Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

Laser Pointer Store

520nm Pointer for Astronomy Suggestions

RB astro

Super Moderator
Staff member
Apr 6, 2014
Power level choice is a bit tricky on these things - you want a visible beam even in clean outdoor air, so you need a fair amount. On the other hand you are standing out there in the dark with probably fully dilated pupils, so the chance that accidental exposure would do serious damage is a lot larger compared to the same power leven with contracted pupils in a daylight environment.

These things don't combine well, you need to somehow safeguard that noone can be hit by the laser beam or even a reflection off it from something like a window.

520 nm is a good wavelength though as it is very visible for a given power level. 532 is a tiny bit better but with dpss lasers you get temperature issues, sometimes emissions of 808 or 1064 nm light that is hardly/not visible but yet damages eyes and such, so the direct diode is a better choice.
Ben believe me, 20mW is plenty for astro work.
That's what I use.
And I agree, 520nm is ideal, given the temperature issue and IR or 532nm.