Any tips on brightening background star fields?

[JoelHruska]

I'm hoping someone here might have some advice on the best way to brighten background star fields when working on TNG-era Star Trek. The filters I use in AviSynth tend to be somewhat destructive to starfield detail -- they wind up dimmer as a result of some filters and can vanish altogether depending on processing method.

I would like to do this as part of a single filter chain that I can tweak on a per-episode basis to target the relevant sections of the footage, but I'm willing to encode the two same video with two different workflows and then merge the outputs if that's what is required. I don't know if there's a way to preferentially brighten the background of an image without touching the foreground and I don't have any experience with masking in AviSynth.

I've experimented with some ideas and have not found a solution that I liked very much.

Samples for experimentation, if anyone is willing. This is original footage off the DVD, without any prior processing. I've included the credits and a clip from the actual episode.

https://1drv.ms/v/s!AphTLFRW13WMkE1bnCJC-N2g4EW8?e=2oL7yo

https://1drv.ms/u/s!AphTLFRW13WMkE45SbejWEjK3Y2t?e=hNgTwt

[jagabo]

So you're looking to brighten the individual stars so they don't disappear with your other filtering?

[JoelHruska]

Yes. So far, the best method I've come up with is to create a specific version of the video that has very bright stars and then to blend it with a clip that I've put through usual filters. This can work -- heavily noising the "bright stars" video allows Topaz Video Enhance AI to pick up the stars better, and it brightens them nicely -- but then I'm blending somewhat damaged foreground output into a second video stream just to get a better background.

I'm willing to create and blend more than one version of the same clip but I am hoping to find a method that doesn't blend in damaged output the same way.

[jagabo]

Stars (small dots) can be greatly accentuated with a simple sharpen. You'll probably want to use an edge mask so that other edges don't get sharpened.

[Selur]

CAS