I use the CRT.D3D.br.fx shader in the DAUM version of Dosbox for older CGA / EGA games to make them a little more accurate display-wise. I also recently stopped using the aspect correction function of dosbox and instead vertically stretch the (later era) CRT monitor I have to get the correct aspect ratio; this gives a more accurate image than doubling every 5th row of pixels. However, I noticed that when I do this, the shader doesn't seem to function quite right.

For lack of a better term, very thin "pinstripe" lines that are lighter in color now appear next to where the emulated scanlines are. The affect goes away if I turn aspect correction back on. I'd prefer to leave it off and let the monitor stretch the image for a more accurate picture, but the thin bright lines can be distracting (game-depending).

Is there a setting in the shader I can tweak to take into account that it's to be applied over 200 lines and not 240? I took a look inside, but I have no idea what I'm doing. Any help or direction anyone can off is much appreciated! 😀