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BrendanC

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Everything posted by BrendanC

  1. I have to say, the idea of a reducer somehow widening a field of view while keeping the aperture the same size has never made sense to me. I mean, I know it does. I just don't for the life of me understand how.
  2. That's exactly the route I took for exactly that reason, and my guiding is fine with a guide scope.
  3. Agreed on all counts (including giving the laser to the cat!). I was struggling, got a Concenter, sorted the secondary, never touch it now. Just a quick check with the Cheshire to get the primary centred. The Concenter was more than I wanted to pay for a pretty much one-off fix, but I would still be getting frustrated with collimation if I hadn't bought one.
  4. Thanks - I use APT which doesn't have a mosaic feature, sadly. I sorted it last night though, got to 89.7 degrees which I think is close enough!
  5. Hey @vlaiv to the rescue again! That's exactly what I'm going to do. Take one shot, plate solve, show in Stellarium, rotate, repeat until it's at 90 degrees. I was so certain I had the camera right before but obviously not. A check beforehand is definitely the right way to do this, especially with mosaics. And that's exactly why I did a trial run first. The geometry of RA, Dec and a camera beat me I'm afraid... Thanks again.
  6. Me again. A sudden thought: when the camera is supposed to be rotated by 90 degrees, that's not at 90 degrees to the scope, is it? It's at 90 degrees to the horizon. So I need to rake into account the angle of the scope - which, at 26 degrees, is about right for the veil nebula - and then rotate the camera by 64 degrees. I've done mosaics twice before, not had this problem, and I can only assume it was blind luck that they worked out. If someone could confirm I'm right about this, I'll have learned something! No such thing as failure, just a lesson learned and all that...
  7. OK so I took a different approach - plate solved an image in APT and then used the Show function to see it in Stellarium. This shows that the image was at 64 degrees, not 90 degrees. So my very first thought, that it's just the camera rotation, was right. But the camera looked to be exactly at 90 degrees. I cannot figure out for the life of me how I managed to be 26 degrees out. Tonight I'm going to take just one shot, then do the same check: show the result in Stellarium and make sure I've got the right place and the right rotation. Weird.
  8. So, last night I did a quick test to check my veil nebula mosaic coordinates and camera orientation were right. It came out like this, after running it through ICE... According to Telescopius, which I used to create the coordinates, it should look like this: / Now, if I go through Stellarium and use the exact same coordinates, with the camera rotated by 90 degrees (which is what Telescopius says this would be), it works perfectly ie I can do a screen grab of the camera's FOV, copy and paste it into Photoshop, and manually rebuild the mosaic and it looks just like the above graphic. I have literally spent all afternoon scratching my head to figure out what's wrong here. The coordinates are right, I'm sure. The camera is rotated by 90 degrees. So why are the subs in the mosaic all out? Is it really a camera rotation issue? I've been through everything several times and that's all I can think has gone wrong here. But I just don't know for sure. I'll be running it again tonight. I've redone this in Telescopius and rebuilt all the plans, but I don't see anything radically different and I don't expect a radically different result tomorrow. Any more suggestions? Thanks, Brendan
  9. Finally managed to get the imaging from the eclipse sorted.
  10. Hi all, I just watched this. Highly recommended! https://www.netflix.com/gb/title/81343342
  11. Hi all, Just thought I'd share some DIY. I've had a couple of occasions where I got big light spikes across images, probably due to internal reflections, which flocking might fix. I didn't want to flock the whole scope, which would involve taking it apart. Nor did I want to permanently change it, in case I wanted to reverse the procedure. So, I got some magnetic paper, stuck some of the 'fluffy' side of some old velcro I had lying about on it, and then inserted that behind the focus tube simply by rolling it up, putting it between the spider vanes, and letting it unfurl and stick to the scope. Looks pretty good, comes out and back in very easily. Not tested it yet, but I thought I'd share it.
  12. Personally I'd sell the wife and invest the money in some really tasty astro equipment. The kids too if you have any. But keep the dog.
  13. The best thing I ever did for collimation was to replace the horrible screws on the secondary with some decent thumb screws. I got these but they're currently out of stock (isn't everything?): https://www.amazon.co.uk/Set-Thumbscrews-Secondary-Mirror-Collimation/dp/B00UJUOXA4 You might have more luck at Bob's Knobs - see http://www.bobsknobs.com/ They're so very much easier to manipulate because you can move more than one at a time without worrying about Allen keys falling out or dropping onto the primary etc. Then yes, as others have said, use a collimation cap and/or a Cheshire, not a laser. And follow this guide: https://www.astro-baby.com/astrobaby/help/collimation-guide-newtonian-reflector/ Good luck. I hate collimating. Or, rather, I hated collimating until I also got a Concenter which helped sort out the secondary, and now I just have a quick check with the Cheshire to align the primary - about a minute, and I'm done. Very occasionally I'll check the secondary with the Concenter but it's always spot on. It was more money than I wanted to spend, but I'm glad I spent it. I also developed a solution using my mobile phone in case you'd like to give that a go, see https://stargazerslounge.com/topic/360299-interesting-collimation-technique/ Actually, come to think of it, I still hate collimating.
