The only difference is the time it takes to develop. I mentioned that to my prof too, and he said "oh, don't worry about it. it won't make much difference, we'll do yours the same as everyone else's."
I told my photofriend and he said "man, that's what I hate about that prof. He gets fuzzy on the technical stuff and thinks it's not as important. Do it with the right times that I sent to you."
We develop in two days, and we'll be doing it as a small group, so my times will be off the whole time and my prof will know if I'm doing things differently.
Who should I trust, my friend or my prof?