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maxchess

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About maxchess

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    Guildford, UK
  1. Ok, as i write i am finally guiding using the 90mm fl500mm frac on my C8 with the Orion SSAG camera. I am using the internal guider with Indi Ekos on a Rasperry Pi3+. This allows me to sit inside and track progress via VNC on a tablet or laptop, All seems fine and the camera can find stars with the gain turned up to 70 out of 100 on the SSAG. Seems to be keeping within the 2 arcseconds limit most of the time, but my Polar Alignment probably needs some work. I also think I am guiding at the limit of my EQ5-pro weight. Currently the total weight of the two scopes and the cameras etc is 10.2 kg. I think the max for imaging is 11 kg. I am only doing 200 sec exposures because its M2 and quite bright, but the surrounding stars look sharp.
  2. I followed that advice and now get the prisim fully iluminated, by day I can see distant trees clearly full frame in the oag guide camera and the main camera image seems unaffected. The problem is that at night the very few available stars are too dim to guide on. The Orion SSAG and the ZWO ASI 178MC do not seem sensative enough despite adjusting gain, applying darks and various transformations. I can guide ok with a 50mm guidescope but not with the oag. Everything I have read elsewhere confirms this view and while it might occasionally possible to use a cheaper camera , to get reliable OAG guiding at long focal length you need a very sensitive guide camera, like the lodestarx2. So I am going to plan B and mounting a 90mm fl500mm frac on my C8 and try to guide with that. Should be a lot more photons.
  3. Alacant, I notice from another thread that you use a monochrome Datyson T7 with your OAG. Would that be any better than my Orion SSAG or ASI 178MC? its a lot cheaper than a Loadstar.
  4. The Celestron OAG I use has a helical focuser on the guide camera fitting, so achieving focus was not the issue. I focused during the day as you suggest and I could get focus when pointed a a bright star. I used Altair, but when the scope was pointing at my intended real target the potential guide stars were too feint. I could see them, but they were very dim and lost amongst noise of high gain. I tried lots of settings for gain and various transformations available in EKOS and I used darks. This lark is difficult enough already and using a poor camera just makes it harder. It all worked fine through a 50mm mini scope, just not the tiny prisim of an OAG at extended focal length.
  5. If you try using the QHY5L-II-C on an OAG you may have problems. I have been trying to get my OAG to work on a Celestron C8 + .63 reducer, using the Orion SSAG mono camera. I had guiding working fine through a 50mm mini scope on 90mm frac, but the OAG uses a prism and gives you a tiny fraction of the light coming through the scope. The result is that with the wrong camera the stars are very few and very feint and not good enough for guiding. Many of those who use OAGs successfully do so with a lodestar, which is mono and very sensitive (and expensive). You camera is also the colour version which reduces its sensitivity further. As a result of my experiences I am going to mount a 90mm scope on my C8 and see if that works, while I save up for a Lodestar. I would be very interested to hear if you get the OAG with a QHY5L-II-C to work. I might just be me.
  6. I used a combination of all the advice above and made progress. By adjusting the prism I got the guide scope fully illuminated and increasing the gain gave brighter images. However I am finding that with my two cameras I only get a few indistinct stars that my software won't guide on. I am using the INDY EKOS internal guider which worked well when I was guiding a 90mm scope with the Orion SSAG. I am coming to the conclusion, after my own experience and reading various forums that I need a better guide camera to guide using an OAG, something like a lodestar. (maybe I should try PHD2, but the stars are so indistinct, even using darks that I am not optimistic) My next step is to try guiding through the 90mm scope (f=500) mounted on top of the C8. I have read that I might get "Flexure" but I am using a Focal reducer with only a C8 so I hope it will not be a problem. The mounting uses what looks like very substantial rings from ADM. Now waiting for a clear night.
  7. OK tried to test the new set up in between the cloud with no spacers in the OAG having achieved daylight parfocal as described before. . After focusing tried to image M27 Dumbell Neb. The DLSR bit worked with only mild vignetting , but my guide cameras could not find any stars. Only had a short time to try swapping guide cameras and playing with settings. Wondering if Orion SSAG and the ZWO ASI 178MC just not sensitive enough.
  8. My image train is: C8 - F Reducer - OAG - Spacer -DSLR. and OAG - spacer - guide camera ZWO ASI 178MC Does anyone have this combination working without vignetting, if so what is the spacing? I used the 11mm spacer to the DLSR and 6mm to guide camera as recommended in the OAG manual. I can get both the DSLR and guide camera in focus, but after trying last night I found that both cameras have vignetting. On closer reading I noticed that the Celestron OAG instruction book does not include any mention of use with a FR. Odd really since I would guess that most imagers use one with an SCT. Checking round the forums I find that this is a common problem especially with larger Edge SCTs. However I have the basic 8" SCT. It is also clear that the OAG is quite fat and places the camera further away from the telescope back than my standard 2" nosepiece. So I have just done a daylight test with no spacers or nosepieces on either camera and they both focus and it looks like vignetting has disappeared on the DSLR and is much reduced on the guide camera with increased image brightness, So I will test it on the next cloudiness night. However I would still like to hear from anyone who has the C8/FR/OAG/DSLR combo working Max
  9. Hi, I am setting up the Celestron OAG (93648) but get severe vignetting on the guide camera. The scope is a standard Celestron 8" SCT with a 6.3 focal reducer. The main camera is a Canon 450D (APS). I have two camera I have tried as guide cameras. The Orion SSAG and the ZWO ASI 178MC which I already have. I am trying a daytime setup using a distant tree. I can get both the canon 450d and either guide camera both in focus, but the guide image shows severe vignetting, such that I get a moon shape half image, but I can still see the tree. Is this normal or should I expect a full image? I have not tried adjusting the prism depth as the manual cautions against it and I am worried about intruding into the main image space. Any ideas., or will it work like this. I would rather not buy yet another guide camera.
  10. Ok all that is really useful input and I guess there is no one size fits all. But is the ED APO 102mm “good quality” and what does that mean? I would hope not to buy another scope after my next purchase but try and improve my technique through guiding, better focus, filters etc. Then maybe in a years time go for a dedicated Astro camera. With this scope will I be building on a firm foundation or will I be wishing I had bought something else.
  11. Hi I am looking to upgrade my scope and I am tempted by the ES 120. I intend to use it for Astrophotography. I currently have a cheap Aquilla frac 90mm f5 fl 500, on a Heq 5 pro, mounted on a steel pier set in concrete. I use a Canon 450d but will upgrade later. The Aquilla cost £175 and I have got some great results, but I suspect/hope upgrading will give me big improvements. I also have a C8. My reasoning went Sw80ed great reviews, but doublet, ES80ED is triplet, but for a little more I could get the ES120 essential triplet. 1.6 more light. But it's f7 a bit slow and it's fl is 714, maybe a bit tight FOV? Any views!, plus what difference will I notice?
  12. maxchess

