[HELP] Capture from 1970s Umatic tape problem

[Selur]

(multiple halos, usually mean multiple sharpening filters applied way too strong, or something is broken)

Is it possible: Yes
Is it a pain: Yes
Will you loose details: Probably, Yes.
What you basically need to do is add multiple dehalo filters and maybe add additional masking to them.
If you want to do this with Avisynth in Hybrid you will need to add a bunch of custom code.

My suggestion would be to get accustomed to LGHost (in Hybrid only available through VapourSynth, but there is a AviSynth port of it).
Base idea is:
1. use LGhost (apply it masked)
2. add additional DeHalo filters (maybe add additional masking)
3. add some denoising
Here's something I quickly clicked together using Vapoursynth: https://pastebin.com/7cwSJU3z
Which is by no means perfect and could be improved, but should show that it's possible:




Cu Selur

Ps.: in bed now, but hopes this helps and gives some ideas.