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Spaced Out

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About Spaced Out

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  1. Baader MPCC MKIII connection

    Just a quick update on this. After my first ever telescope collimation (which was a right old hassle, but that's another story altogether !) I managed to test the MPCC again the other night, very briefly between clouds with just a few short high ISO test shots to assess the stars. As folk had suggested, getting the scope in better collimation has improved things, those triangular shaped stars on the edges are now round. However, when viewed at 100% they are still a little 'eggy' in the corners. Maybe achieving perfect round stars into the corners isn’t actually possible with a crop sensor DSLR and this is as good as it gets ? Maybe my collimation and spacing still isn’t perfect ? Anyway, it’s not bad for now and this will do me. I can’t face any more hours of faffing on with collimation and spacing !
  2. Thanks Steve, that looks interesting and certainly worth a try. I will download EZPlanetary and try the settings you suggest to see if I can get similar results.
  3. Thanks, I already had it set to 2x2 mean for this test and these were the results. When I use no NR I get grey image with vertical banding that changes in brightness from frame to frame, when I use 2x2 mean I get the image above constant dark with the white dots and when I use 3x3 median I get a noisy looking snow storm ! I was testing it indoors in the afternoon so camera was on the guide scope with the cap on and covered in a blanket to block out light. I knew it had these white dots from a very quick look the night before, I was just trying to clean them up before a proper test at night. The focus had been left where I had it focussed the night before on a star so I think it was roughly in focus. Did your asi120 show white dots when out of focus then that cleared up when focussed ? No matter what I do the white dots are consistent and don't move so I'm guessing these are hot/stuck pixels ? I tried using it last night with PHD, didn't use bad pixel map or darks library, I just put up with the static white dots. Didn't get far at all because it kept crashing and saying it couldn't connect to the camera again, another problem to sort out ! Perhaps I need to look at the camera settings separately from PHD ? I haven't downloaded the software for that yet, I just chucked it onto the guide scope as it came and was shocked that the two functions that are supposed to improve your guiding image have made it worse.
  4. Thanks for the reply. Before this I was using a webcam that had 2 hot pixels, I used the bad pixel map and they vanished leaving a dark sky and the odd star visible. I was quite shocked that when I used the bad pixel map with this camera I got a load of snow ! Is that just normal then ? Any idea how I can improve this ?
  5. Hi all Novice alert ! I’ve just bought a 2nd hand QHY5L-II-C to use for autoguiding with PHD2. I plugged it in today for a quick test and I am little disappointed that it seems to have quite a few hot/stuck pixels. I thought that the dark library or bad pixel map functions in PHD would solve this problem and clean up the image a bit, but they both seem to make things a lot worse. The results don’t seem at all smooth and they look more like a blizzard of white dots, is that normal ? I’m a complete beginner with this so I’m sure I’ve probably done something stupid to get these results. I did follow the PHD manual instructions tho (I think). Any thoughts/advice on where I am going wrong ?
  6. Baader MPCC MKIII connection

    Yeah I'm wondering if my expectations were maybe too high. Maybe wall to wall round stars on a crop sensor DSLR isn't possible then. I've not tested it with my full frame DSLR because I assumed the vignetting would be worse with a T2 adaptor and FF. I used callipers to measure my cheap ebay t ring and it was 9.9mm thick, I used the spacers and after lots of test shots at different spacings I decided 1.6mm of spacers worked best with my setup. At the end of the day this only cost me a further £16, so much cheaper than buying the Baader stuff. I'm happy that the MPCC massively improves bad coma on my 130PDS even if it's not perfect to the edges. The remaining coma on this test shot below seems uneven and more towards the bottom right, so maybe collimating the scope (which does need doing) will help a little bit too ? As mentioned, in most cases there would likely be some cropping involved too, so maybe this isn’t as big an issue as I think ? Next job is to try and tackle the spacing of the M48 ring I’ve bought, I’m wondering if a pair of scissors and some old plastic milk cartons might work ? Test shot is MPCC + 9.9mm t-ring + 1.6mm spacers. Canon 7D, 5 minutes, ISO 800
  7. Baader MPCC MKIII connection

    Yeah it wasn't bad at all with the just the t ring and no spacers tbh. However, on close inspection there was still a bit of coma around the edges and corners. In my case adding 1.6mm of spacers seemed to reduce this. I still have some minor coma with the spacers fitted but it seems uneven (more along the bottom edge) and I suspect that may be down to poor collimation. I'd love to eventually get nice round stars corner to corner but I don't know if that is a realistic expectation or not ?
  8. Coma, mirror issue or poor collimation ?

