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Old 18-05-2016, 02:38 PM
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RB (Andrew)
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Quote:
Originally Posted by johngwheeler View Post
My initial research suggests that 5-20mW would be adequate - with the higher power being preferable for urban use.
John, for astro work a 20mW green 532nm is more than enough even for urban use.
The obvious dangers are aeroplanes in the area at night (always be aware of aircraft) and also some of the cheaper 532nm green lasers don't have IR filters on them so they're dangerous because IR is invisible to the eye and they will be emitting more than the stated 20mW of visible light.

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