GoTo scopes and astrophotography

I’m looking for a telescope upgrade over the basic Orion 8″ Dobsonian I started with. Main things I want are GoTo and the ability to do introductory astrophotography. I’ve been hoping to avoid an equatorial mount because the hassle of setting the scope up precisely seems like an impediment to casual use, particularly since my usual viewing site doesn’t have a clear view of Polaris.

So I asked a knowledgable-seeming guy on Reddit for his advice on whether an alt/az mount with GoTo was sufficient for long exposure astrophotography, and here’s his reply. (Left anonymous).

You can get limited results from a non-equatorial single-fork mount for DSO photography, if the mount supports “wedge” mounting. This aligns the azimuth axis with the earth’s rotational axis and allows for equatorial-like tracking for long exposure photography, without field rotation.

This is a good option if you are doing wide-field imaging (which is also good for beginners). The tracking motors in most single-fork alt-az mounts are simply not accurate enough for high-power long exposures. The NexStar SE mount, for example, doesn’t even use worm gears (the NexStar “Evolution” mount does, however).

The double-fork models from Meade (LX series) and Celestron (CPC series) are wedge-mountable and people are able to get very good results out of them. Wedge-mounting can be an advantageous configuration, especially when dealing with large, heavy telescopes that would require an obscenely expensive equatorial mount to carry properly.

That said, if you’re serious about getting started in DSO photography, you really should invest in a proper equatorial mount.

I guess I shouldn’t be surprised there’s no shortcuts.

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