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John

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Posts posted by John

  1. 10 minutes ago, jetstream said:

    🤣

    yeah and then are there those that mention battery acid in relation to lenses... dont know about you John but my skin sure wont take the acid lol! Ridiculous IMHO.

    The manufacturers really ought to put some warning stickers on the scope:

    "Warning: do not immerse the optics of this scope in battery acid, roll over them with a road roller, or allow high velocity rifle bullets to be fired at them. If such treatment occurs we cannot guarantee that the performance of the objective will remain fully up to the original specification"

    :grin:

    • Haha 3
  2. Delta Cygni can be challenging if the seeing is mediocre and the aperture small. Quite a difference in brightness between the components makes the 2.8 arc second gap between them seem tougher to prize apart than would be the case for an evenly matched pair.

    Your Tak 102 is made for such challenges though, even if the conditions are a bit sub-par :smiley:

     

    • Like 2
  3. I had my Vixen ED102SS fall off the mount onto a stone patio a few years ago. It made a horrible noise as it hit the floor but the damage was limited to the end of the dew shield and the focuser pinion, which got bent. No damage to the glass thank goodness and no effect on collimation either. Quite a tough scope !

    Other than that, I've been fortunate not too experience damage to the optics in any of the refractors I've owned.

     

     

     

    • Like 1
  4. This USA based optical company have a good reputation I believe. The smallest aperture they list is an 8" but they might be prepared to do something bespoke for you:

    http://www.rfroyce.com/stand_mirrors.htm

    You could wind up investing a lot in upgrading a 4.5 inch newtonian to deliver slightly better performance than stock when, for less cost, you could purchase a larger aperture optical tube complete that would offer a somewhat larger performance upgrade.

     

  5. 2 hours ago, globular said:

    I suspect the only horses head I'll see round these parts are in the fields down the lane.

    I've managed it here (Bortle 5) a few times with my 12 inch dob. Very challenging though - probably the most challenging DSO I've managed to see.

     

    • Like 3
  6. 50 minutes ago, Louis D said:

    At first I thought you had exchanged them for Meade 4000 Plossl smoothies, which being 5 element, Kowa made, are still sought after today.

    No, my exchange was for the Meade 4000 SWA, Japan made but with rubber eye cups.

    Back then they were expensive eyepieces here so I thought that getting a couple of them in exchange for 3 TV plossls plus some cash was a decent deal. The 4000 SWA's were not well edge corrected though - I was really disappointed in them. Those plus some poor examples of Meade 4000 plossls of the same vintage (again the Japan made ones but with rubber eye cups) that I acquired put me off Meade eyepieces more or less for good :rolleyes2:

    I have to be honest and say that I have not "sought after" anything with the Meade branding for many years now. My only remaining Meade item is a Japanese 4000 series UHC type filter in the 1.25 inch fitting which does seem to work well enough for what it cost (not a lot !).

     

     

  7. 10 hours ago, Alan White said:

    I did the same, first TV I owned was a 20mm plossl and it was a sweet eyepiece, stupidly sold to raise funds

     

    The 1st good quality 1.25 inch eyepieces that I bought were 3 of the "smooth side" TV plossls that I purchased new in a sale from Sherwoods in Birmingham. I went for the 7.4mm, 13mm and 21mm.

    I stupidly part-exchanged them at Telescope House for some new Meade SWA 4000 eyepieces (doh ! :rolleyes2:) then realised, to late, that the TV plossls were somewhat better optical performers and spent a year or so finding them again on the used market. Lesson learned !

    TH got the best of that deal !

     

    • Like 1
  8. 23 minutes ago, oscar_camilleri said:

    Hi All

    With recent weather , we were having I got bored and decided to undertake the mammoth task of updating the Ra/Dec  in my copies of Burnham's celestial handbooks (I know, must be crazy). 

