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FaDG

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About FaDG

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    Star Forming

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    Rome, Italy
  1. A lot of data in there for the short integrato time! What is the used setup and where did you shoot from?
  2. Out of all issues you have, this is one you don't! After the polar alignment process, recent SynScan versions provide you with the estimated polar error in azimuth and elevation, and can even help you correct them if you don't have polaris view. But for now forget that. You can happily live with the 12 arcmins error, so press enter and just go on. Thumbs up. Fabio
  3. Cheers Dave, your stars are indeed better. The coma issue seems solved, but there is a slight horizontal elongation. Guiding or a tad of astigmatism?
  4. This is an example, shot with the above mentioned setup and an IDAS V4. I still get a wee of deformation on the stars in the extreme right side, but I can definitely live with it! And the Field of View at 320mm is gorgeous.
  5. No experience with the Esprit 80, but I have TWO (*) TS Photoline 0,79 reducers (ok, I have the Tecnosky version, but it's exactly the same). Using it on a Sharpstar 72ED (same OTA as TS Photoline 72/400 f5.5), I can confirm that it's great on an APS-C chip. WARNING: I spent weeks to tweak the chip to reducer spacing, getting it right to 0.1 mm, and now always work at f4.5, and despite the T2 (M42) adapter, vignetting is not a big deal, can be corrected with good flats @Ollyis right in that, at such an extreme f ratio, tolerances are very tight, and even the slightest tilt (in my case it was the camera sensor, but it can be the focuser or decollimation) will drive you mad. Finally I purchased a tilt adapter. Furthermore, major temperature changes need to be compensate by refocusing. But once you get the hold of it, it's just like magic! So, I can't say how it will perform on the Esprit, and you'll have to adapt backfocus, but if you are ready to stir the hornet's nest and survive, it could turn out great! Fabio (*) Reason for having two is that I bought the first one used for cheap, as I didn't know whether it would work. When I had everything perfectly fit, I found a second used one for even less, and immediately grabbed it!
  6. Could you please send a 100% crop at the centre of a SINGLE unprocessed sub? My images improved seriously when passing from the CG5 to the HEQ5, and that was with the ED80 @ 600mm, not the 100! Now it's fine even with the 150pds. What were the guiding stats for that session? --> you're imaging at 1.19arcsec/pixel, need the guiding to stay well below 0.8 RMS, otherwise what you see is bloating due to the guiding/seeing.
  7. Thanks AnakChan, that accessory is the Lacerta one I mentioned in my second post: I know that Lacerta has a kit to use the polarscope even with the camera in place, but it's another 175€, and more weight One more reason (besides portability) for trying to stay with the bare tracker is that I have found a used one in mint condition I could get: only tracker including original polarscope for less than 300€ (whatever it converts to in your currency). Now, as this was exactly my original option I found it very interesting (budget and weight wise), yet if I have to add 175€ for the Lacerta stuff + its weight I really have to reconsider it. Also, I asked about consistency because I could even try it out in the target setup, but I see a risk of having it performing OK the first time but then not being able to get the same performance EVERY time, and at that point it would be hard to manage. While it would produce great photos at the short FLs used by @James, this is something I could already achieve with the Star Adventurer without the L-Bracket and counterweight, which is just half a KG heavier, so not a big deal. Anyway, to be positive, do you confirm that when properly aligned and balanced you can expose for at least a couple of minutes @200mm FL or more? Basically, that the limiting factor for the Polarieat long(-ish) focal lengths is really the alignment and balance, and not Periodic Error or Tracking accuracy. This would be anyway an improvement over the Star Adventurer. Fabio
  8. Thanks for your inputs, from what you mention I'm not extra confident on the performance at 200mm, which is a real pity, as it makes the investment questionable. Actually, I didn't detail too much, but I'm looking for the Polarie as an ultra light solution which appears to me also as quite accurate, as nobody mentioned issues with the tracking accuracy, only with the PA. And I'm looking for that because I am not at all impressed (HUGE understatement) with the Star Adventurer performance. I have used four of them, and unguided none of them was able to track accurately for over 1.5 minutes at 105mm. Furthermore, when used without L-bracket, the Ballhead covers the Polarscope exactly as in the Polarie, but when adding the counterweight, the c-weight bar and the L-Bracket, its portability is much reduced. So, while it's OK for use with the 72ED when guided, I'd rather have something lighter and more accurate to be plane friendly; so @AnakChan, the item you propose adds to the weight and I fancy could worsen the balance thing, because it increases the distance of the ballhead from the axis, like