Thanks everyone for their replies.
I think my initial problem was not understanding how to read the characteristic curve of a stock properly, and a general non-understanding of flashing, negative density, etc.
However over the last couple of days thanks to a lot of reading, and everyones posts, im pretty sure i understand how to flash a negative. I understand that testing is still important, but i just wanted to get my head around the fundsamentals, and understand what is ment when someone says they want to flash 20% (or 0.20) [i understand that % is not correct, but it seems like a lot of people refer to it that way].
I actually did some tests yesterday using 35mm stills photography (in preparation for the real test) and i had some really great results.
So once again, thank you all.
Benjamin Gilovitz.