First telescope under Bortle 6 skies.

[Pixies]

Hi all,

I am looking to get my first telescope (although have been viewing with bins for several years). I was going with the usual newbie choice of a Skywatcher 200p Dobsonian, but find that there are none to be found for sale anywhere. I guess the lock-down means that lots of people are finding time to discover new hobbies. It's great that lots of people are now interested, but couldn't they wait until after I had bought a new 'scope! 🙄

Another option is the Bresser 8" Dobsonian, so I'm considering that (although it's a little more expensive). As I'm up in Scotland, the skies are getting pretty light now - so I could wait until August, when there might be quite a few going second-hand! 😉

Anyway, I live in a Bortle 6 region - and there's this blooming street lamp in the lane at the end of the garden, so it's not the darkest around here. Dark skies are pretty close-by and I have an old campervan to help transport things, but I'd really want to do most of my observing from the back garden.

So my question is.... is there a better option for my situation than a large-ish Dobsonian? Would a Mak-Cas be a better choice? I'm not particularly interested in imaging and I don't mind star-hopping to find things, in fact that's half the fun of it, so a GoTo isn't a high priority. DSO are what I like viewing (or trying to view) in my bins. So normally you would think a big Dob would be the most suitable choice for me. But would it be a waste of aperture with all the light pollution around me?

£400-ish budget.

 

Cheers

[Louis D]

An 8" Dob is a lot sharper to my eye than a 5" Mak if we're comparing in the £400 range (don't forget to budget for a decent mount and tripod for the Mak).  The Dob is just a single parabolicly curved primary mirror and a flat secondary mirror.  The Mak has two spherical curves on the corrector, a spherically curved primary mirror, a spherically curved secondary mirror, and a flat in the diagonal.  It's a lot harder to get 4 matching, well figured spherical curves than to make a single, well figured parabolic curve and a decent flat for £400.

Once you pump up the power, Bortle 6 skies become a lot less milky.  I should know, I observe under them in my backyard.

As long as you can block the light from the street lamp getting to your telescope and eyepiece, it doesn't impact your views all that much.  I had to put my recycle bin on top of my garbage bin last night to block my ******** neighbor's unshielded back porch light that shines like a beacon into my backyard.  Talk about light trespass.

Even in twilight, you can observe solar system objects and star clusters; although you're so far north, the planets must be really low for you, so it might not matter how dark the skies are if they're on the horizon.

As long you have nearby dark skies, you should be able to observe in those directions to good effect.  My nearby cities lie to my west, so I can't observe that way at all.  Smaller towns lie north and south, so the skies are a bit better in those directions.  However, it's just farmland to east, so I can get nice views in that direction.

The Bresser/ES Dobs have really good trunnions for the altitude bearings, so balance is less of an issue for them.  I've read they are better in other ways than the Skywatcher/Synta Dobs, such as the anti-reflection coating in the tube.  If you've got the time to observe, why wait?  The summer has many good objects to observe.