  14. It's a big step, but the right one. I was very reluctant to take it because I'd become very used to using the handset as a relay with my old AZ mount. Then I got a second-hand NEQ6 (funnily enough through this forum) and wanted to do the same, but whenever I flashed the handset to be in relay mode, it wouldn't have it. Wouldn't work in PC Direct mode either (although relay mode is supposed to be better). Then, when I got an EQDIR cable, that didn't work either, with the default Sky-Watcher drivers. Then, on advice from this forum, I went the EQMOD route, instead of the Sky-Watcher drivers, and never looked back. EQDIR and EQMOD is absolutely rock-solid, and you can just let it all work in the background with no problems. So yes, forget the handset, get the EQDir cable, set up EQMOD via that link I shared (you don't need Stellarium and Stellariumscope but they come in handy sometimes - even though Stellarium now supports ASCOM, I think Stellariumscope offers a quick, easy way to align your scope if you're not plate-solving), and you won't look back.
  15. Agree with the above. I could not get my NEQ6 handset to play ball so took the the plunge with EQDirect and never looked back. This tutorial is excellent: https://www.lightvortexastronomy.com/tutorial-setting-up-an-equatorial-mount-on-ascom-with-eqmod-stellarium-and-cartes-du-ciel.html
  16. I'll take that as a massive compliment, thank you.
  17. Hi all, I recently discovered that I live very close to where an eminent astronomer used to live, called William Rutter Dawes. If the surname's familiar, that's because he is the originator of the Dawes Limit, used to determine the practical limit on resolving power for a telescope. He also has a crater named after him on the Moon, also one of Saturn's rings, and received the RSA Gold Medal in 1855. So, quite a significant figure! I was intrigued when I discovered that the telescope that he had in his observatory (the hole through which it poked is still visible in aerial shots of the house) is still in use at Cambridge University. So, I attended one of their night-time lectures and by special permission, was able to see the scope and take some snaps. It's called the Thorrowgood scope and you can read more about it here: https://www.ast.cam.ac.uk/about/thorrowgood.telescope And here are some of the shots I took! Given that my house dates back to 1695 I think it's a virtual certainty that Dawes must have at least walked past it on many occasions, and who knows, might even have been in it! And here I am, 150 years later, practising astronomy (in my own small way) about a minute's walk away. Just thought you might find this of interest. I find it quite inspiring! Cheers, Brendan
  18. Thanks! One of the benefits of a Newt with those diffraction spikes.
  19. Hi all, Pleased that I managed to get enough data between the clouds and before astro darkness for this one! • 4:22 hours of integration at ISO800 from 43x240s + 30x180s subs • Bortle 4 sky, no Moon • Calibration: 25 flats, 25 dark flats, 50 darks • Hardware: Sky-Watcher 130PDS scope (F5), Sky-Watcher NEQ6 mount, Canon EOS1000D DSLR camera with IR filter removed, Sky-Watcher 0.9x coma corrector, Datyson T7C guide camera, Angel Eyes 50mm guide scope • Software: polar alignment with SharpCap Pro, guiding with PHD2, capture with Astrophotography Tool (APT), stacking with Deep Sky Stacker (DSS), post-processing with StarTools, Photoshop CS2, Affinity Photo and Topaz Denoise AI
  20. Thanks! When I say DSLR I mean with a telescope attached, obvs.
  21. Hi all, Not posted an image in this part of the forum before, so here goes...! Two versions, one 2x2 binned and one unbinned - I like to do this with shots that have a relatively small central object to get an idea of the object and its surroundings too. Details are: • 5:08 hours of integration at ISO800 from 224x60s + 21x240s subs • Bortle 4 sky, Moon at average 36% phase, 44° height • Calibration: 25 flats, 25 dark flats, 50 darks • Hardware: Sky-Watcher 130PDS scope (F5), Sky-Watcher NEQ6 mount, Canon EOS1000D DSLR camera with IR filter removed, Sky-Watcher 0.9x coma corrector, Datyson T7C guide camera, Angel Eyes 50mm guide scope • Software: polar alignment with SharpCap Pro, guiding with PHD2, capture with Astrophotography Tool (APT), stacking with Deep Sky Stacker (DSS), post-processing with StarTools, Photoshop CS2, Affinity Photo and Topaz Denoise AI Thanks! Brendan
  22. Seeing the Moon for the first time through a telescope is better than seeing the Moon for the second time through a telescope!
  23. I'm also based in Bucks! Welcome.
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