Advancements in processing software include the ability to remove the stars from an image and recombine the stars from the same or a different exposure. In order to preserve the color of the star field it is important not to saturate too many stars and too many pixels in any one star. I understand we have an exposure calculator, but that is mainly concerned with swamping the read noise and gathering enough exposures to reach a desired level of S/N.

It would be beneficial if the Fits Viewer could present the number of saturated pixels in an image, so we could determine what minimum exposure to use in gathering just the star data to preserve the most color in the stars.

I don't think the current 'statistics' include this number (I would be happy to be told different).

thanks,

I think this is already implemented:

Thank you, is that in 3.6.8 or 3.6.9. I am currently running 3.6.8 and I don't recall seeing it, but I may have missed it.

I'm running 3.6.9, but that feature was implemented way earlier, at least last year.

The feature to color clipped pixels red in the FITS Viewer and display the number of clipped pixels on its status line was released in version 3.6.3 (released at the end of January 2023). It is mentioned in a few places in the KStars Handbook: docs.kde.org/trunk5/en/kstars/kstars/kstars.pdf. See the FITS Viewer chapter (docs.kde.org/trunk5/en/kstars/kstars/kstars.pdf#fitsviewer).

Note that you need to enable this by either going to the View menu and selecting "Show Clipping" (or the corresponding control-L shortcut--that's lower-case L) or by clicking on the red circle icon above the image display in the FITS Viewer. All of these toggle the feature on and off.

Also, the definition of "a clipped pixel" is defaulted to a value that may/may-not agree with your own definition. It starts out as 60000 for 16-bit values (note that 12 or 14-bit cameras are converted to 16 bit internally). However, you can modify that definition by going into the main KStars Settings menu ("Configure KStars"), then selecting the FITS tab, and then changing the "Clipping Limits" values.

Hy

Thank you for this information, I was unaware of that capability. I will spend some time going thru the Kstars Handbook on this and other features. I have been using Kstars for several years now, but I admit that I have only updated the version I am using as new features were presented that I felt warranted the upgrade. I have not kept up with ALL of the changes and additions.

I encourage you to not only read the manual, but improve it if you see parts that are not up-to-date or could use reworking. This is an open-source user-contributed project and we could use the help.

The doc source is here: invent.kde.org/education/kstars/-/tree/m...r/doc?ref_type=heads. It is in docbook format (I never heard of it before I started contributing either). The README page invent.kde.org/education/kstars#making-updates-to-the-handbook describes how to make updates to the handbook, but if you are not up to submitting a doc merge request, I or others could do that if you submitted text and pictures in some way.

Hy

One suggestion would be to list what version the manual refers to and what is the date of the latest update. I don't recall seeing that when I looked at it.

I will consider what I may have to contribute to the manual.