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alexbb

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alexbb last won the day on September 12 2018

alexbb had the most liked content!

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About alexbb

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    Sub Dwarf

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    Male
  • Location
    Romania, 45N
  1. alexbb

    Under Rated Images

    As a side thought, I find the timing of posting very important. Holidays, weekend, night, clear everywhere, moon, etc. People won't spend time online when they've something else to do. I know that I asked specifically for suggestions sometimes and received none. Other times, I get feedback even if I don't ask specifically for it. Post the best image just after an eclipse and it will be much less noticed. There are studies for when you should post on Facebook to get the most views/reactions, when news should be published to reach more people, what type of content at which hours, etc. Maybe do a research on this topic too to get another kind of answers.
  2. This one https://www.firstlightoptics.com/adapters/lynx-astro-m48-adapter-for-sky-watcher-72ed.html Indeed, that should allow for a more inward focusing.
  3. Hello, Steve! Maybe I pixel-peep, but the 0.85x SkyWatcher reducer/flattener and the OVL non reducing flattener don't give perfect results around corners with APS-C and 4/3" format sensors at the expected 55mm backfocus distance. I found that the image quality improves at ~60mm, but with the mentioned flatteners, at 60mm, you're just at the focus limit and stars are still not perfectly round at corners. Increase the backfocus distance more, and you won't be able to focus anymore. Here's an image shot with a Canon 550D (APS-C sized sensor) at 55mm backfocus (just the M48 -> EOS adapter used) and the SkyWatcher flattener. And below an image shot with the same flattener, but this time with a "spacer" about 3mm wide. The stars have a better shape at corners, though not perfect. And here's an image shot with an ASI1600 (4/3" sized sensor) at ~60mm backfocus, same flattener. The sensor is smaller, but the pixels are smaller too so they should emphasize any distortion. How good is good enough? That depends on each person. I don't think there's anything wrong with the optics, just that the backfocus distance should be more than 60mm and there's not enough focus travel distance to play with with those flatteners. One day I will try the TS as it seems that one is (or can be) fully inserted in the drawtube. Of course, I will post the results. Hope this is useful! Alex
  4. I have updated the original post with the final composition. Thanks for watching!
  5. Final one. Please click on the image to watch it in full resolution and see its acquisition details too.
  6. New version. Is this better?
  7. Sometimes less is more, but some other times more is less. Spend wisely and enjoy! Not very helpful, I know.
  8. Thank you all very much! The sensor on the 183mm certainly looks appealing as it has AR coatings. That's something my camera lacks and you can see easily. If you're after mosaics, maybe a larger sensor would suit your needs better. Instead of 3 panels with the smaller sensor, you could cover with just 2 with an ASI1600, QHY163 or Atik Horizon.
  9. This an ongoing project on multiple years. Last season I shot a wider Ha - OIII composition with a shorter Canon lens. This season, yesterday night, I managed to shoot through the Esprit 80 the last G panel I needed for an RGB (no L yet) rendition. I want to create an HaRGB image of everything, I don't think I will bother with the OIII too. During this weekend I will process all the panels, but for this evening I prepared a quick version of the Horsey, Flame and the small butterfly between. Which are your views on improving the image? I believe I have some shorter subs that I can use to separate Alnitak from its companion, but I don't want to fall into a pitfall of compressing the dynamic range very much. After all, the bright stars are really bright. Here's the image: Thank you in advance! Alex Edit: Final composition:
  10. alexbb

    EQ6-r pro vs CEM60

    As Vlaiv said above, you might need to pay more attention to balancing and guide settings. Or consider servicing your mount. OTOH, SkyWatcher mounts performance is know to vary form one to another very much. Whilst Vlaiv's HEQ5 guides at 0.5" with fine tuning, my AZ-EQ5 was "tuned" by DarkFrame and I got back a mount with ~70" periodic error. I can barely get to 1.2" RMS on short periods. Last night it was guiding 1.8"-2.0" RMS. Personally, my greatest fear about a 10" newton is the wind. But then, most probably, the seeing would be bad as well.
  11. alexbb

    EQ6-r pro vs CEM60

    I don't think it's a bad idea Please let us know how it performs. Clear skies!
  12. alexbb

    EQ6-r pro vs CEM60

    SkyWatcher say that the 250 DS is 14.38kg. https://www.skywatcher.com/product/bkp-250-ds/ Indeed, you'll need to add to that.
  13. alexbb

    EQ6-r pro vs CEM60

    I own an EQ6-R and out of the box it guides 0.5"-0.8" usually, depending on the declination. Sometimes it's even better/worse (0.4" or 0.9"), depending on seeing too. I've a few astro friends who own CEM60s. Some with encoders, some not. They report the guiding in between 0.4"-0.7" usually. I wouldn't really say the CEM60 provides x2-3 the performance. But without encoders, the price is less than 50% higher for the CEM60 compared to the EQ6-R. In any case, some other pros for the CEM60: - much lighter compared to the EQ6-R. ~12kg vs ~17kg - has a native ASCOM driver, whilst with the SkyWatchers you need to use EQASCOM. Some people really like EQASCOM, but I found polar alignment without seeing Polaris cumbersome compared to the handset routine. - USB hub build into the mount (2.0 only though and not powered) - cables ran through the mount's head - slightly higher payload
  14. alexbb

    M51 2 years worth of data

    Nice! That's a lot of detail for the little scope!
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