Luminous stars problem: they are big

I'm interested the responses on this one but to me it looks more like a filter, lens or OTA issue. The second image does look way over-processed. Best to reset APP to factory defaults when something like this goes awry.

Luca

It looks to me that the image has been overstretched to the point where the faintest parts of the diffracted light around the brighter stars have been made visible by APP.

Don't take that as a criticism - its something I often do myself. The solution I often use is to save two stretches, a weaker stretch for the stars and a stronger (probably overstretched) version for the nebulosity. I take the stars out of one and the nebulosity out of the other and combine them in Gimp.

I use Starnet++ for this. I'm sure the star removal tool in APP can do it too, but to be honest I've had trouble getting the hang of it.

JC

Yes, I perhaps pulled the image a little, I wanted to see the differences on some of my old photos taken with the SLR many years ago .. to separate the stars I use the Starxterminator, but I see that the stars problem is already in the linear phase..Allego the photo that came out of the app without making any modification.

That "luminous star" above the nebula is actually three bright stars that should be separated in your image. So either the instrument is severely compromised or the image is over processed - don't use any exterminators or reduction tools - just integrate and auto-stretch to see what you get. I have an ES ED102CF, similar to the Tak and the three stars are separated.

I've gotten confused. I don't know if you are posting DSLR or Tak images, or if you are illustrating changes in the software or the camera or both. I suggest you reset APP to factory settings and start your analysis from an unmodified sub from the Tak - forget about the DSLR, its just confusing the issue. I assume the Tak is excellent but better to inspect it. And anything you may have changed on the Tak after the focuser - like an extension tube or reducer - may be introducing stray light.

Also, you might try doing a complete integration without any calibration frames - a good way of troubleshooting some processing issues but probably not going to help in this case.

Good luck

@astrogee 

To make the problem understand I initially posted two crop of photographs; I chose an old photo taken many years ago because I could have a comparison with an old software and the new;
The first photo is made with the Iris software,
No longer updated for 15 years and you can see that triple star and from the image it is seen (perhaps the compression has crouched a little), the second image instead developed with AstropixelProcessor, and that triple star disappears making a unique large star,
The third photo is always from Astropixel but the linear without any kind of processing and you can see the triple star which is always as if it were unique; So it should be something linked to the software and not to the instrument.

I also looked at the roughs not elaborated with my new room a QHY168C,
And the stars are the bright and intrusive ones are not so large, a portfilt has been added to the optical train, which was not there before, I was not there, I use a UV/IR Cut Astronomik filter, I think of a good workmanship.

Thanks for the intervention

I attach other comparison; Fit files from QHY without changes, and finished elaborate file (they are cut out)