Starwiz

Yes, I definitely lost the star sometime during the night probably due to clouds coming over. I still got 14 x 360s of OIII, so the session was worth it. John

Many thanks for the advice Ken, I'll try it out tonight if it stays clear. John

Thanks. I think this the relevant log. Star mass changed? PHD2_GuideLog_2020-07-15_232352.txt

I started guiding last night and did a calibration first. It seemed like every other frame, the PHD2 window flashed red like it had lost the guide star, but the guiding looked fine. The guide star was also bright enough. I'm using OAG. The only time I've seen this before is when the guide star disappears due to clouds. Any thoughts? John

Yes, quite possibly. I have two laptops and it looks different on each due to the screens. It looks different again on my mobile phone, where the colour saturation always looks much higher. John

Imaged from Mellieha, Malta during the last week. I wasn't happy with the way the standard Hubble Palette turned out, so I swapped the mappings to: SII = Red Ha = Blue OIII = Green John

Welcome. You'll never forget the first time you see Saturn. Enjoy. John

John, I use CdC, but have never tried Stellarium. Does either have advantages over the other? Thanks John (A.K.A. Starwiz)

Not quite sure what's going on here, but the unwanted artifacts at the bottom of the image don't show when I open it on my machine?

NGC 6960, 'The Witch's Broom'. Imaged over several nights from Mellieha, Malta in SHO. The stars were shot in RGB and were processed separately. This was a difficult one to process because of the very bright 'witch' star. 61 x 360s Ha 41 x 360s OIII 56 x 360s SII

That's what you think. 😆 This is how it all starts, and before you know it....................

Thanks. Hopefully I'll be getting a coma corrector in late December. I've written to Santa already. 😀 I last collimated a couple of weeks ago, but will re-check. Green hue on star - I've used a lot of clone stamping on the mono images to removed the star, so will take another look. Thanks for your help. John

So here's my attempt at controlling the 'witch' star. I've still more work to do on correcting some of the coma and cropping out a few stacking artifacts. I also want to alter the hue of the bright star as it's looking a little green. Comments for improvements welcome as always. John

Thanks. I'm using Straton to remove the stars, but the brightness from the 'witch' star is such that much of the area surrounding it becomes brighter than the nebula when stretching. John

That's interesting, thanks. I'm processing in PS, so there may be an equivalent way to do the same. John

I'm processing in PS. I've had a good search in the NGC6960 posts, but haven't been able to find anything useful. John

I guess that's a 'No' then. 🙂

This was my primary a couple of weeks ago just before I cleaned it for the first time in about 10 years. The secondary was just as dusty, but I'd been taking great images without any noticeable effects. John

I think it works that APT sends a command to PHD2 to tell it to dither, so I think this would be a problem if both were running on different laptops. APT needs to do this as PHD2 doesn't know when the imaging frame has been completed. John

I just thought. If you're using one laptop to control guiding and another for imaging, how would dithering work? John

Thanks, I'll have a look. John

That's under your control. Move to mid Wales. 🤣 Cheers John

Thanks. I have two laptops although one is quite old, but I'll give it a go. Yes, I was seeing PHD2 losing the guiding camera, then reconnecting last night so it sounds like it could be the same problem you've seen. John

If you could change one thing to remove some of the frustrations of deep sky imaging, what would it be and why would you choose to improve USB connections reliability? I began setting up my imaging run last night which took two hours because of connections reliability. I finally got the imaging run going with 360s SII frames and waited to check the first frame came out OK. The imaging camera, my ASI1600mm-Pro wouldn't download the first image. I checked everything and in PHD2 I noticed that the guide star looked a lot smaller than when I set it running. What had happened was, my guide camera had disconnected and PHD2 had grabbed the main imaging camera and started guiding from this. Very weird. After fixing the connection and updating the camera in PHD2, I had to shut down APT and reconnect. It ran fine until about 3 in the morning when I think a similar problem must have occurred as it was still trying to download an image when I went back out at 5 AM. John

Does anyone know of any tutorials that deal with processing images that have a really bright star? I've been searching the web but can't seem to find anything. I'm processing some NB data for the witches broom NGC 6960, but the bright star is over-saturating. Thanks John