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Maurizio83

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Everything posted by Maurizio83

  1. My last capture of Venus was done over 15 years ago with a 114/900 telescope, in afocal mode, using a 3MP digital camera. It's been ages since that... 🙂 This morning, I tried to capture the planet for the first time with my current equipment. The session was unplanned, but when noticed the planet in the sky, I decided to give it a try. The seeing was moderate, and there were some intermittent haziness, at times quite intense (some videos were discarded due to sudden changes in brightness). Due to the suboptimal seeing conditions, I had difficulty focusing directly on Venus, so I opted for a nearby star. I captured in visible light, using the classic UV/IR block filter. The sun was about to rise, so I quickly experimented with various recording parameters: from nearly 400 fps with an exposure time of 1 ms (limited by the USB connection) and standard gain, to 125 fps with an exposure time of 8 ms and gain set to zero... In the end, after analyzing the results of the various videos, I found that the best outcome was achieved at 250 fps with a 4 ms exposure time, while keeping the gain very low. I avoided multipoint alignment as it created artifacts (perhaps due to the lack of obvious surface details for tracking). I used global alignment, averaging the frames ("average" gave better results compared to the "median" option). Subsequently, I carried out a fairly standard post-processing, as with the other planets. I noticed that by increasing saturation, you can faintly discern some subtle variations in the clouds. I haven't investigated whether this might be possible, maybe they are just artifacts... I have two IR pass filters (one at 685 nm and one at 850 nm) that I could try. I'm not sure if filters specific for Venus (350 nm) are suitable for my color camera. I need to investigate this aspect as well. If you have any comments or suggestions to improve on this subject, they are welcome! 👍 The full-resolution image and detailed shooting/processing information are available here: https://flic.kr/p/2p9p5db
  2. Yes something quite noticeable in many images taken by others as well. For instance, you can see the last image at the bottom of the captures from the 9th Oct on the ALPO-Japan website: https://alpo-j.sakura.ne.jp/kk23/j231009z.htm
  3. Nice image Kostas. It's interesting to notice the same white dot that I captured on the same evening (a few hours later).
  4. New capture of the "poor" side of Jupiter. Over the last 10 days, the seeing hasn't been good (and many evenings it has been cloudy)… But two days ago, I had a few hours of good seeing. Compared to my previous captures, the sky was occasionally a bit hazy (e.g., for 30 sec during the two minutes capture). So, there is a bit more noise than usual since I kept the standard capture parameters (configuration for clear skies). Furthermore, for the first time this year, I had to start dealing with dew on the C8 corrector, as temperatures are now dropping. However, the level of detail seems ok, partly thanks to Jupiter's increasing size. It's interesting to see how the visible details change from one capture to another of the same area. The full-resolution image and detailed shooting/processing information are available here: https://flic.kr/p/2p8F1zq
  5. I had missed your detailed work on Venus. Truly exceptional for its continuity over time (and clearly quality). Your ZWO article is excellent; along with the others as well. My heartfelt congratulations! However, part of the credit for those stunning images certainly goes to your wonderful assistants! 😄
  6. I also tried applying the key steps of my processing standard procedure to your image (Astrosurface + GIMP), and the result seems to be approximately equivalent to yours. Probably, we are following the same steps.
  7. Beautiful image! Have you used the C8? The idea of video derotation is interesting and worth trying! 👍
  8. Very interesting conversation. I also tried experimenting with derotation once last year, but at the time, I wasn't sure if the benefit justified the additional time required. Furthermore, even though the noise was reduced, I wasn't sure that the fine details had actually improved. Maybe the problem from my location is that good seeing images alternate with images with worse seeing, which, when used, reduce the overall quality. Probably I made some mistakes, and I need to learn how to use derotation better. Here you can find the two images for comparison ( 9 images derotated vs the best single ) : https://flic.kr/p/2nXxJhN https://flic.kr/p/2nXqdJs Anyway, I am amazed by the use of a manual Dobsonian. I struggle a lot to find the perfect focus point with a C8 (first on EQ5, now on a fork mount), with sidereal tracking. The idea of doing that while manually tracking a planet is incredible. 😅
  9. The new image clearly appears better to me, particularly sharper and more defined.
  10. Thank you, everyone! Your compliments are very much appreciated! What a coincidence! 👍 Yes, I need to delve a bit deeper into resizing. On one hand, I wouldn't want it to appear too small for those with 4K small monitors (like laptops) or high-resolution smartphones. On the other hand, for those viewing the image on a very large screen (for example, a 30-inch FullHD display), the image might end up looking too soft since very large... +25/30% could indeed be a better compromise.
  11. Hello, after nearly 20 days of stop due to adverse seeing conditions, I managed to capture Jupiter with Io. The GRS was not visible, but there are various interesting details on the NEB/SEB . Any advice on aspects to improve? The full-resolution image and detailed shooting/processing information are available here: https://flic.kr/p/2p6snce
  12. Stunning details, especially on Ganymede, congratulations!
  13. Nice, did you use the 4-inch refractor?
  14. Wonderful picture, congratulations! There are some frames where Europa almost disappears, what happened? Did it go out of the camera's field?
  15. Highly detailed image. The animation gives the impression of being even more detailed at certain moments. Beautiful!
  16. Even only with wavelets and a few other tools it is already possible to ruin the image. So you've used these "few" tools well! Maybe the problem is the USB2 port. I would try using a short cable and a USB3 port at home to see if you can achieve high fps in line with your camera's specifications. APO refractors are probably not widely used for high-resolution photography, not because of limitations in their optics (more likely the opposite), but because it's challenging to handle such kind of telescopes with a large diameter. In the end, diameter is a fundamental variable for achieving the maximum resolution. Yes, the definition of mount stability differs significantly between DSO and high-resolution imaging. For several years, I used a C8 on an EQ5/CG5 mount (which is less capable than yours), and although it wasn't rock-solid, it worked reasonably well for planetary imaging.
  17. Hi Chris, your images are already good. Jupiter, in particular, came out very well, and the processing looks quite natural, which I like. You should try to see if you can capture at more than 15 frames per second so that you can be more selective in the percentage of frames to stack. I'm not sure if a Mak 127 would make a significant difference compared to your refractor, which seems to be a good optic. Since you have an HEQ5 available, you might consider an 8-inch or perhaps even something around 10 inch, like a C9.25. That's when you would see a notable increase in achievable resolution. Anyway, I would continue practicing with your current setup, as it can still produce beautiful images!
  18. Very nice images. Why does the central one appear to have a haze/fog around the rings?
  19. Hi, a few nights ago, I experimented with a new RGB balance parameters configuration in SharpCap. The final result seems slightly improved compared to the previous images. What do you think? Do the colors look okay to you? The seeing was good, and it appears to be my best Jupiter of the year so far. Of course, as Jupiter's diameter increases, the achievable resolution improves! 😄 The full-resolution image and detailed shooting/processing information are available here: https://flic.kr/p/2p3pp2b
  20. The first Jupiter is very detailed, beautiful!
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