Quote Originally Posted by Scheimpflug View Post
If you are making & applying the emulsion yourself, is there any reason not to perforate the film base first, in the daylight, and then apply the emulsion afterwards?
As Denise said, it's not possible because the emulsion flows in the perforations (and outside the film), making a mess. I coat with a coating blade and the requirement for usable coating is that the film base is flat (without any holes ) and wider than the coating blade so that the blade runs on the film base, inevitably leaving some uncoated area on the edges.

So, the easiest way is to coat a wider coating, for example, 15 cm wide coating on 20 cm wide film base, and then cut it down to e.g. 4 slices of 35 mm film, and then perforate. You'll also get more than one roll of film with one coating, which is very nice because hand-coating on the table restricts the length quite a bit (I'd say 135-24 is practical maximum).

It seems like a lot of extra work to have to perforate it in the dark...
Well, the coating has to be done in the "dark" anyway (and the final steps in emulsion making, after sensitizing dyes are added), and perforating is quite easy compared to that. This is why ortochromatic film is so much easier to make, as you can actually use red safelight. If you are going to do panchromatic, it's better to buy night vision goggles and use IR light. I have bought the goggles so I can do panchromatic one day, but it will take time before I'm at that point. I have actually done nothing regarding emulsion making in a past few months, but I'll be back at it again soon.