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.

Welcome to Stargazers Lounge

Register now to gain access to all of our features. Once registered and logged in, you will be able to contribute to this site by submitting your own content or replying to existing content. You'll be able to customise your profile, receive reputation points as a reward for submitting content, while also communicating with other members via your own private inbox, plus much more! This message will be removed once you have signed in.

  • Announcements



Advanced Members
  • Content count

  • Joined

  • Last visited

Community Reputation

3,215 Excellent

About Lockie

Profile Information

  • Gender
  • Location

Recent Profile Visitors

4,522 profile views
  1. I'm guessing it wouldn't hurt to have an extra long flocked due shield, long flocked baffled tube, and slow f-ratio to help off set the lack of coatings. p.s. Sorry Fishie for jumping on your thread. Any thoughts on which direction you'll go with your project?
  2. I'm going to try not to worry about coating any lenses I get round to grinding and polishing. I'll be too busy worrying about getting a reasonable figure and having the skill to do so! Yes non coated lenses will have less contrast, but if you want the highest contrast and highest Strehl refractor, my feeling is to save up and buy one from a company that has spent many years applying the art and money in kit to do so. for me grinding and polishing my own optics is more for the personal achievement and satisfaction than anything else. If any I make turn out reasonable i.e. 1/4 wave 0.8 Strehl and above, I'll be very happy indeed, maybe even if the contrast isn't top notch.
  3. I wouldn't do a triplet first, even if he has mirror grinding experience I still think he should go for some kind of doublet. I wonder what he will do?
  4. Hi Chris, is there a reason you would go for a Fraunhofer first? EDIT: just had a quick Google and seen that the Littrow can produce multiple ghost images...hmm?
  5. Wow in that case yes please, Peter! I'd be very happy to look after them until I can turn them into hopefully working optics I'll PM you after work tonight to sort out postage, cheers
  6. Sounds wonderful, Peter I certainly have the inclination to do so, only it might be some time before I've completed my mirror, plus a scope to go with the mirror. A very kind offer, but it might be a bit early days? Having said that, let me have a think? I could always buy the blanks and shelve them until I'm ready
  7. Not Chris Lock? don't trust him as far as you could throw him....although that's probably quite far considering how thin he is
  8. cough cough, I have a feeling that might have been my fault?
  9. Looks lovely, Fozzie, as said especially with the long frac Chris
  10. Spectacular! Lucky public at your outreach event
  11. A very natural and detailed looking Jupiter, very good indeed!
  12. Sorry to the OP for slightly digressing, but they had one of those scopes on ENS not so long back..I very nearly bought it and put it on the plastic!
  13. Wow that's a wonderful ambition you have there Fishie, I can't confess to having the answers to this one other than it would be flipping difficult. As a fellow mirror grinder you'll know that there is literally tons of material out there, but I've not seen anything on grinding, polishing (and possibly figuring) a triplet. Then again I haven't looked that deeply into triplets so maybe there is stuff out there? I'm personally tempted to try a long focus Crown and flint achromat as my next project, I've seen a book on the subject and figure if I read it enough times I might just stand a chance! The achromat would be relatively easy compared to the triplet I should think, 4 shallow spherical faces for a long achromat, and 6 potentially deeper curves for the triplet (unless you want a slow triplet which might defeat the object?), then of course there is the extra engineering involved with the cell for a triplet, as discussed above. Have you thought about cutting your teeth on a 'relatively' easy long focus achromat doublet? It might be a good stepping stone to your goal
  14. Either seeing conditions favoring the smaller aperture, or your fast Newt needs it's collimation tweaking.....or both Or your 10" has 1/4th wave optics, and your ED120 is 1/8th.