any rate a contact sheet will look a lot better if all the pix are at the same rating. Shooting some at 1600, others at 400, and you'll probably need to make two contact sheets at different exposures if you want to see what you have.

Color negative film is a whole 'nother ball game. The silver gets bleached out, leaving behind a dye image. Yes, it appears sharper and less grainy with a bit of overexposure. About one stop is optimum and two stops still gives decent results unless you want detail in the white lace on a wedding dress. A stop of underexposure and it starts looking like crap really fast! I suspect that it's rated the way it is because of those characteristics, but ISO 200 color neg should probably be called ISO 100.