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BGazing

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About BGazing

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    Serbia
  1. Would it also have to do something with bino light rays coming out polarized?
  2. Your scopes are somewhat limited at how far you want to push their magnification. Achromat will show color and those little newts with spherical primaries peter out over 150x. I'd reccomend something around 4mm at most. Those scopes are not taking high magnification that well, IMO.
  3. I did just that...127 Mak to C8 and it makes sense, really. C8 is jack of all trades and will give you a lot of good views under dark skies.
  4. Well, this hobby makes you learn more about weather than about astronomy. Basically no weather is good for us, its either too cold or too hot or there is wind or no wind and high humidity. If by any chance it all comes together and it's perfect turns out I cannot go because of the commitments. But hey, this year I bagged 4 new moons at the dark site and I consider that a massive success before snows cut it off from our reach. Just came back today...we went for two days and the forecast was okayish for the first night and meh for the second night. One guy cancelled because he was rational. The irrational part of the group went and enjoyed two clear nights. The second one was high humidity, but still. I guess this makes it even for the night when I went and the forecast was clear...and we ended up under 100 percent overcast sky.
  5. 6mm would be very useful in your scope. 5mm T6 is my favourite Jupiter EP in 7.4 100mm Tak, and 4mm is probably the most comfortable on the Moon. If the seeing allows I would go to 3.5mm or even 3mm on the Moon, but Jupiter gets washed out. So, based on my experience, 6mm would be great for your 8.8. One more thing. With planets so low here (and especially for you up there), I consider ZWO ADC indispensable in my Tak for planetary. Cleans it up very well and you get to enjoy the views instead of some rainbow boil near the horizon. The trick is, you would have to use some barlow before the ADC to make your f longer (I use 2.5 PM) so you get to use longer fl eyepiece as your planetary. Eg. my 13mm T6 becomes 'Jupiter EP'. So...in your scope I would have both 5mm and 6mm and the ADC. But that's me. My EPs are multiplying like rabbits.
  6. Skiing pants are fine. Wool layer underneath. Basically, when you dress for prolonged sitting, you dress as if it were 15 degrees C colder than it actually is.
  7. Congrats on your new scope, I have only now stumbled upon this thread. Seems like we caught the dob fever in succession. It also looks like you held off Paracorr, which makes sense given the f/6 mirror. Just don't borrow one, you might like the look, I was told. I see that you are observing planets, and they happen to be quite low at the moment. I found dispersion to be objectionable to the point that I could not enjoy the views with planets so low without the ZWO ADC. Effects of dispersion get progressively worse with aperture, it is always present, at 100mm at my latitude the views with or without are night and day, SCT 8 the difference is astonishing. I compared C8 with ADC with 12 inch dob without and it was a no-contest. I would say that even a 100mm refractor with ADC would show more than a big dob under effects of massive dispersion. ADC even makes seeing look better because it cleans up the smear. So to enjoy planets in the coming years to the best extent, Jove and Saturn in particular, I suggest getting ZWO ADC. Its use is a bit more tricky with a dob (see online tutorial on lining up with the horizon), and you would have to use a 2.5 powermate to bring your f number higher and avoid astigmatism. But trust me, you need it for such massive aperture with planets so low. Just make sure to have 1.25 eyepiece in 2.5x more focal length than you would otherwise have...(e.g. in my Tak DF I use PM 2.5, ADC then 13mm instead of the usual 5mm for Jupiter). You may use it for your Tak as well, although you might need to buy additional EP or two...
  8. Does anyone have any ideas where TS sources its quartz mirrors? GSO quartz mirrors (one, to be precise) did really well in a double-pass test of Tommy Nawratil and Wolfgang Rohr.
  9. How different is that combo from say...this https://www.teleskop-express.de/shop/product_info.php/info/p754_Baader-Justierlaser-fuer-Newton-Teleskope-fuer-genaue-Justage.html
  10. 30mm is a proper 1kg godzilla, no wonder it flexed 14 inches at F5.