using the SA L-Bracket without counterweight. Do you have a direct experience with it? I plan to use the Star Adventurer's Wedge, which is very sturdy and definitely not the place where flexure could arise. I'm a bit less confident on the aluminium tripod I'll mount it on... or on the Polarie itself, for that matter Absolutely correct, let me address the second topic first: Yes, the Camera + lens system will always be well balanced wrt. the ballhead connection, which does not exclude your first point anyway, because I think there will be difference between the Polarie raising the weight when shooting westwards and breaking it when shooting east, and the ballhead being "bent"/angled. Did you face this issue? So, I'm a bit puzzled at the moment, and somewhat at a loss. On one side it's better to face the possible issues beforehand, rather than finding out after the purchase, but this is leaving me without a solution, because I read that the accuracy on the StarTracker is more "SkyWatcher like", i.e. rather hit and miss, while pretty much everybody agreed on the Polarie tracking precision, despite the possible balance issue. It seems I'm back at start, because it doesn't make much sense to buy the Polarie for use at <100mm FL, and adding weight reduces its appeal wrt, the Star Adventurer. Fabio
  9. I'd say you got it perfectly centred! Now wait for some dark sky ant test it out. Best of luck
  10. In the Polarie User Manual they commit for 1min @ 100mm with 1um pixels: I understand that the tracking should be fine for 2 minutes at 200mm on my Canon 600d (4.3um pixels) at the equator. In fact this would be in line with your statement I found previously, but I don't know under what circumstances it was (and how you managed the PA, what % of keepers...): you wrote that 240" @135mm gave trailing. So 2mins @200mm would be my expectation, IF the PA could be kept after camera positioning, and that's a big IF. I have no doubts that the Star Adventurer wedge would stay put, it is rock solid, and the wooden tripod would probably be OK too. But how would the aluminium tripod fare, and the Polarie itself? What could be a reasonable expectation based on your experience?
  11. While waiting for inputs, I have done my homework and found what some members shared here on SGL, but I still don't have a conclusive idea, in that some positions are very different. I.E. the ones of @AnakChan and @JED-E3 on the polarscope: the former stating "I had problems with my Polarie moving especially when I was switching back 'n forth between the Polar Guide scope & the camera" while for James it was "not too much of a problem". Now, this is exactly one of the issues troubling me: may the difference be in the tripod stability? In the focal length? weight of the camera + lens? I know that Lacerta has a kit to use the polarscope even with the camera in place, but it's another 175€, and more weight. The same issue is highlighted in the fine review by @JB80: Jarrod writes: "[...] having used the Polarie on a number of tripods the small and light one caused me the most grief and was too susceptible to movement and shake": what is the definition of "small and light"? For the accuracy, I saw the great M45 shot posted by @madjohn using a miniborg45 (2 minute subs absolutely untrailed @325 mm FL) , and @Alveprinsen found 2min at 200mm OK but 240" at 135mm trailed and again Jarrod found "easy [to] get 30secs at 300mm" and "at 300mm I can still quite easily manage 1 minute". So basically nobody seems to complain about the tracking accuracy, even at longer FLs, I assume provided a good PA can be achieved. The great images of @James alone are worth the purchase, although they tend to be shot at shorted FLs, which is only one of the planned use cases; and I also suspect experience plays a major role here... Other owners have posted (won't mention all here) and usually the feedback is positive. So, would you advise me to get the Polarie with the setup of the previous post and could I expect to get consistently at least 2 mins at 200 mm? if the work at 300mm mentioned above is confirmed I could even try my SharpStar 72ED @320mm (2kg with DSLR), although it would really be a goal, accepting whatever comes out of it! Fabio
  12. Generally there shouldn't be any need to do so. Only in case you can't centre the scope in any way (which i understood was your case) you need to loosen the one which is fully tightened. On my CG5/EQ5 it's not an issue, because the screws are retaining the full polar scope so, until you make sure the while thing doesn't fall out of the back it's not a problem. I don't know for the EQ6 so heed the advise given by others. Clearly, as long as it's quite centered you should tighten/loosen only in small increments, but i understood that your case was a bit different
  13. Yes, it seems the answer. Quite ugly, though...
  14. Is it 100% crop? I don't find it that bad at all. What are the image specs (exposure, guide, processing)? what was the seeing like that evening? Is your camera monochrome modded?
  15. Wow, that's a minimal design for the mount... Take the front of the Star Adventurer (removing the polarscope), add a slightly modified L bracket and turn it into a manual EQ on a tripod. I don't see a way to couple a motor drive (maybe one the opposite side)? I hope this simplification leads to a real saving.
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