MiSTer FPGA Forum

Hello,
I found a seller near my place that sell a A serie 20' BVM crt (A20F1E to be exact) at great price, i am not interested by buying it but i am curious of something so i will probably ask the seller a small experiment. If you are interested by crt you should probably know this series is plague by the very rare and expensive analog card. The previous D series that feature the rgb by default is rare and expensive, when the A series is easy to find, and some seller make great discount because in fact no one want them...
This BVM have a sdi and hd-sdi input, sdi support 480i and hd-sdi 720p or 1080i. I am not very interested by the interlace res only the 720p, but i was thinking of something. Most people find sdi useless because if you want to use it with old console you will have an inelegant video chain that is suppose to add latency : console digital video => console DAC => ADC => SDI => BVM DAC => analog. It's the same problem with external scaller, one useless digital to analog and analog to digital conversion.
With mister on the other hand a simple hdmi to sdi keep the signal digital and i don't think it add much latency. I was asking myself how the A20 could look with HD-SDI 720p and the good mister filters vs a similar bvm in 240p ? What filter can you recommend to look as close as possible of 240p (with scanline) but in 720p ?

Thanks !

I think the scan lines will end up looking pretty funny. You'll have a mix of very small scanlines from the actual CRT (3 small scanlines per pixel line) and then one large scanline per pixel line from the scanline filter. Running native 240p will just look right without jumping through hurdles.

I never saw an image in 720p on crt. Even in 480p the scanline appear a lot smaller, so in 720p are they really visible imo ?