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TerryMcK last won the day on July 2

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  1. Great. I was thinking Mak Goto too as the reflector they have is not in very good condition and is essentially being used as an ornament in one of their sunrooms. I’ll have a look at that one you’ve linked Brian thanks.
  2. It’s waning at the moment so hopefully it doesn’t cause much bother. We are down in Gloucestershire at the moment in Bortle 4 and last night the moon was low in the sky at 23:30 and due to the optical illusion looked huge. Unfortunately no imaging gear and our friends have decent binocs and an old SW 130 on manual EQ1 or 2 mount. I collimated it yesterday morning with my laser but I think it has taken a knock on the very flimsy eyepiece focuser. I had to bend it back in the tube to get it anywhere near normal. Adjusting the mirror brought it closer back but not perfect. They had had some building work done and it must have been damaged when it was packed away. Anyway they are now looking for a decent goto scope so I am researching something around the £700 to £800 price point. Their interests are constellations, occasional planets (but not too fussed about that) and some bright galaxies but only from a visual point of view. So if anybody has any suggestions then they will be gratefully received.
  3. I’ve decided upon the RedCat as it can have the DeepSky Dad autofocuser kit attached. So it is ordered and I just have to wait for delivery. William Optics won the day again. WO Fanboi.
  4. As I'm using INDI I haven't got it in the FITS header. Apparently it's only implemented in ASCOM. I shall have to dig out a Windows PC with ASCOM on and take a snap or two to see what it is.
  5. Interesting. I left that at default of 1 not really knowing what to put into it. How did you determine the egain value?
  6. This is not a reference to the users of PixInsight, although some may say I'm eccentric, but rather the output of star eccentricity measurements in the SubframeSelector process (not the script as that seems to have disappeared). I have just run a bunch of Ha images through the tool and Eccentricity goes from 0.377 up to 0.791. I thought most of the frames showed quite tight stars when I Blinked them. From what I have been reading an Eccentricity value of 0.42 cannot be perceived by the eye of most people so the closer to that value you get the better. My subframe scale on the ZS103 with x0.8 reducer and ASI183MM is 0.87 arcseconds/pixel In the subframeSelector Expressions table I entered FWHM < 6 && Eccentricity <= 0.6 (as Amy Astro suggests) with a weighting of SNRWeight The results for 93 subframes is 51 ok for approval. It was a lot less for OIII and SII making me wonder if doing image analysis is actually detrimental. Approved frames start like this: Unapproved frames end like this: Raising eccentricity in the approval formula to 0.7 results in far more usable subs but of course more eccentric stars. I then compared the stacked images in SHO after doing some very basic processing first with all subs stacked and then with only subs that SFS approved. Zoomed in images showing all subs on the left and SFS approved subs on the right integrated as SHO - not a pretty picture but was not meant to be The only difference I could see in the Hubble pallet was less red ringing around stars with the frames output by the SFS process. This is after magenta halo removal. Although the SNR of the all subs stacked integration was far better than the one which only had 50% of frames integrated. I then changed the approval to the generally accepted formula through SFS which is 20*(1-(FWHM-FWHMMinimum)/(FWHMMaximum-FWHMMinimum))+20*(1-(Eccentricity-EccentricityMinimum)/(EccentricityMaximum-EccentricityMinimum))+10*(SNRWeight-SNRWeightMinimum)/(SNRWeightMaximum-SNRWeightMinimum)+50 and guess what? Every frame passed muster. Surely that cannot be right as the FWHM and Eccentricity values were still the same as before. There might be issues with that formula. I wonder if the residual red rings remaining after magenta deringing are caused by the Sulphur filter bloating the stars so might invest in 3nm filters soon. Mine are all 6nm currently. I may be being a little picky on this but SHO red ringing around stars irritates me. What Eccentricity values are you seeing?
  7. Very nice. The RedCat has got the dusty stuff around the nebula too.
  8. A massive rainstorm with thunder! To be fair it was forecast as possible I only got notification by one of the cats running in and announcing at the top of her voice - I’M WET, in cat speak of course, not that I am fluent but as she was soaking wet it was a good guess. Fortunately the scope is under its covers and is fine. A look at Ventusky reveals it is going to be bad throughout the night. Meteoblue agrees as does ScopeNights. However the app Clear Outside says it is going to be wonderful. I might just throw that app away!
  9. I captured 50 subs of OIII last night. There were a few with egg shaped stars mainly after the meridian flip so I scrapped the subs containing those. So now have 42 for a total of 90. I think seeing was a little poor last night judging by my guide log.
  10. We’ve all done that Brian 🙂 I have taken my first sub of the night OIII on the wall. Hope to add another 5 hours or so to the OIII I already have. You can’t have enough data! Probably will have 30 hours of Ha, OIII and SII on the target if I get another night tomorrow where I aim to shoot 5 more hours of SII.
  11. Just to step in on your guiding issue @gabs have you tried the ST4 cable direct from the camera to the mount and configure PHD2 to use On Mount instead of EQDIR? I know in the early days that's what I did and had good results.
  12. sun stopped play after 51 subs were captured. I’ve not had a look at the last ones but imagine at least one will be scrap.
  13. No issues with EKOS. Just on sub 48 of 55. No sign of the sun yet but maybe in a short while it will stop play.
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