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FaDG

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About FaDG

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    Star Forming

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    Rome, Italy
  1. Hi Peter, thanks for sharing the result! may I ask you why you prefer the D2 image? In this narrow vs. Moderately wideband comparison, the signal seems comparable, but the Sky background is darker in the Optolong one, so you're not taking advantage of the NB ability ti increase the exposure time. A comparison with similar background levels would also be interesting.
  2. Skywatcher 72ED + flattener/reducer + dew strip should be around your target point
  3. A few mixed answer to specific points in previous posts: Yes, definitely. Life is too short to lose frames due to trailing. I wouldn't run my 72ED @ 320mm unguided, let alone the 150/750! And by no means a 200! Feel free to try, but be informed that I bought my HEQ5 second hand from a guy that wasn't satisfied of its performance with a 200p. For me it's just magical with my 150. Additionally to the collimator mentioned above, you'll find a coma corrector quite a must. Warning if going the OAG route. Most newtons don't have enough backfocus for that. My 150p not for sure, more so with the comacorr. And, depending on where you live, filters might be in order. I image from the centre of Rome, so narrowband is the only way
  4. IMO, the 200 is a bit the limit for the HEQ5. I use a 150p on mine and it's a great setup. But I concur that a reflector is slighly more complex to master than a refractor. Yet, I also have a Skywatcher ED80 I used as a first imaging scope, and there is really no comparison between the two! The frac doesn't get much use, nowadays. All the best, Fabio
  5. Yes, that's better, IMO. You could keep one of you previous lights as reference so that next time you can point the camera with the same orientation and add more integration time. Then, if you use your UHC to cut through light pollution, the new image with more contrast could become your luminance layer, and the previous one (with unfiltered colour) be superimposed as RGB after coregistration. In this way you could benefit from higher contrast and SNR, AND keep natural looking colours.
  6. Nice shot, Vintage lenses offer a great value! You could add more lights on different nights and a modded camera will give you a lot more signal. Here is the same target acquired with a different vintage lens, but same focal length : Jupiter 135 f3.5 (the radioactive one, I fancy it could produce an image even when left in a closet! ) on a modded Canon 600d. For this shot I have added a 2" IDAS V4 in front of the lens, to keep light pollution at bay.
  7. A lot of data in there for the short integrato time! What is the used setup and where did you shoot from?
  8. 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
  9. 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?
  10. 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.
  11. 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!
  12. 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.
  13. 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
  14. 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
  15. I'd say you got it perfectly centred! Now wait for some dark sky ant test it out. Best of luck
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