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Subject: Re: [Homebrew_PCBs] overexposure

From: DJ Delorie <dj@...>
Date: 2016-07-07

"Cristian crissstian@... [Homebrew_PCBs]"
<Homebrew_PCBs@yahoogroups.com> writes:
> How much overexposure (%?) can cope the UV sensitive coated PCB, please?

Along with "it depends" - some anecdotal information...

When I was calibrating my UV box (get a transmission step wedge, they're
cheap and you'll know you're doing it right) I found that +- about 2-3
steps would still come out usable. That works out to a 50% to 200%
exposure.

So there's a pretty big range of "works" with a smaller sweet spot in
the middle that you should aim for.