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Everything posted by sheeprug

  1. Thus far I've been using DSS and photoshop without really thinking too much about what happens to the data. However, with the current rubbish weather it seems a good time to think a bit more about what's happening. My processing chain thus far has been: Stack images using DSS. Open the autosave001.tif file in photoshop Stretch using the levels tool. Convert to 16bit mode using the local adaptation method - default settings. Adjust contrast using the curves tool until it looks good. Bump up the saturation until it looks better. Now since I start off with a 14bit sensor (Canon 750), and each time I double the number of frames I increase the precision by 1 bit, if for example I stack 16 frames the dynamic range is increased by 4 bits so I have a maximum of 18 bits/pixel (though obviously it might not all contain good data). So the question is therefore, do i need modify my processing to ensure I'm not throwing away precision? And if so how? Best, SR
  2. Hi Peter, I got some focusing mechanism spares for my WO FLT110 focuser from William Optics a few months ago. It now works very smoothly, despite what looks like a design flaw in the bearing spacing, so you may be able to restore to full health quite cheaply. The very helpful guy I dealt with was 'Tim', email: marketing@williamoptics.com. Excellent service. Good luck. Best SR. y ..
  3. Hi All, I thought I'd take advantage of an unexpected clear night to have a go at a fainter galaxy on Sunday evening, so here's my first attempt at M101. I used 20x 180s at ISO. 1600, dithered, WO 110mm, un-modded Canon 750d, plus flats and bias. Light pollution from my garden is not too bad. On the whole I'm fairly pleased, especially with the 6 or so smaller galaxies also captured. However, signal to noise is not so good so it's lacking sparkle, and getting rid of a nasty gradient left some artifacts. I'm planning to have another go tomorrow evening, possibly using more and longer subs, and lower ISO, but I'd welcome any further suggestions from you helpful folks. Best, SR.
  4. Thanks for that - interesting. If you get a moment, can you let me know your source please? Thamks, SR
  5. Well I've just popped to the local for a pint. Walking back there's beautiful clear sky overhead between the clouds - of which there are many - all around. It rather reminds me of the old music hall song where the views are splendid, "if it wasn't for the 'ouses in between". It won't be clear enough for a while, so giving up. SR
  6. Similar in East Suffolk. It looks potentially excellent for astro after closing time.... Two weeks ago I'd just about got everything working - I haven't had a chance to try it all since. :-( SR
  7. Interesting, but unfortunately no use to me since the Canon 750D is not included. Anybody know how it might be possible to fine data for it? All I know is it's 12 bits. SR.
  8. Thanks Everybody. Just to round this off, I took out Camera batter to recharge overnight, rechecked everything this morning, connected it all and still had the same problem. Looking at the APT logfile I found lots of the following errors : DBG Error: 0x7, GetPropertyCommand, 0x1000022, 0 and DBG Error: 0x50, GetPropertyCommand, 0x104, 0 I've no idea what these mean - I'll check on the APT forum. However, after a further 30 mins of checking everything again and having a good swear at all the gods I could think of, it suddenly sprang back in to life and is now working again. I've no idea what happened to change this. (Don't you love tracking down intermittent faults!) So I can now run PHD2, EQMOD, CdeC and APT via my new USB hub and 5m cable. I've done my best to break it, but it's now stubbornly working well again. I can now look forward to controlling everything from out of the wind in my relatively warm conservatory instead of risking hypothermia on the patio. The 10/10 cloud cover is a bit of a problem at the moment, but I could do with an early night anyway. Best, SR.
  9. I'v been using APT for a little while now and it's been working well. This with a Canon 750D and a Lenovo laptop with Windows 10. Suddenly it's not working at all well. APT claims it's connected and the camera thinks it's connected (the PC icon is showing on the LCD screen). However, it fails to run any plans, hanging after the first frame, it won't do live view, there's no sound of the mirror operating and at hangs up if I try to stop a plan. Any ideas? I'm assuming I've accidentally changed the configuration somewhere, or possibly a windows update has stuffed something. Grrrr! SR
  10. Oh excellent - that's a useful resource. Thanks, I wasn't aware of that site. Hopefully I won't need it again in the same situation! SR.
