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Kinda wild you can just order an astronomy laser
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this post was submitted on 29 May 2026
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Chapotraphouse
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Some astrophotography nerds will use a laser to align their equatorial mount for proper star tracking. I use a polar alignment scope instead of a laser, but there are several non-GOTO eq mounts you can still pick up in 2026 that use a laser pointed up into the sky for an alignment w the North Star/Sigma Octantis.
Wait how does that work? I shine the laser into the north star, and how does that relate to calibrating my mount?
It's a very very rudimentary way of doing it. Cheaper, low end eq mounts do this. I think iOptron offers it still on some of their lower end stuff. The low end stuff is mean for wide field astrophotography, like Milky Way photos as opposed to stuff like nebula photos, and milky way photography is done w wide-angle lenses so half assed accurate polar alignment, like what you'd get w a laser is accurate enough for something like milky way photography with a 35mm lens. You won't be shooting 2 minute exposures w a laser aligned eq mount, but you certainly can do 20-30 second exposures w a wide angle lens, on a horribly aligned scope before you get star trailing.
Laser is integrated into eq mount. Point laser at North Star. Once aligned, you use a ball mount to get the camera on whatever you're looking at, then once aligned the head just rotates at the same speed the earth turns.
It really is just pointing the laser at the North Star as best you can.
but like.. how does that work?
By shooting the frickin' North Star with frickin' lasers
Through geometry, you can make an equatorial mount rotate at the same speed as all stars in the sky, which is the Earth's sidereal rotation rate. If you align the mount to the axis of Earth's rotation, it'll do so in parallel with the stars so any camera mounted will be able to get long exposures without blurring due to relative motion.
You can pin down the axis of rotation with some trigonometry but you can also do it quick and dirty by sticking a laser on the mount's rotational axis and pointing it more or less at Polaris or the Southern Cross if you're on the south side of the equator. If you've got a fancier telescope you'll just type in your coordinates and it'll automatically align.
ok i was thinking like it's relying on the laser reflecting back.. but its just following the path of the laser right? i've got the dumb
Yeah you just point it until it points mostly at Polaris
Lol that was exactly my thought too, and that's why I asked the question.
Fascinating. Thanks for taking the time. Back in middle school I was part of the astronomy club, and we'd calibrate our equatorial mount by using a little telescope with a reticle pointed to a known coordinate or star in the sky. It was such a pain goddamn.
The laser isn't for alignment or tracking. It is used as a guide source for adaptive optics systems to correct for atmospheric distortions.
No, the laser is used for polar alignment. It's not correcting for distortions. Thats what image stacking and post processing is for.
It is quite literally pointing it at the North Star or Polaris Australis to get on a polar alignment.
You aren't doing two minute nebula photos w it, but you can get aligned good enough to take 20 second photos w a wide angle fast lens.
Backyardastrophotography and Nebula Photos have a video or two showing them doing this exact thing on YT, with a laser if you need reference
I'm using a DSLR, not a telescope