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.



  • Content Count

  • Joined

  • Last visited

Community Reputation

150 Excellent

About melsmore

  • Rank
    Star Forming

Profile Information

  • Location
    North Wales
  1. Not far from me then, bit East of you on hols near Craster , fantastic skies here too... (Not tonight though).
  2. There's a Test Report by Alan Dyer of it in September 2020 Sky and Telescope too. (Page 68).
  3. And why not? It's always a joy to look at that combination.
  4. New sleeping bag for SD115S. The dog seems to have retired from security duties, hence the alternative.
  5. Excellent first light. Well done.
  6. That's not an "unboxing", it's just a box. You're taunting us.
  7. Yes, from me too. A terrific advertisement for TS and iOptron!
  8. New (to me) Vixen SD115S set up for first light. Birthday pressey from SWMBO.
  9. Very sorry, I just checked the current models of C8 and C925 on FLO's website and it is certainly no longer the case concerning the secondary mirror sizes. C925: Secondary Mirror Obstruction: 3.35 in (85.09 mm)Secondary Mirror Obstruction by Area: 13.1 %Secondary Mirror Obstruction by Diameter: 36.2 %Optical Tube Length: 22 in (558.8 mm)Optical Tube Weight: 20 lb (9.07 kg) C8: Secondary Mirror Obstruction : 2.5 in (63.5 mm)Secondary Mirror Obstruction by Area : 9.8 %Secondary Mirror Obstruction by Diameter : 31.3 %Optical Tube Length : 17 in (431.8 mm)Optical Tube Weight : 12.5 lb (5.67 kg) Sorry, next time I'll check before I post.
  10. My MAK127 is kept indoors (no cool room) and It takes 30 minutes or so to cool down - almost exactly what @vlaiv extrapolated from his! I plonk it outside first and by the time I've polar aligned my mount and faffed around it's just about good to go. Wooden sheds (in direct sunlight) can soak up a lot of heat and cool down slower than a MAK The only (very minor for double star observing) drawback I have concerning my MAK127 is that I can't use 2" eyepieces with it . Also, mine came with a RDF, and as I don't have GOTO, I'd have preferred a finder scope. @Stu recommended the C925. I've never used one, but I have had this SCT recommended to me for this by others too. Apparently, it is good because theirs have the same secondary mirror as in my C8 giving a much smaller % obstruction - more MAK like in fact . When you say "do double stars" do you mean "looking at them and seeing if you can split them", or do you mean "measuring their position angle and separation too"? If it is the latter, then there are other considerations and I would recommend you read Argyle's book before deciding exactly what you want. I should say that I have the first not second edition, but I expect the second to be better.
  11. Would that include "During the favourable opposition [of Mars] of 1892, W. H. Pickering observed numerous small circular black spots occurring at every intersection or starting-point of the "canals"?
  12. Thanks, very interesting link - especially the conclusion in section 5.1.3. I've always thought that the average cell size here is fine for telescopes up to around 12" ( can't remember where I read that) and I can't say I've ever changed to my Mak127 or TS80APO because of seeing. I've often had to wait one or two hours for my C8 to stabilise thermally though, and when I had an 8" Newton, I often had to swap to one of the others due to meteorological wind. CONCLUSION What all this implies is that it is possible for a significantly smaller aperture to outperform the larger one, but it requires them to be, and remain at a specific seeing error level, generally involving compromised seeing conditions. It is only possible when D/r0 in the larger aperture is ~4, or larger, in which case a smaller aperture with D/r0~2 will have - all else equal - better resolution and contrast transfer. In other words, smaller aperture could perform better while the seeing error is large enough, but if it lessens sufficiently due to seeing fluctuations, larger aperture would rebound and perform better. Typically, seeing fluctuations are wide enough for that to happen.
  13. Celestron Skyris cameras are Imaging Source. They say "Skyris cameras are not ASCOM compatible. However, they do work as DirectShow cameras with generic webcam software." I haven't tried it but there is an ASCOM driver for DirectShow here http://www.hristopavlov.net/ASCOM/ You could try that.
  14. The second one looks better on my tablet too. Really good.
  • Create New...

Important Information

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