Is polycarbonate a good alternative to anti-newton glass?

[AgX]

I have sunglasses made of polycarbonate with an anti-scratch coating that seem to hold up well. Perhaps there are products out there...

Such coating (a lacquer) would interfere with the AN characteristic.

 

[John51]

Hanging around Wings Camera in Atlanta, my source for used gear, somehow the conversation turned to Newton's Rings. An old hand, who'd done newspaper shooting, said that they used to use a light dusting of talc on a glass neg carrier! I suppose the fine grains separated the neg from the glass just enough; with moderate enlargement the grains wouldn't be visible. Of course YMMV.

Another one I've heard of is to use a hair drier to get the neg and carrier perfectly dry.

 

[AgX]

How would that work ??

The air that one blows onto the film has the same water content as the rest of the air in the darkroom.
By heating that air the dew point is raised, but due to the film and film stage cooling after minutes the dew point is lowered again.

Moreover, one may even argue that by heating that air by diffusion from the cold air the absolute water content around the film even rises, what makes the situation after cooling even worse.

 

[DREW WILEY]

The printing industry used something called offset powder. This was very finely sifted corn starch put into a little "puffer" plastic bottle when film was involved. But I don't like the idea of powder around optics etc; and corn starch attracts book lice. The modern replacement is anti-Newton aerosol spray. You can get this from the same outfits that sell scanner fluid. You don't want to breathe it. But you need to create a temporary cloud suspended in the air. So set the fan on your fume hood to low, blast a little cloud below that, then swish you film through the suspended cloud.
Don't spray your film directly or this will build up too much. It seems to stay put without migrating onto your gear, and can be later cleaned off if necessary with a good film cleaner like PEC. But I much prefer non-messy antinewton glass. If you have the correct type for the angle of incidence of your enlarging lens and light source, there will be no loss of sharpness even if the glass is used on both sides of the negative. And there's no need for a hair dryer (except for drying test strips of paper). Get a decent small compressor and, after washing your carrier glass, blast the water off into the sink using an air nozzle. Then let it air dry a bit further. ... or move to a dry desert climate, and then complain about the combination of dust and static!