cosmic dave Posted February 21, 2012 Share Posted February 21, 2012 I have to say I was not that impressed with that 8 inch dob of mine, my 90 mm refractor seems to give a clearer view, anyway one more go next clear night and let's see what happens. Link to comment Share on other sites More sharing options...
Rusty Strings Posted February 21, 2012 Share Posted February 21, 2012 I'm very surprised it's not delivering Dave. Link to comment Share on other sites More sharing options...
catman161 Posted February 21, 2012 Share Posted February 21, 2012 No way,sorry to hear that.I love my 8 inch Dob Link to comment Share on other sites More sharing options...
Doc Posted February 21, 2012 Share Posted February 21, 2012 Whats exactly wrong with it Dave? Link to comment Share on other sites More sharing options...
Brantuk Posted February 21, 2012 Share Posted February 21, 2012 There's so many factors that affect the use of any scope. The 200P is a smashing dob but you may have a problem with collimation, or light pollution, or seeing, temperature, eyepieces, object position, etc, etc. Bring it to an obs meeting and I'm sure we can help you - it's a great performer when everything is right Link to comment Share on other sites More sharing options...
BAZ Posted February 21, 2012 Share Posted February 21, 2012 Yeah, there is a poorly dob there. It sounds like somethings not right. When you get a look at a star, put in an eyepiece around 8mm, and defocus it and let us know what you see. You should see concentric circles with a nice demarcated black centre. If it's triangle in shape, the mirror clips are too tight, I used a piece of baking parchment as a gap gauge, it's about 15 thou thick. You should just be able to turn the mirror by hand. I know this one from bitter experience, and was kindly put right by Barry from Beacon Hill. Dobs will never be as sharp as a refractor due to the central obstruction, but it shouldn't be that noticeable either. Link to comment Share on other sites More sharing options...
Rusty Strings Posted February 21, 2012 Share Posted February 21, 2012 My thoughts exactly, apart from defraction spikes, you shouldn't be able to see that must difference. Link to comment Share on other sites More sharing options...
Guest wisewoman Posted February 25, 2012 Share Posted February 25, 2012 Hey there, Is it a Skywatcher Skyliner Dob you have? i must say that I've been really pleased with mine. It is prone to misting up on damper nights but it's easy to improvise a dew shield. Other than that it sounds like maybe the colimation is out? Melissa Link to comment Share on other sites More sharing options...
cosmic dave Posted February 25, 2012 Author Share Posted February 25, 2012 Everything was cooled and used good quality ep, so its scope or seeing ? No propbs with light polution kim, lol Link to comment Share on other sites More sharing options...
tbird Posted February 25, 2012 Share Posted February 25, 2012 Hi Dave, don't be shy of popping round one evening and we'll have another look at it ( if you can remember the way ) Link to comment Share on other sites More sharing options...
cosmic dave Posted February 27, 2012 Author Share Posted February 27, 2012 Cheers paul will do. Think I can get there (god I thought I lived in the middle of nowhere lol) Link to comment Share on other sites More sharing options...
oldfruit Posted February 27, 2012 Share Posted February 27, 2012 Very surprised that your 90mm refractor is giving you clearer views. Would be interesting to have a look on Saturday night. Link to comment Share on other sites More sharing options...
cosmic dave Posted February 27, 2012 Author Share Posted February 27, 2012 Im thinking of getting a larger refractor now mark. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now