  11. It was cold in Suffolk last night. The wind whipped across the patio and cut through clothing like it wasn't there. Had it not been the first night where it was clear and viruses hadn't totally sapped the enthusiasm I'd have sat by the fire and stayed warm. However, duty called and I was set up. M33: 20x 180s at ISO 800, followed by M42: 10x 180s at ISO 400. Then after a half-hearted attempt at M101 the camera battery expired and I gave up. I then consumed far too much sloe gin in an attempt to warm up. Results below. As you can see, I've managed to make an entire galaxy vanish, which I think is pretty impressive. i'm not sure quite what happened there. Presumably after carefully framing it I nudged something. A lesson learned of course, but I have to say it's quite a pleasing picture of a bunch of otherwise unremarkable stars. M42 is much nicer - i'm quite pleased with that - sufficiently so to plan a return to it in the future to do it more justice. Happy days, SR
  12. Clattered by a stinker of a cold/borderline flu type virus effecting each member of the household in turn. On occasions the conditions appear to have been quite good if rather moonlit, but I've not been able to raise my game enough to get the scope out. Better days are ahead - I hope! SR.
  13. Nice - definitely a hint of blue on my Ideapad. What exposure were you using? Presumably '1 hour' is made up of >1 lights. SR.
  14. Thanks everybody. Some good suggestions there. It looks like it's a decision between a new shiny netbook, or a more powerful refurbished deal. I like the Thinkpads suggestion - they were the standard issue business laptops in the company I used to work for, and were good solid machines. SR
  15. Since the demand for laptops in our house outstrips supply, I've been trying to work out what I need to spend to keep everybody happy. Any suggestions on the minimum specs needed to run common astro software programs are? I'm not talking about post processing - that con be done offline - just running PHD2 and APT/BYEOS would be enough. SR.
  16. Nice. Can I ask what equipment you were using? SR.
  17. Thanks for that - definitely looks worth trying, though my PS skills are rather elementary at the moment! SR
  18. Thanks for your comments everybody. I'll have a closer look at everything in the optical path. I fear though, that the Christmas 'interruptions' may have started already, so it may be in a few days! Best, SR.
  19. I took a few images of some star clusters the other night. Below is an enlargement of small section conatining NGC457 after stacking,some stretching and increased saturation. I suspect it's a little over exposed at 60s. I'm wondering though, what is causing the diffraction type effects around the brighter stars? Equipment was WO 110FLT refractor, field flattener, Canon 750d on an HEQ5 guided with PHD2. I'm guessing it's internal reflections in the DSLR since that's the only square item in path, but does anyone have any suggestions? It would be nice to lose it. Best, SR
  20. I tried to image some star clusters last night, with varying success. Partly because I'm new to this game, and also it was freezing and I need to find my duvet jacket! Here is my favourite: NGC 457, with NGC 436 just creeping in at the bottom. I like it, but somehow it doesn't leap out in quite the same way it does visually. Thus I'd be interested in any tips people have for imaging star clusters. I used my un-modded EOS 750d and WO 110 FLT. 15x 60s lights at ISO400 dithered. I used PS to do a little contrast stretching and Astroflat Pro to adjust the gradient a little. Best, SR
  21. Though I can't see this ever becoming a real problem to us really - in fact it's a bit Monty Python: 'he's having a go at the flowers now!'. http://www.independent.co.uk/news/science/glowing-plants-streetlamps-lamps-replacement-new-invention-a8113191.html Happy Xmas to all! SR.
  22. Wow - thanks for that. I'd not realized I'd captured so much colour, and it shows how much of a learning curve I'm on. If you get time it would be really good to understand your work flow. I've been taking a look at some of the available tools such as Astroart, and the gradient removal makes a big difference. Unfortunately the trial version doesn't let me save anything, and I can't get the colour demosaic to work properly. APP and PixInsight trial versions allow saving during the trial period, so I'll take a look there and see if I can do as well. I'd love to hear from anybody who is getting good results from the low cost solutions though. Best, and Happy Xmas to you all, SR.
  23. I Had a go at M33 the other night (Wow - it was cold!!). I managed to get 10x 300s lights, but used dithering in APT/PHD2 rather than taking darks. I'm reasonably pleased with the results in that the guiding seems to be working ok and the focus looks reasonably good, but despite using some simple flats taken the next day with a white shirt over the scope, I still have some gradient left. Bearing in mind the kitty is looking a little empty at the moment (Xmas) so I can't stretch to expensive software, what is the best way to improve this? Try more flats, or is there a good solution based on GIMP? Best, SR.
  24. Thanks. I'm just getting to grips with GIMP, so I'm sure there's much more to discover. I gather a big improvement in the later versions is it processes and handles files in 16 bits. I was using the unstable 2.9.6 version. Best, SR.
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