    absolutely gutted, what now!!

    What replacement camera depends on how far you have got in your learning. Also you don’ say what scope you have. But if you look on astrobin.com you can see what is achieveable with different combinations of kit. I am amazed what some have achieved with the basics: eq mount + 80ed + modest DLSR. In particular there are great images taken with Canon 450ds unmodified and these great workhorses can be picked up quite cheeply second hand.
  13. M81 Bodes Galaxy and M82 Cigar galaxy. Taken last night 23rd April despite a bright moon. 120 x 60 sec lights, 40 darks. No bias or flats as I'm having a bit of problem with my flats at present, they seem to make things worse not better. Taken with Canon 1100d unmodified with a Celestron C8 on an HEQ5-pro. Processed in DSS and Star Wars (Sorry Star Tools). The Star Wars connection?, well you can see that M82 is better illuminated while M81 is on the Dark side. It was reported that a supernova was observed in Bode’s Galaxy in 1993, however it is much more likely that M81 was the location of Alderaan. destroyed by the Death star in the first 1977 movie and we viewed this event 12 ish million years later given that M81 is 11.8 million light years from Earth. If this sounds a bit far fetched remember that the story was set "A long time ago in a galaxy far, far away" so it sort of fits. If you don't believe this then all I can say is that "I find you lack of faith disturbing"
  14. Which OTA is it?, Can you provide a link to the specs? Also, how much does it weigh and would it be appropriate for an HEQ5_pro. Finally how easy would it be to fit a vixen rail for the aforementioned mount. Thanks
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