  11. Interesting @Stu, your Alkaid is 14, so larger than the production offered now. Have not read about mirror slip in 12s. How low was your low...I guess many nice objects are tantalizingly low up there, especially in summer. I tend not to observe DSOs under 20 degrees even at my dark site. Mirror weight seems to be the same no matter the option and the thickness is indeed to prevent astygmatism on a simple cell. Paracorr plus T6 is about the same weight as Ethos 17. Ethos 21 is on another level, a true beast. @GuLinux wrote that he experimented with 1kg and it was fine. Has anyone tried Sumerian's EQ platform. It looks unbelievably light at 2.5 kgs...it appears not to be a big issue unless one is sketching as Alkaids seem to track smoothly.
  12. @Piero @garryblueboy thank you both. Quartz should flex less while cooling so less astygmatism. But cooldown might be just as long, as @Piero noted. It appears that the older models had more problem with flex and slop, I have read better reviews recently, and that might be due to streamlining of production. Prior runs were often custom-made with many little tweaks. @garryblueboy was that 14 inches f5? trusses look looong...and the focuser is FTF, I believe a bit heavier than Moonlight CR2 they use now. Did it struggle with Ethos WITH Paracorr or without...and which Ethos...17 and 21 are true beasts. Did it go out of collimation when changing altitude? I've not read similar experiences with recent 12 f/5s...although have no idea whether it was Paracorr or not. Paracorr plus T6 is, I believe, below 700grams... @Piero any particular suggestions for collimation tools?
  13. Yes, the thread title is a knock-off of @Piero's Tak topic. I've read many good things about Sumerian scopes (especially the latest generations). There were some hiccups but they appear to have been sorted out and the production is reduced and streamlined. TS takes European orders and imposes uniform mirror choices. Unlike @FLO, TS is not fun to deal with, slow to answer and the answers are terse and sometimes cryptic. Michael (who makes the scopes) does not appear to answer the mails (at least not yet to me) so I am left with the collective wisdom of the forum to pry some more information. I understand that the 12 inch case weighs somewhere around 14kgs and the rest are truss poles. I'd be grateful if anyone comes up with the exact figure. Total weight is 16.5 as per both websites. F RATIO AND BALANCE - Most reviews suggest that 10 inches version are bottom light and that they are not suitable for heavier eyepieces, and I presume Paracorr. 12 inches should have a better balance due to heavier mirror. Going F4 would make it more stable, sticking to F5 would make it easier to collimate, be easier on the EPs and (who knows) dissuade me from buying a Paracorr...straight away. I do notice coma at F5... QUARTZ or PYREX - TS streamlined mirror offers to GSO Pyrex and TS branded quartz mirrors. At F5, both are available, at F4, only Pyrex. Quartz glass adds about 400eur to the bill, but the mirror seems to be 39mm thick just like Pyrex, presumably to avoid astigmatism because of the design of the cell. Lighter mirror would also be problematic because of the balance. So Quartz or not? There are fans behind, hopefully helping the cooldown and dealing with the boundary layer. Pyrex is slower to cool, but how much does that matter when you have the fans? Does Quartz offer much benefit when they are of the same thickness? GSO is Pyrex, Quartz is TS branded, anyone had any experience comparing them? So here are the options: F5 and Quartz - more expensive, easier on the EPs (although mine are all TV in 7-24mm range). Might still itch for Paracorr on top of it, adding to the bill. I know I will, sigh. Less stable than F4 balance-wise, although T6 plus Paracorr is almost like an Ethos. F4 - more stable, more demanding on EPs, Paracorr a must (there goes the balance advantage, although still less strain than F5 with Paracorr). Pyrex only. F5 in Pyrex, easier on EPs than F4, easier collimation, slower cooldown, again Paracorr dilemma. EQ Platform or not? Sumerian platforms are listed at 2 kgs weight...I find that hard to believe. What are your thought and suggestions?
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