On Tue, 21 Feb 2006 03:18:49 +0100, Vlad Krupin <
vlad.cnc@...> wrote:
> Doesn't glass (or at least most kinds of glass) tend to absorb UV rays? I
>
> was under the impression that this was the case. As a result I first
> tried
>
> using acrylic, and after finding that it scratches too easily, ended up
>
> using the thinnest glass I could find -
>
> http://www.krupin.net/serendipity/uploads/pcb_making_exposure_frame.jpg
>
>
> It sounds to me that using thick glass would seriously slow down the
>
> exposure time, especially for people who are using a less powerful light
>
> than the one you have.
>
>
> Vlad
I think plastic absorbs even more uv.
Ideally you have quartz glass, but normal, thin, glass will work.
ST