Why you have to wet the film before processing?

Answer 1

Prewetting film before putting developer in the tank helps prevent surge marks from forming. *******

Check the development data for the film and you will probably find that this is not recommended anymore if you have a normal water supply. Not saying it hurts, but I've never pre-wet and never had streaking (surge marks), likely because I was taught to do 10 seconds of continuous inversion agitation at the beginning. If you are changing your process, each change is best judged by direct comparison, which means changing only one thing at a time. Should you wish to test, in this case I would expose a roll of film on one subject with no lighting changes, and cut it in half in the darkroom. Place each half in a separate but identified tank, use one batch of chemicals and develop one at a time. The only difference is that one should be pre-wet. Process and dry as normal, then examine very closely. Some people believe that pre-wetting induces base fog. If you see any difference, especially in the unexposed areas between the frames, you may have to adjust your process if choosing to pre-wet.