billhinge

There are a multitude of threads on cloudy whatsits; quite a good one where some guy sent his back to Celestron and they stated in the work to be done that they would be rematched. However having taken mine off a couple of times there were no manufacturers marks or serial number on my C11 so I made my own. If you think about it the corrector is a thick piece of glass resting on a metal ridge held down with a plastic ring and some screws. Hardly a precision tuneable optical cell. Then there is the back, how do you know that all the optical elements are aligned? You probably need the advanced hotech laser with the new v9 process to check that There is an Italian company that sell replacement correctors, how would they match to your Celestron if they never saw it? Another thread some guy said he tried the corrector in various rotations with star test in between and there was not much difference. Personally I don't think it makes a huge difference, I don't think a SCT is a ultra high precision scientific instrument depending on micron level tolerances but it comes down to belief really

Thanks for the answers and link. So for my APM example "For systems of diameter up to 152mm Wave front error RMS is no more than 0.035 of wave-length at 532 nm. Wave front error p.t.v. is no more than 0.24 of wavelength at 532 nm" ) ) 0.035 rms is slightly better than 1/8 or 0.95 Strehl which seems a common quoted figure, OK so far, but ptv is quoted 0.24 which is slightly better than 1/4 or 0.745 rms which seems twice what the rms value quotes for the same lens (in the wrong direction) This is from an APM - LZOS Telescope Apo Refractor Astrograph spec https://www.apm-telescopes.de/media/files_public/typiegbv/APMApo-Linsen-Spezifikationen.pdf It also has specs for scratches and bubbles but I don't expect any scratches or bubbles on an expensive lens 🙂

When I was building an 8.5" pyrex telescope mirror in the 70's the books e.g. Howard and Fullerscopes used to say aspirational optics should be 1/8 to 1/10th of a wave. Looking at modern optics you see 1/4 of a wave and it often seems 1/10th is premium grade. Are things measured differently now or were the old 1/10th wave claims just bs? (I think the 1930's telescope books used to say 1/4 was OK but I think I saw Planewave quote 1/20) Do the figure work the same with refractors? (just looking at APM "For systems of diameter up to 152mm Wave front error RMS is no more than 0.035 of wave-length at 532 nm. Wave front error p.t.v. is no more than 0.24 of wavelength at 532 nm" ) )

New toy arrived special order from Germany, got it on 10% discount lol, need to get some tubes now Just need a matching StarFire now https://www.astro-physics.com/bpffc

Took my corrector off and started cleaning. I hadn't used my C11 for about 7 years and there was a ring of smeared cleaner (alcohol based) around the plate causing a purple discolouration. Two afternoons of patient dabbing with distilled water and a little soap seems to have removed 99% of the residue. Almost as good as new now. Seems these alcohol cleaners are a bit hit and miss (I have a big bottle of pure acetone just in case) Mirrors look good so not touching them I had flocked my tube with proto star flockboard some years back, still looks good. Next step to give the corrector a final clean and re-collimate (with Hotech) Still pondering whether to drill the tube and tap the holes with 3 corrector centering derlin tipped screws (from the finder 😉 Hopefully my Feathertouch focuser will arrive soon, it will get motorised with a Primaluce motor All that done its almost like getting a new planetary scope for nix (I fell out of love with it in favour of an easy to use small Apo triplet)

I decided it was always going to be an uphill struggle (I do have parallels on a fast mac - 2018 macbook pro) but I decided it was easier to just get a windows box, do you enjoy pain ? Macs are great but fact is most astronomy software is windows, once you give and go over to the dark side in then your opportunities really open up So choices are either cheap laptop DIY mini pc solution etc - would support remote control Pay the money and just buy an Eagle and bits - does support remote control from inside I chose the latter

yes, I had the TV, I looked at the Barcon and and Zeiss Abbe but I knew if I didn't go with my heart and go for the unobtanium fluorite I would kick my self for life wondering what it was like I'm building my retirement kit before brexit 😄

I had a x2 Powermate, I've ordered a Baader Fluorite Flatfield Converter, my equipment is similar to yours but I plan to use them for photographic . I'll let you know in due course how I get on. Need to dismantle and tune my C11 first 😀

