I’ve been doing a lot of film processing with my students of late, and drying the film properly is inevitably a consideration. In my experience, this is one of those elements of analogue photography that is very much a matter of craft. No two photographers seem to have quite the same process; indeed, all possess little rituals and sequences as individual as they are.
A key question is what to dry the film with. Fingers? Microfibre cloth? Chamois leather? A few years ago, I came across Barry Thornton’s advice to use a film squeegee. He was absolutely convinced this was the best way, although he did attach some provisos.
A significant number of films later, I can concur with Thornton’s advice. However, some of my films have the dreaded long, even scratches down their length, so I have learned the hard way to take his provisos on board too.
First, the squeegee should be pre-soaked (with a dash of wetting agent in the water), so as to remove the particles that create the scratches. Depending on where you live, differing amounts of matter is contained in tap water, and you may well look (as I do) to distilled or de-ionised water as a more reliable alternative (I buy the kind of water used for car batteries, which is relatively cheap and available in five litre containers).
Second, the film should be soaked for a little time in the clean (de-ionised, etc.) water with a little wetting agent. The amount of wetting agent itself is subject to a little alchemy, although I follow Ilford’s recommendation for dilution that comes with Ilfotol.
This procedure is reliable and produces consistently clean negatives. It goes without saying that the film squeegee must be in good condition (I simply replace mine regularly to avoid degradation), and while I can’t say that scratches don’t creep in from time to time, it is the best method I personally have used. This is a craft you must learn first hand, so my advice might not be the perfect method for you, but it could be a great starting point.
* I write 'drying' here for simplicity, but it is more accurately the first part of drying I'm referring to, i.e. getting most of the water off the film before it is hung up to dry.