    Thanks everyone for your feedback and those positive comments too ! I hope I’m not far off with this then, I’m getting the feeling (and hoping) that the corners, particularly at the bottom, are more likely to do with poor collimation than the coma corrector. I did the star test without the CC fitted and that did suggest it was slightly out. I will attempt to collimate the telescope for the first time today and then test it again on the next clear night.
  9. Baader MPCC MKIII connection

    Don’t be put off, it doesn’t have to be that expensive to get you started. I just bought a cheap ebay T2 ring and the Baader spacers suggested on this thread, the spacers were about £12 delivered and ring was about £4. http://www.ebay.co.uk/itm/Lens-Adapter-For-T2-Lens-to-Canon-EOS-EF-Mount-DSLR-Camera-1000D-600D-5D-DC310-/371784024250?hash=item56900e00ba:g:oLoAAOSw~y9ZAseh https://www.firstlightoptics.com/adapters/baader-t2-delrin-spacer-ring-set.html The results are way better than without the MPCC, you can see my first test shot with this setup HERE. It’s not absolutely perfect, but I think the minor imperfections are probably due to poor collimation. I will be sorting that out and then testing it again.
  10. Baader MPCC MKIII connection

    Hi Everyone Thanks for all of your input on this. I eventually bought a T2 ring and the delrin spacers and also the Skywatcher M48 ring. I am setting the MPCC up with the T2 ring first as that seems easier and more flexible in terms of spacing. Once I am happy with that and using it I will start trying to set it up with the M48 ring. Seems like spacing is critical and there are less options for the M48 ring so I thought I’d take the easy T2 option first and treat it as a learning experience before trying to tackle the M48. After weeks of cloud, last night was clear, so I set it up the best I could with the T2 ring and spacers, I feel I’ve made some good progress but I still have a small problem with stars streaking which may not be coma ! I’ve just started a new thread on that issue HERE.
  11. Hi all I’m a total newbie just starting to learn about telescopes/imaging. Last night I attempted to set up my Baader MPCC MKIII with the 130PDS. I tried a number of different spacer options with the T2 ring and compared the test images. Eventually I decided that 1.6mm spacing gave me the best results. However, even with the spacing as good as I could get it there seems to be star streaking around the corners and edges. The distribution of this (coma ?) isn’t even and it seems worse in the bottom corners, I also noticed the stars look a little bit triangular, which I remembered reading somewhere indicated maybe a mirror pinching issue ? With this in mind I did a quick star test for collimation and it seems the scope is slightly out and in need of collimation (a scary task that I need to learn how to tackle !). SO...... my question is this.... Do you think those stars around the edge are still showing coma or does it look more like poor collimation or a pinched mirror issue ? Or maybe I am just expecting too much ? I’m hoping to try collimating the scope today or tomorrow using Astro Babys guide, fingers crossed that may help. I’m still pretty pleased with the MPCC, it's so much better than without, just a bit frustrating I can’t get it perfect to the edges ! Thanks in advance for any advice you can offer.
  12. Baader MPCC MKIII connection

    Hmmm..... If I end up spending £95 on that to save myself some hassle then then there BETTER BE no problems !
  13. Baader MPCC MKIII connection

    OK thanks, a lot of dosh but maybe the easiest option then. I was moaning on about paying £55 for the baader t ring but seems to get it all working right it will cost me double that ! Is the skywatcher M48 ring with a filter ring addition that you mentioned earlier an accurate and easy to make alternative ?
  14. Baader MPCC MKIII connection

    Thanks I was getting the impression from what people were saying that M48 t ring was the way to go with this ?
  15. Baader MPCC MKIII connection

    Ok, having read all of the above I'm still left scratching my head a little bit. I'm a complete novice just starting up so please don't shoot me down if any of this sounds stupid ! I've bought this baader MPCC but it seems there really isn't a straightforward way to bung it onto my Skywatcher 130 PDS without faffing around with various spacers/filters etc ? Even the expensive Baader stuff advertised for the job results in the wrong measurements it seems ? If baader stuff won’t just plug in then I'll buy a cheaper M48 T ring and spacers etc and then try to put them together somehow to get the correct measurements. Just wondering from other peoples experiences how easy is this to achieve ? I'm thinking I'll just buy a t ring and take it from there. If I have the t ring dimensions will it then be fairly straightforward to find spacers or filter rings of the correct measurement to just plug in and make it all work ? Or is it likely that I will have to start getting bits machined/cut to fit ? Thank in advance for any more advice on this one !
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