Also you may want to read the cautionary tale here before you take the front off https://www.cloudynights.com/topic/663447-apparent-need-for-hotech-sct-collimator-because-celestron-does-not-assemble-their-edges-correctly/?hl=carbon tube about total mis-alignment of front and back (note hotech users there is a new manual v9 - site still shows v8) I have a hotech by the way and I used protostar flockboard - draw your own conclusions 😂

Hi Looking to buy a planetary camera mainly for my C11 XLT on EQ6-R. Expected use at focal ratio F10 to F30 with quality barlow but possibly also for the 80mm f6 APO; looking for a global shutter. C11 will have a motorised Feather touch for focusing, connected to an Eagle 3. If money isn't a factor which would you buy? the ZWO ASI 174MM or the Flir equivalent IMX174 https://www.flir.co.uk/products/grasshopper3-usb3/?model=GS3-U3-23S6M-C or alternatively a wildcard Moravian C1 IMX250 https://www.gxccd.com/art?id=556&lang=409 probably 5Mp ( or even C1+ https://www.gxccd.com/art?id=590&lang=409 - I know you don't need cooling for planetary but it may be useful for something else?) I'm waiting on delivery of a Moravian KAF-8300 with filterwheel and OAG so got deep sky sorted ( C1 could double as a guider and fit with the Moravian kit & software and C1+ can be used with the filterwheel, so only one filterwheel and filterset required) I know many people like the IMX174 but I also researched the IMX250 and I like the spec would appreciate a reason why if possible, I'm looking for capability and quality not price 🙂 thanks

I have the Wave 80mm APO version of the Altair which I purchased when it first appeared about 8 years ago. It originally came with a very good 3" crawford but I believe the new version has a new R&P (maybe 2.5"?) Optically it is very good, at the time rumour had it that is was a factory variation of the APM / Teleskop Express refractor with some Altair sauce on it, I assume the larger ones are similar I assume you mean the Altair Wave APO series , Starwave is the cheaper doublet series Comes in a nice hard carry case There is quite a lot of info if you search "Altair Wave" on here

answering my own question, I already have a Sesto Senso focus controler, looking on the primaluce website they offer it as an option to the SCT they sell coupled with a feather touch so I may go down that route. The argument against having a moonlight etc is that it uses up back focus , no idea if it's a real world consideration just what I read.

Any opinion on best approach, buy celestron motor for 11" xlt or buy baader/moonlight then reuse my primaluce sesto senso 2 on the baader The celestron is obviously cheaper and I could run it from my eagle but would it be as accurate as a baader?

Thanks Alan I have about 20x 10 mins of Ha, SII and mainly Blue to add, I'll try over the weekend!

My Bob's knobs seem quite stiff to me. I bought one of the Hotech laser devices many years back https://www.firstlightoptics.com/hotech-collimation-tools/hotech-advanced-ct-laser-collimator.html unfortunately I was using a CG5 to hold the 11" SCT and it wasn't stable enough so I stopped using it and moved to a more manageable 80mm APO. I've now bought an EQ6-r so will try the SCT again, I uncovered it the other day and it looks fine, mirror still seems clean and bright My gripe with Bobs knobs is I didn't like the thread on the outside, could be a bit painful on the fingers!

I currently have a Nevada 30A linear supply https://www.nevadaradio.co.uk/product/nevada-ps-30m/ bought from the Nevada shop on ebay. This replaced a Nevada clone switch mode 30A like this https://www.firstlightoptics.com/batteries-powerpacks/nevada-psw-30-25-30a-switch-mode-power-supply.html. I read on here that the linear PSU are more reliable and less likely to cause funny problems with mount motors like runaway slews. At the end of the day its a one off few quid expense so why skimp if its running expensive kit

Added some normal blue, unfortunately I only managed to get 30 mins worth, I'll try to get more to complete the image

