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Jim Smith

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About Jim Smith

  • Rank
    Star Forming

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  • Gender
    Male
  • Interests
    Astronomy
    Opera
  • Location
    West Herefordshire, UK

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  1. I have a "TS Photoline 80mm f/6 Triplet FPL-53 Super-Apo - Splitable Tube - 2" Crayford" which I bought in 2015 from TS Optics. I also have a HoTech SCA field flattener for it, though this is not a focal reducer. The telescope still operates at a 480mm focal length. Let me know if you're interested and I can give you more details. Jim
  2. Good conditions for trying to improve my lunar imaging last night. SW SkyMax 102 - Altair GPCAM3 178C roi 1520x1024 - 1/125s - best 200 of 5000 in AutoStakkert - tweaked in Affinity Photo
  3. Sigma 120-300mm f/2.8 DG OS HSM S @ 300mm and f/4.0 Nikon D5500 74x30s ISO1600 SW AZ-EQ5 Bortle 4 Affinity Photo, Astroflat Pro, Topaz Denoise
  4. That's an interesting idea. I might try that. EDIT: Just ordered a 105mm to 77mm step down ring from ebay.
  5. I've not done any formal testing but I understand that the sensor in my D5500 is "ISO invariant" so I have been using anything from ISO 200 to 1600 and increasing the exposure in post if necessary. try this... https://dslr-astrophotography.com/iso-dslr-astrophotography/
  6. I would be interested in any findings from your experiments.
  7. Thank you. Yes, it was f/4.0. I had previously done a comparison of f/2.8 and f/4.0 with this lens. Pictures below...everything the same except for focal ratio. I didn't like the asymmetric, blobby stars I get at f/2.8. f/4.0 has diffraction spikes but I don't mind those so much! I raised the exposure of the f/4.0 photo in post to make the comparison easier so it's a bit noisier. No filters...just the D5500 directly on the back of the lens. Clear Outside says I'm Bortle 4. Yes, it was cropped. Third image below shows full field of view captured.
  8. I know that zoom lenses are considered a compromise compared to telescopes. However, I closed the aperture down a bit and got better results than I usually do. Interesting diffraction spikes on the brightest stars. Nikon D5500, Sigma 120-300mm f/2.8 @ 300mm f/4.0, 60x30s, ISO 400 SkyWatcher AZ-EQ5, Affinity Photo, Astroflat Pro, Topaz De-noise
  9. I like... Nightwatch: A Practical Guide to Viewing the Universe by Terence Dickinson
  10. A couple of Messier Object observations from last night. I used an 18mm eyepiece in my 80mm f/6 refractor, giving about 27x magnification. These two clips show pretty much the same views as through the telescope. M1, the Crab Nebula, is only just visible to me eventhough I have quite dark skies. It is very tricky to see in the video clip as well! It is barely visible as a faint smudge in the centre of the video. You may have more luck with the original videos available here...https://www.ishoo.co.uk/messier/ Messier001.mp4 Messier037.mp4
  11. Well spotted! I blame that extra glass of port.
  12. FiveTelescopeTargets.mp4 Five targets from Thursday night with, I think, a view similar to a small telescope. Tweaked in Premiere Pro to get as close as possible to the live view in my 6" field monitor. Sony A7s, Celestron C6, 2 x focal reducers so ~750mm, ~f/5.0, 1/4 second, ISO 51200.
  13. For some time now I have been experimenting with making videos that show various astronomical targets as they appear to the naked eye or through binoculars or small telescopes. I have finally got round to making a home for them and it is here... www.stargazing.camera I hope that it might be useful for anyone just starting out. I have tried to get the videos looking as similar as I can to the live, real-time experience. I will try to add something new every week or two...weather permitting! Any constructive suggestions for improving the site are welcome.
  14. The Seven Sisters is another name for The Pleiades.
  15. Thanks Neil. I haven't done any more quite like that one, but did you see... ...and... Cheers, Jim
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