Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

Recommended Posts

I have a revelation (GSO) coma corrector that I use on my 130 pds with a Canon 1000d. I have noticed that I am still getting some coma. My question is, do I need a spacer between the corrector and the T ring. I can't find any definite information on this but I read somewhere you need 75mm between the rear element and the camera sensor

Share this post


Link to post
Share on other sites

I think I used a 15mm or 20mm spacer when I used mine during the last Mercury transit.  The results looked pretty good, but there were no stars in the corners to judge it critically.

  • Like 1

Share this post


Link to post
Share on other sites

According to the specs you need 70 mm backfocus. The Canon has 44 mm and your T ring probably 11, so you will need 70 - (44+11) = 15 mm spacer to get it working correctly.

Share this post


Link to post
Share on other sites

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 account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By cwinstone
      Hello, does anyone know if my imaging train looks correct, and if it does, why am i still getting these coma errors?
      Could it be incorrect backfocus? Searching the internet makes me think my dslr is 44mm, adding the t ring (even tried a 1mm spacer too) gets me to the required 55mm (assuming that's correct)
      I have no idea how to solve this and i feel like I'm just throwing money down the drain fighting this in vien. Help would be much appreciated.
      Skywacher Evostar 72ed
      Reducer rotator for 72ed (needs this for extra distance to achieve focus, the reducer and adapter alone doesn't allow for enough outwards travel)
      Reducer/corrector for ed72
      Canon eos 650d


    • By Anthony RS
      Hello,
      Is anyone here using the TS Photon 6" F4 newtonian? I'm about to purchase it but I have some doubts and questions:
      1- Does it hold collimation well, at least in a single session?
      2- Is it impossible to balance in DEC due to its small dovetail or is it possible but harder?
      3- Is the focuser rigid enough or does it introduce tilt?
      4- Will collimating it be a nightmare?
      5- I'm really picky when it comes to coma, should I expect some coma on edges even while using the Skywatcher Aplanatic F4 CC?
      6- All in all, do you advice me to buy it or have some other option in the same price range.
      Cheers!
      Anthony
    • By avodcap7
      I have a celesctron nexstar 8SE OTA, to which I attach my focal reducer (0.63x by celestron), the a T-Adapter-SC, a t-ring and then my dslr. Does the T-Adapter affect the performance or use of the focal reducer?
       
      Emilis
    • By DJastrzebski
      Hey,
      For sale is Baader Rowe Coma Corrector (RCC I) in a perfect condition (used max. 2 times). £90 including delivery in EU. PP preferred. Thanks for looking!


×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.