Hi I had a celestron CG5 which is the AVX predecessor and has the same mount. I recently bought an EQ6-r which came with the tripod. They are a different fit 😞 I wasn't keen on the metal tripods so I purchased a wooden Berlebach, first time I bought I got the wrong top plate so had to buy the Celestron plate separately , lucky they are interchangeable and it worked great. Then when I got the eq6 I didn't want to get rid of the Berlebach so I bought the eq6 top plate. I now have 3 top plates, photographic, celestron and skywatcher I suggest your options are (IMHO) buy new celestron avx tripod - looks like they are out of stock but maybe order one buy Baader or equivalent adapter make an adapter buy a berlebach, expensive but worth it make some kind of diy pier keep an eye out for a second hand celestron tripod (I sold mine when I bought the berlebach) buy a new eq6-r 🙂 The tripod stability is important, especially on a cg5/avx so make sure you get a good fit. I'd offer to sell my celestron top plate but it fits the berlebach wooden legs While it was fun hypertuning the cg5 and I learnt a lot doing it, changed every bearing, pulled motors and circuit boards out, modded for belt drive (cost wasn't an option, I did it for the challenge) but eventually I decided using it was just masochism so replaced it with the eq6, worth it just for the relative quietness of the motors!

Sorry I couldn't resist the urge 🙂

Hi Dave Thanks for asking. Much as I would like to claim I did this from my backgarden, the following gear was used: Astrodon UV photometric on a moonless night with a 20" Planewave https://en.wikipedia.org/wiki/UBV_photometric_system I'm accessing Australia remotely. I have some time booked to collect some RGB Blue as well, this week weather permitting so I will update as soon as I can CCD: FLI-PL6303E CCD camera QE: 68% Peak Gain: 1.09 Full Well: ~100,000e- Non Anti Blooming Gate (NABG) Dark Current: <.005 e-/pixel/sec. @ -45º C Pixel Size: 9um Square Resolution: 0.81 arc-secs/pixel Sensor: Frontlit Cooling: Set to -30ºC default Array: 3072 by 2048 (6.3 Megapixels) FOV: 27.8 x 41.6 arc-mins Filters: AstroDon Tru-Balance Gen 2 E series Luminance, Red, Green, Blue, 5nm Ha, 5nm SII, 5nm OIII, and AstroDon Johnson/Cousins UvBVRcIc OTA: Planewave 20" (0.51m) CDK Optical Design: Corrected Dall-Kirkham Astrograph Aperture: 508mm Focal Length: 2249 mm F/Ratio: f/6.8 Guiding: Active Guiding Disabled Mount: Planewave Ascension 200HR

Hi Went back to an old image and added more SII, Ha. plus a bit more alternate processing. I plan to try to get some more light blue if I can In the image SII & Ha = Red, OIII = green, UV = blue

I was very tempted by the QHY9s, its a good price now with the extras, the G2 was significantly at the top of the price range with best cooling and the mid priced atik had a deal on filters so I wasn't sure which to go for. I decided you only live once and went with my heart

Hi David I think you had better start looking quick, afaik the 8300 is being discontinued if not already, and I think I bought the last Moravian G2-8300 who I'm told by Zoltan have no more stock, I think I heard the QSI's are also gone ? So if I'm correct that just leaves the Atik383L and QHY9S. I bought now since I didn't want to risk missing out once it starts to get darker

Thanks Kirster Hope so 😀, I've had my eye on one for a while, I contacted Zoltan a few weeks ago and he said it was the last one with the demise of the KAF8300 I spent ages comparing images online from different cameras and decided I liked the KAF8300's the most

I decided I couldn't wait any longer so I've put my order in for what I believe is the last of the Moravian KAF-8300's I decided I would go with the native filter wheel and OAG Now its just waiting to see if the order gets delivered G2-8300-II Moravian Instruments G2-8300 MARK II Monochrome CCD Camera with KAF-8300 CCD EFW-2XS-8 XS External Filter Wheel for Moravian Instruments G2 cameras with 8 positions for 31mm unmounted & 1.25" mounted filters OAG-2-M48 OAG Off Axis Guider Adapter for Moravian Instruments G2 Cameras - M48 threaded version