This is the list of scale sizes I use for scaling images to make “PAL VHS” screens in The GIMP:
Broadcast VHS (46.25% worse)
Y 0.299R 215 x 576 100 x 240
0.587G 423 x 576 195 x 240
0.114B 82 x 576 38 x 240
I tend to use non-square pixel 720 x 576 images as source material, or 788 x 576 source material that I scale back to 720 x 576.
Incidentally, the type of scaling you use is important. I nearly gave up on creating VHS style images at first because I was using Cubic interpolation when scaling in The GIMP. It gives very disappointing, blocky results (click to enlarge):
However I soon worked out that, thanks to a bit of help from a clever Hungarian chap called Lanczos Kornél, I could use Sinc (Lanczos 3) interpolation when scaling.
That makes all the difference to the end results. Here is the same image created with Sinc Lanczos scaling:
The sad thing is I probably spent more time on Border Television’s graphics than Border Television ever did when I was writing this post…