Jump to content
  • Join the online East Midlands astronomy club today!

    With active forums, two dark sites and a knowledgeable membership, East Midlands Stargazers has something for everyone.

that dob of mine

cosmic dave

Recommended Posts

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

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

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

Guest wisewoman

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?


Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.