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Stargazer McCabe

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Everything posted by Stargazer McCabe

  1. @Littleguy80 The Interstellarum Guide works as a stand alone. But if you have the Atlas it works to an even greater degree as the page references for the Atlas pages correspond directly in the Guide... I've just ordered a copy of Dobek's Revised & Updated Version of Barnard's Photographic Atlas of Selected Regions... It should be with me next Wednesday, so I'll let you know how that compares to all the others if interested...
  2. Thanks to everyone. I had no reason for my initial reaction to Didier’s suggestion other than just “gut feeling” I suppose... I now feel I can formulate a more informed reaction which still follows my initial one to be fair. It also allows me to make a more reasoned and informed “capital expenditure” application to the Memsahib ? (The joys of being married to a Global Commercial Director ?) I’m minded to apply for a 20” and if I get away with it ?? But I’d settle for an 18” or, if I pick my moment badly, a 16”? Thanks again to everyone who chipped in.
  3. The first doesn’t “go in any closer” to be fair. It is very similar to the one you have therefore. Overall quality of the photos is better to my eye. But no more detailed...
  4. I have both of these as well as the Interstellarum Guide The Cambridge Photographic Star Atlas https://www.amazon.co.uk/dp/1107013461/ref=cm_sw_r_cp_api_SIs7BbEK6XJG0 The Photographic Atlas of the Stars: The Whole Sky in 50 Plates and Maps https://www.amazon.co.uk/dp/0750306548/ref=cm_sw_r_cp_api_uKs7Bb6B87062 The photos and format are better in the Cambridge Atlas, however, the accompanying maps of the regions edge it in the second one... You pays your money... Or do as I did and elect not to make a choice and buy the lot !!
  5. This might interest those following this... http://astro.dialou.fr/materiels/optiques/orion-skyquest-xx14i/transformation-de-lorion-skyquest-xx14i-par-sud-dobson-partie-1/
  6. That all makes a lot of sense and echoes some of the conversations my wife and I have been having. Our reasons for considering the Truss design are exactly as you suggested. The Flextube, although great, is bulky and heavy. Both in terms of its base and Tube. As I have said in other replies there are pros to each route and it’s an interesting and good conundrum to have... Thanks for helping the deliberations ??
  7. @Stu John certainly has been exceptionally helpful and “responsive” to date. Whereas others... The Flextube could possibly “donate” more than just the primary if we went that route. The secondary could be used as it’s an OO 1/10 wave with heater and the focuser, although only a Moonlight CR2, could perform an initial task... However, to be fair, I could see the existing scope serving someone else for many years to come with its Push To capability with Serge’s Encoders. So I’d feel it a tad draconian to rob it of bits to the point it ends up being tossed...
  8. @Stu & @swamp thing Thank you for the swift and helpful replies. It certainly reassures that nobody thus far is saying Didier’s suggestion has a significant flaw. As you say Stu, the route of a new mirror from OO or John does allow a greater number of options to be considered. Focal length and diameter being the most obvious ones, allied to optical quality if we felt we could endure the sort of wait @faulksy documented so comprehensively ? To be fair, while I acknowledge a new mirror is bound to be better than the existing SW one (which individuals say are very roughly 1/6 wave on average), folks more experienced than me that have looked through it have said it’s one of their better ones. Therefore, if we were to commission a 14” there’s a strong case for Didier’s suggestion. Would we really see the difference that another few thousand pounds on the mirror would yield under the sort of skies and conditions we encounter..? Some might, but I genuinely wonder whether we would and whether that extra expenditure would “pass us by” being brutally honest ? An interesting conundrum to ponder. It’s increasing our understanding and knowledge so whichever way we go, we’re grateful for the input and thoughts. Thank you again...
  9. @Astrobits Thank you. I appreciate the guidance Nigel. I'll continue my research. It may be a better end result to get a known, conventional, mirror from someone like John Nichol and mount it in the conventional triangular mounting system... But I'll bear in mind your thoughts if discussions about using our existing mirror is to be pursued
  10. I'm seeking advice on a point brought up by Didier Vincent at Sud Dobsons in a recent email exchange. The DIY section seemed the best place for it, but if it isn't I have no objections to it being "re-homed"... In a nutshell I have been considering having a Truss Tube Dob built for us. I've been evaluating various options and companies / individuals that could assist us with optics and construction. We'd rather work with someone who can help us build a "custom" scope, rather than having the optics and accessories dictated to us and one individual who has been quite thought provoking is Didier at www.sud-dobson.fr In a recent exchange, I happened to mention to him that we currently own a 14" Flextube. In his reply he posed the question "why don't you convert that into a Truss if you are happy with the mirrors and size..?" Undoubtedly sourcing Optics from John Nichol or OO (if I can stand the wait !!) would yield a really good mirror. But while I've never had our 14" mirror tested, it seems a pretty good example and we've had no complaints to date. So I haven't dismissed this option out of hand. The secondary is of known 1/10th wave quality from OO. However, the construction of the SW Mirror and its cell is slightly unusual as the mirror is "ribbed" as shown below... Didier has commented that there are two ways he could incorporate the mirror. One way to do so would be to use the mirror and the associated supports supplied by SW. Along the lines of the "kits" he provides. http://www.sud-dobson.fr/kits.html The other comment he made referenced using only the mirror and adapting the design and construction of one of the mirror cells of his "bespoke" Compact Truss Dobs. http://www.sud-dobson.fr/compact.html While incorporating our mirror would save on overall project cost, my gut reaction to this idea has been to question the idea. But I have no real reason for doing so... Setting aside the fact that an OO or Nichol mirror might be of guaranteed, tested and higher quality, could those with experience and knowledge of mirror cells (such as @swamp thing, @mapstar, @Astrobits, @saac, @Chriske, @Peter Drew ) let me know whether there's any significant "engineering" or "design related" flaws to Didier's suggestion please ? Thanks in advance Simon
  11. @domstar The ES Dobs are pretty good now. The early versions had a few issues which the guys at Dakota Starry Nights detailed in their videos. But I believe ES did finally take the “constructive criticism” on board and revisions to design, manufacturing and QC have seen far less critical commentary. A Dob is a fabulous scope. Go for it... ??
