Which one? There a dozens commonly used ones
Dosbox Staging has one CRT filter which is the one I’ve used. The town wall graphics get competely messed up with it. It is possible the bad effects for each of the 4 games mentioned was caused by a bad CRT filter.
That said it would’ve been better to include screenshots which do use the CRT filter. I have played all 4 of these games with and with Dosbox Staging’s CRT filter and they all have had black lines obscuring the screen. Not having it enabled, on the other hand, the games looked like these screenahots.
No CRT filter screenshots that I have available. I do not have screenshots for the CRT filter. I suppose I could boot up and try to put the filter for this one; I have Heroes 2 installed too but it is currently a pre-configuration I do not want to mess with in case I possibly mess it up. It feels like a pain to do so though as I’m already occupied for the day, and would like my PC time to, you know, play. Since this is unrelated to help requests, in which case I may have made time for it (I’d usually do it in the past, but not for a while).