It's my first thermal. I played with it a tiny bit last night. It was 20* when I was out so I didn't play with it for very long. Shortly after start up, on several different times, the image would freeze just for a fraction of a second, and the image it froze onto would superimpose onto the live image. Is this normal?

Yes, It is auto calibrating. The term for this is a NUC (non-uniformity compensation). It will do it every so often. As the internal temperature in the scope rises it will become less frequent.

Thank You!!!   I was a little bit sick about it.

The image freezing, along with the audible click is the the thing nucing itself.  It’s part of the normal function .  The superimposed image means that the internal shutter didn’t close all the way .  That’s a sign of mechanical malfunction.  If it did it once I wouldn’t sweat it.  If it did it continually, I don’t remember the exact process on those but you can manually mic them .id turn it on , and nuc it about 50 times. If it’s a mechanical problem it might just be a tiny piece of trash hanging the shutter up .  Or just send it back to whoever you bought it from and tell them you want a new one

If the image stays superimposed, that’s bad.  If I’m misunderstanding, and you have a clean image after the nuc, then you’re fine and disregard what I said.

RTFM

Correct!  If image is superimposed (aka ghosting) then you’ve got a stuck shutter.  Covering the objective with the lens cap and commanding a NUC should clear the ghost image, at least until in NUC’s the next time.