Using laser pens to test a surface

[mura_gadi (Steve)]

Hello,

In regards to testing the polish of a mirror surface, I watched Gordon Waite's youtube video "testing the polish on a 20-inch F3...". The test looked great, but no info on the strength of the laser I should be using.

Priced between $19-$40 for cheapies on the web and .1, 1, 3 and 5mw laser power rating.

Is there any point in getting the green laser at 532nm?
What Mw rating/power level should I get?
Can the laser be used for other optical tests?



Thanks
Steve
https://www.youtube.com/watch?v=gM6G398dy7I

[Rod]

Hi Steve

You just use a cheap laser pointer you can get anywhere for a few dollars.

I find it a frustrating test to use as the surface has to be extremely clean for it to work properly. I saw someone with experience on cloudy nights recommend this recently:

https://www.amazon.com.au/dp/B00LAX5...302_E_DDE_dt_1

I bought one. I haven’t used it on a mirror yet but it has impressive resolution for something so cheap. Should be good for checking pit sizes look even.

Rod

[Rainmaker (Matt)]

Originally Posted by mura_gadi

Hello,

In regards to testing the polish of a mirror surface, I watched Gordon Waite's youtube video "testing the polish on a 20-inch F3...". The test looked great, but no info on the strength of the laser I should be using.

Priced between $19-$40 for cheapies on the web and .1, 1, 3 and 5mw laser power rating.

Is there any point in getting the green laser at 532nm?
What Mw rating/power level should I get?
Can the laser be used for other optical tests?



Thanks
Steve
https://www.youtube.com/watch?v=gM6G398dy7I

Steve, the purchase and use of handheld laser pointers with output over 1mW in ACT is regulated and are deemed as prohibited weapons. There is however an available exemption from the Firearms Registrar (AFP-ACT) that allows the use of more powerful laser pointers by members of an approved astronomy society in connection with the activity.