Had to choose between a 8 inch dob and a 6 inch SCT for my backyard setup

Went with the dob because it was $200 less and I figured aperture wins for star clusters, but now I'm fighting with collimation every time I roll it out onto the patio and I'm wondering if any of you have regretted not getting the SCT for the grab-and-go factor?

2 comments

2 Comments

jessica_miller21h ago

Honestly, the collimation thing is rough on some 8 inch dobs, but you might be overthinking it a bit. F/6 and slower dobsonian mirrors hold collimation way better than the fast f/4 ones. If yours is f/6, a quick tweak with a laser collimator takes like 2 minutes and you're good for the whole night. I'd rather have that extra 2 inches of aperture for the Orion Nebula and globular clusters than a 6 inch SCT that needs to cool down for an hour anyway. The SCTs are grab-and-go but they also have that central obstruction that kills contrast on planets, and the 8 inch dob will still show Sharpless 2-173 in your backyard without any fuss. Just grab a cheap Cheshire sight tube and mark your secondary mirror center with a dot, and the collimation becomes way less annoying.

charles67820h ago

Buddy of mine went through the same thing, sold his dob after three months and bought an SCT. Now he complains about dew on the corrector plate every single night.