OK, that's going to be it....I'm putting my Meter's Thermopile Sensor back in the position where it belongs so that it is not near the meter.
I never keep it close to the Meter because I'm always afraid when measuring High Powered Lasers, a stray shot might hit the face of the Meter and damage it. I had to move things around a-lot just to try and get the Sensor & Meter in the same frame and yet still be able to read the screen.
The Meter is hard to get a picture off of because it's a light bluish dot matrix on a bright back light screen and when you turn a Laser on it makes it even harder to adjust everything so you can read the screen.
That is what the software is for, and again the software doesn't and CAN'T filter out any wavelength, nor can the Meter itself w/o a Filter placed directly in the beams path. As Coherent has already stated the Wavelength setting is only a correction factor of about 2% of the set wavelength for Sensors that are at the bottom or top of the Sensors range & filters out nothing, think about it; it can't.
I never even use the Wavelength setting on the Meter itself it's always OFF, my Coherent Main Sensor's Wavelength Range is 300nm - 11,000nm, I also have 2 other Coherent Sensor's and those 2 both are 190nm - 11,000nm
The LabMax software doesn't have an OFF position, but since everything I measure is within range of all my Sensors, that setting doesn't really do anything.
A Thermopile is NOT like a Photo Cell or something like a Andover LPM-1 which I do also own and you HAVE to properly set the Wavelength or the readings will be wrong because that Meter/Sensor is calibrated per wavelength and IR present in the readings will produce wrong results. So if you set the LPM-1 to 532nm and have lots of IR which the Aconsen has a ton of, the readings will be wrong on that meter, BUT not a Therompile; it will show you the SUM of all Wavelengths.
You'll also notice I don't hold the Laser in my hand and OMG I would NEVER hold the Sensor in my hands, in-fact I put a kozzy around it to shield it from any stray air currents.....but after adjusting the room temperature I do turn off all sources of air movements.
If this still leaves questions on Sensors, you might want to do some research on Themopile, Optical (photodiodes), etc; Coherent's site is a good resource as well many others of such nature.
Well I've pretty much wasted my entire weekend over this Laser, Ive easily lost in time more than the original value of it.
-Peace