A question about developing from an amateur who knows absolutely nothing about darkroom work.
Sometimes I'm in the middle of a roll and decide that I would rather have higher speed film in my camera. I don't do any of my own processing - I simply drop the film off and if I pushed the film then I tell them that I did so. Now say I have a roll of Delta 400 in my camera and shoot exposures 1-18 at 400 iso. Then I find myself engulfed in total darkness and decide to push the film a stop for exposures 19-36. Obviously, if I just get it developed half of the prints will be either over or under exposed depending on whether I instruct the shop to develop at 400 or 800. No problem. But if I later decide to get enlargements for, say exposures 8 and 30, is there any problem with just telling them to expose 8 at 400 and to push 30 by one stop.
Put another way, and hopefully in much simpler terms, when the negatives are being "rinsed" does it matter whether you've pushed the film. Is over/underexposure - as in pushing and pulling - merely something that matters for the purposes of printmaking and has absolutely no effect on how you treat the negatives?
As I said, I know absolutely nothing about film processing, so any help would be greatly appreciated.
cheers,
Lucas.