  12. @MetroiD Rupert at Astrograph is Serge's Prime UK Retailer. But his price is similar to the 365 one. I think this is because the goods have had an "uplift" in price as shipping and duty has to be factored in... Nexus DSC http://astrograph.net/epages/www_astrograph_net.sf/en_GB/?ObjectID=11737062 or the Nexus II http://astrograph.net/epages/www_astrograph_net.sf/en_GB/?ObjectID=11737092 But I've always bought directly from Serge in Australia. On one occasion I used Serge's Courier of choice, DHL, as I didn't have any contacts in Melbourne flying to UK. 4 days door to door... I would go direct if I was you, as you'd be paying for only 1 lot of shipping and associated duty / import costs. Email Serge. he's exceptionally helpful and will bend over backwards to help...
  13. @domstar happy evaluating of your options. Do consider and test the weight of any mirror, cell and mirror box if you might have to carry the components from your flat. The design of classic Truss tubes as opposed to compact ones, as I mentioned earlier, does make quite a difference to the weight and bulk of the mirror box and base... A travel Truss is the lightest and most compact design. But be careful that doesn’t introduce a bit of flexibility and balance sensitivity if you ever migrate towards a wider 2” eyepiece...
  14. Okey Dokey. All I was trying to do was help the OP on his original question about a 10 or 12” so answered accordingly
  15. If you’re going back, picking everyone up on inaccuracies @Stu in this thread you’re going to be busy.... ? Notwithstanding the varied agendas I hope the OP managed to get something useful....
  16. I’m aware of that Stu. But the OP wasn’t talking about a 450... The size he mentioned in the OP is only made as a Flextube I believe But please correct me again if I’m wrong
  17. @domstar Someting seems to have confused @cloudsweeper in my reply given his reaction to it. I hope it was clear to you... If it wasn’t, do feel free to PM me and i’ll happily clarify or put you in touch with my friend.
  18. Depending on which Truss you buy, there really shouldn’t be any DIY, other than building the scope each time and collimating it. Make sure you see the scope before you buy. A classic Truss is a lot bigger and heavier than a compact or ultra compact. Have a look, just for comparison, at www.sud-dobson.fr/index.html He makes Classic, Compact and Ultra and lists weighs etc. It may give a guide. But a Truss doesn’t need DIY other than building it I believe
  19. @domstar To try and bring this back to being constructive after the last comment, he really enjoys his scope. And I too may move to a Truss Tube in due course. The Flextube is a more simple setup if you’re fit and strong and have a stopwatch running !! But a Truss Tube is easier in terms of weight and compactness. His takes up less space in his car when we travel If you were to time him setting his up and me doing mine, there’s probably 10 minutes in it. But his packs down smaller. In years to come, as I say, to maintain aperture, I may migrate from my 14” Flextube to a similar sized Truss... The mirror is no more vulnerable in his than my Flextube and sits safely in its cell for travel. We both use shrouds. So there’s no difference in dew formation and stray light. Without a shroud the Flextube May be marginally better at dew prevention and stray light control. But not by much
  20. The OP expressly asked about Truss Tubes...
  21. A Flextube is “almost” a solid model. But it’s UTA slides to its observing position. Therefore it almost holds collimation like your solid Tube and most times it’s only the Primary that needs a tweak... A Truss Tube is a completely different beast requiring construction each time. Consequently, as the OP expressly stated he was going down the Truss route, it’s important he understands that his scope will probably require both secondary and primary to be checked each time the scope is assembled. It doesn’t take long. But a Truss will need a bit more checking than a Flextube Skywatcher...
  22. There’s a difference between a Flextube and a Truss Tube. My Skywatcher Flextube holds collimation pretty well. And only a minor adjustment to it is needed each time as Doug said about “Skywatcher Dobs”. A friend with a Truss Tube has to assemble his scope each time and has to check secondary and primary each time. It doesn’t take him long. But the last post from Doug is a little confusing. Skywatcher makes Flextubes. I believe a Truss Tube will need both secondary and primary checking each time, but as with my chum, it won’t take you long once you’re used to it...
  23. Brilliant. It was an amazing conjunction. Glad you got to see it John. You’re not too far further North than us. Stunningly clear at the moment...
  24. Apologies for the poor iPhone photo, but visually this is worth getting out there for right now. Sunday evening. 16:45
  25. @Victor Boesen, there are some exceptional reviews that Matthew @DirkSteele has done on the smaller Takahashi Scopes. He has reviewed just about every permutation from a visual perspective www.alpha-lyrae.co.uk/my-equipment and this site does similar with comments on both visual and imaging https://www.scopereviews.com
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