First Scope Advice (8" SCT)

[nearlycritical]

Hi,

I have recently caught the astronomy bug and have been madly researching for many weeks the different types of scopes available, their advantages/disadvantages etc.

I have 95% decided an 8" SCT is the best for what I want, decent aperture, portability and the ability the ability to view planets and DSOs. I figure this type of scope will give me plenty to see for years to come and then I can see what comes next after that.

I am interested in the Celestron C8-SGT (XLT) and a 5GT mount with GOTO, this seems to be the best mix of value for money and good quality, many reviewers and forum members like this scope and its siblings.

I would like some advice on which accessories I should get to make the most of it, the package ships with a spotter scope and a 25mm eyepiece. I am thinking a 9mm and a 15mm eyepiece would be good to start out with - recommendations?. Also bobs knobs to help collimation, a 2x barlow and maybe some filters (lower priority).

Any tips from more seasoned forum members would be greatly appreciated :)

[madwayne]

Welcome to IIS!

Good choice, but then I have a Meade 8" (never needed collimation in the 6 or 8 months I've owned it) so what else am I going to say. If you get the astrophotography bug you will be well served as you will have an EQ mount already.

Personally I would ditch the filter buying idea (yes I have a couple of dust collectors clogging up my accessory case), except a moon filter for $15 or $20. Instead make sure you get some dew protection, dew shield and dew zapper as an example (and yes get both). A 12V power tank (or car jump starter kit) should also be on your list. Dew shields can be hungry on power so go to your local car accessory store and buy as big as you can get.

Also join your local astronomy club. Our club (Sutherland Astronimcal Society) is fantastic, very friendly and full of helpful tips and tricks. Not too mention our two dark sites around southern Sydney and other different viewing locations members have told me about.

I'm sure other IIS members will come along and offer their more seasoned advice but this is just my two cents.

Good luck with your shopping and most importantly clear skies (although once you do buy it be prepared for two weeks of cloud - happens every time I buy somethng astro related).

[Matty P]

Welcome to IIS! :)

Wayne has pretty much said it all but I will add my 2 cents.

For your first scope the 8" SCT is a very good choice for a beginner in terms of aperture and portability. I recently just bought a C8 myself and loved it from day one and I'm sure you will to. The 8" aperture is great for peering deep into the universe but at the smae time wont break the bank.

If you catch the astrophotography bug the advantage you will have is that you already have an EQ mount. The only problem if you want to image DSOs with the C8 is that it has a very long focal length - 2000mm. This gives you a very small FOV but can be easily fixed with a focal reducer.

I would suggest a high power and low power EP to start off with. This will give you a choice of magnification to use. A 2x Barlow is great when you that extra bit of magnification.

Most scopes hold their collimation very well but Bobs knobs should be in your to get list.

Hope this helps and keep asking questions. :thumbsup:

[asterisk]

Hi

Welcome to IIS. While I can't lay claim to being "more seasoned", I have exactly the same setup as you and I find it excellent for both viewing and photography.

I strongly endorse Wayne's suggestion re dewshields and heaters - I still remember my first night when my viewing stopped at about 9.30pm because dew had formed on everything. I can recommend the heated dew shields from:http://www.astrozap.com/pages/dew-heat.htm - scroll down and you will find one for an 8" Celestron SCT. The CG5 GT mount needs an external power supply supplying over 12v at at least 2 amps or it gets upset and stops slewing correctly.

By the time you add a dew controller, heater bands for eyepieces, heated dewshield to your mount, you will find you need a good power supply.

As regards eyepieces, I eventually went down the 2" road and am very satisfied - I use a 30mm, 20mm and a 2x barlow - gives a good range of magnifications with a wide field of view. I have other eyepieces, but tend to mostly use these ones.

The CG5 mount is strong enough to support up to 15kg on the OTA side which means you can add a guidescope later with no difficulties.

Cheers

[iceman]

Hi there, and :welcome: to IIS!

Keep asking questions! You're in for a great time.

[citivolus]

:welcome:

I'll start off saying that I never once regretted my 8" LX90 purchase. I think I managed to stay at 8" for two years before moving up. Don't go near the dob row at a star party :lol:

Seriously though, that size SCT will do quite a decent job in a back yard.

My comments on a barlow: I think I've used mine four times in the 5 years since I bought it. Maybe I should list it here for cheap... It is ok when you are starting out, but once you have a bit of a selection of eyepieces you'll likely find it is not used. If you have a 9, 15, and 25mm on that scope, a 2x barlow would give you 4.5mm, 7.5mm, and 12.5mm, which honestly wont be as useful as it sounds. 4.5mm would never get used except maybe for collimation, double stars, or in really, really good seeing, and 7.5 may get used but is fairly close to the 9mm which will be sharper as it is not barlowed.

I'd venture to say 8, 12, 17, 25, and 32-35mm would be good target focal length eyepieces for that scope. On a pressed budget you could to that with a 35mm, 25mm, 8mm, and a barlow.

Regards,
Eric