    Anyways whilst l was looking for a consolidated list of double and multiple stars I stumbled across this website https://www.stelledoppie.it/ , not sure if any of you were  aware of it, but it has quite extensive and detailed database , so I thought I would share 🙂 

    That's a very useful resource - I use it all the time when observing binary stars :thumbright:

  9. One Russian optic manufacturer that you don't hear much about at the consumer optics end of things is Aries from the Ukraine.

    They are probably best known for the Chromacor optical corrector back in 2001 which was designed to correct the CA and SA in mid-focal ratio achromats (especially the 120mm and 150mm F/8 Synta made achromats) but also produce some very nice apochromat refractors including this 178mm F/8 fluorite doublet:

    Aries 178mm F8 fluorite refractor telescope. | Telescope, Fluorite, Aries

    The above scope was advertised a while back on the Astromart site "for a quick sale" at $14,990 ! :shocked:

    Here is one of theirs aimed (presumably) at the professional market - a 14 inch F/12 triplet apochromat:

    14frac.jpg.f577f8f3acb4c7bf6589440d3c3308bc.jpg

    A "snip" at 295,000 euros !

     

     

     

     

     

    • Like 3
  10. I enjoy listening to Daniel. His enthusiasm is infectious :icon_biggrin:

    I suppose that I try and capture a little of that when I post my observing reports on here. I usually do them immediately after coming in from observing or even during a session sometimes, while the experience is still very fresh. They are probably a bit "gushy" at times because of that but that's often how I'm feeling when I'm typing them in !

     

    • Like 3
  11. If you are trying to do what I think you are trying to do with the adapter that has just arrived, I'm not sure it would work with the Startravel 102 even if you could get the short 2 inch push fit adapter firmly attached to the SCT adapter on the diagonal. To reach focus with the ST102 and a 2 inch diagonal you will need to be able to fully insert the 2 inch barrel into the scope focuser, so the end of the focuser is right up against the body of the diagonal. The SCT adapter will prevent you from doing this as far as I can see.

    There is a version of the Celestron 2 inch diagonal that comes with both an SCT and a 2 inch push fit adapter. With this diagonal you unscrew the SCT fitting from the diagonal body completely and screw on the 2 inch push fit barrel in it's place. The diagonal will then fully insert into 2 inch scope drawtubes, as it needs to.

    If you could just get hold of the 2 inch push fit barrel part, I reckon there is a fair chance that it could work the same way with your XLT diagonal.

    Here is the diagonal that I'm referring to:

    https://www.harrisontelescopes.co.uk/acatalog/celestron-2-diagonal.html?gclid=EAIaIQobChMIxvqUtcu78gIVweR3Ch3N-g5_EAQYBSABEgJsjfD_BwE

     

  12. 57 minutes ago, RobertI said:

    Funnily enough, that’s what I was imagining I would end up with one day. Got the 102, just need to replace all my other scopes with a nice 10” or 12” dob. 🤗

    For quite a while the 4 inch refractor plus a dobsonian was my scope inventory as well.

    Then the refractors started to breed ....... :rolleyes2:

    • Haha 3
  13. 22 minutes ago, Stardaze said:

    How old do you estimate your 12” dob to be @John? Presume you’re the second owner if you had the mirror recoated? I’d like an Orion 12” and quality 102 refractor, eventually. Always great to have aspirations   😀

    The optical tube / mirrors date from 2005. I have the original optical tests / paperwork for it. It had 2 owners before me. On the side of the primary mirror is a further Orion optics sticker showing that it was re-aluminised in 2010 and Hi-Lux over coated. Back in 2005 I'm not sure that hi-lux coatings were applied as standard.

    The dobsonian mount was made for me by a member of SGL called Shane who is a bit of a wizard at woodcraft :icon_biggrin:

     

    • Like 1
  14. 1 minute ago, Barry-W-Fenner said:

    Thats a very good idea John, let down by 1 important factor. I'm useless at building things 😂

    To be fair, I could not have built a base for my dob to the sort of quality that my SGL friend Shane did for me.

    His design and execution was excellent and has lasted really well :icon_salut:

    • Like 1
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