"John Jardine." wrote:

Yes. Tracing paper/greaseproof paper seems distinctly better than clear
film. Bit queer, as I'd have thought the 'frosted-glass' finish would have
dispersed the UV light, much the same way as there still being daylight
after the sun has set. Maybe clear OHP film happily allows UV to bounce
around within the film thickness.

We had the same problem making holograms.
The film was temporarily stuck to a glass plate
with a thin layer of naptha. Under certain conditions
the light would bounce around inside the glass like
an optical fiber leaving unwanted tracks on the film.


Last week did some quickie SOT23 to DIL adapters. Samsung ML-2250 laser,
600dpi. Single sheet. Very nice results.
john