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  1. Last week
  2. Mizar & Alcor

    100 subs was massive overkill, your images should be effectively noise-free with anything over 50 subs. I had one imaging "expert" berating me for not knowing anything about signal to noise ratio as I didn't take into account the gain in signal to noise with exposure time. Problem with signal to noise increase with exposure time is that the increase is not all that big, and also it flattens off rather quickly especially if your skies are not too good. So in my location the exposure time signal to noise ratio increase flattens off in about 5-minutes meaning that I am getting no (further) S/N ratio increase in the 20-minute exposures I need to take to get faint stuff and the only way I can get the noise down in galaxy or faint nebula images is to take LOTS of subs. The reason why I have often said you need at least 8-hours of good data to get a first class image is that if you take a typical sub length as 10-minutes and then have 50 of them, you're talking just over 8-hours. It only took me about 10 years to work this stuff out Greg P.S. Oh - and by the way - all your 50 subs have to be GOOD. You have to go through every sub and check they are o.k. as I now from experience you can actually see the degradation in the stacked image with just ONE bad sub in 100. P.P.S. And that is also the reason why I run multiple imagers in parallel - I increase the number of subs in a given time by the number of imagers. P.P.P.S. Dithering is essential. So is good image calibration with good flats and bias frames.
  3. Mizar & Alcor

    I can't argue with that. I'm looking at ways to bring down my noise. I also take a vast number of subs, and through my C14 at 4000mm at F11, the tolerances for focus, tracking and guiding can become difficult during dozens of 5 minute exposures ( I bin (throw away) at least half of my subs). I'm going to start using dither more during my imagining runs as well. Ray
  4. Earlier
  5. Mizar & Alcor

    That's just a case of getting the signal to noise ratio up in the first place which means LOTS of subs. When I first started imaging with the original Hyperstar I used to aim for 100 subs (although they were only 1-minute long). I used to get glassy clear completely noiseless images but they didn't go very deep. So it's a trade off. For things like star piccies you don't need a long exposure time - for things like galaxies and nebulae you do - this is one reason I prefer star piccies Greg
  6. Mizar & Alcor

    Very noiseless and smooth Greg. May I ask how you process these to have what appears as zero grain. Ray
  7. Pelican

    Lovely work Prof. Ray
  8. Barnard's "E"

    Both epic work my friend. Ray
  9. Mizar & Alcor

    Mizar & Alcor in Ursa Major taken with the Sky90 array. Greg
  10. Pelican

    That is very nice. Dave.
  11. Barnard's "E"

    And here's a Noel Carboni process of JUST the Sky90 data. Greg
  12. Barnard's "E"

    I combined all my Sky90 data of this object together with the DSS data from the same region. Barnard's "E" is a dark nebula lying close to the star Tarazed. How many stars do you think are in this image?? Registar says there are 165,000 Greg
  13. Pelican

    Playing about on Photoshop 2020 I put together everything I had on the Pelican nebula and then also added DSS data from the same region. Everything stitched together using REGISTAR. Greg
  14. New machine

    Just curves plus Noel's "Enhance DSOs and reduce stars" Greg
  15. New machine

    Love it Greg. What processing do you perform to bring out the dark neb? Ray
  16. New machine

    This is a single frame with the Sky90 array.
  17. New machine

    Managed to get Photoshop and all the associated bits onto a more up to date machine (HP Z600 workstation) as my main computer is slowly losing the plot. Did a test process on some Taurus molecular cloud data - 42 x 20-minute subs. Greg
  18. Tarantula Narrowband

    Been a while since I posted a photo, but having some spare time has allowed me to process some data I have. This was processed mostly in PI and some minor adjustments in PS. Shot at 4000mm, Focal Ratio F11, and probably spent about 50 hours acquiring the correct subs. The total imaging time used is more like 10 hours, but this object sits over the city lights from my observatory and many subs were unusable. C/C's welcome. Ray
  19. The Great Conjunction of the Century

    Great work!!!!!!!!!!!!!! A super record to have. Greg
  20. Lovely work Tim. She looked quite amazing through the eyepiece as well. Naked eye was just as good IMO. Something pretty special about seeing both of those objects so close in the eyepiece. Have a great Xmas my friend. Ray
  21. And, my best effort at the 'Great Conjunction of the Century'. It will still be a good view tomorrow night if one has the opportunity, (and the weather) to have a look. This one is from the 20th. And this is from the 21st. I used the C9.25 with my now old 450da and a 2x barlow lens I fabricated some time back. FOV was about right for this event. Cheers, Tim.
  22. New toy

    I hope it sells quick mate. Need to get some cash back in the bank after paying for the van. Lol. Shane
  23. New toy

    Very cool mate. We love camping. Great time to be selling with no international travel, it will sell extremely quickly. Ray
  24. Time has come to upgrade from the camper trailer to a caravan. Got the new (to us) caravan last Friday, now to sell the camper. Shane
  25. Planetary Debacles

    lol, Probably not the only one. Tim I was using IC Capture. My monochrome camera would freeze after 30 or 40 frames. I tried using firecapture to no avail. I've reinstalled the camera and IC Capture but same problem. I've updated my PC a few months back to Windows 10 on a quad core PC. It is lightning fast, but I have a feeling the camera (which is about 10 years old) is at fault. It is the first time I've tried planetary with this new PC and I really need to update the camera to do the faster PC justice. My 7 position filter wheel which is a nautilus is also rendered useless with Windows 10. Great filter wheel but no drivers seem to work on Windows 10. Interestingly for lurkers that visit here (about 500 per month), I did the get nautilus filter wheel working in The SkyX for about 30 minutes until it crashed TSX and wouldn't go back to a functional state. I still had a good time under the stars. Welcome to AP. Ray
  26. Planetary Debacles

    What program/programs are you using for processing? Seems like I remember hearing about this conundrum before. Tim
  27. Planetary Debacles

    Yep - I thought a monitor had suddenly died - it was actually the VGA splitter cable that fed the monitor, the monitor was fine. I now have a spare monitor on the way - and to top it all off - I didn't actually need the splitter cable. Think senility is setting in. Greg
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