Comment by LocalH
7 months ago
DAR is perfectly fine to use, as long as the entire image (including any borders) is included in the calculations. Thus, all images from the same system should end up with the same scaling factor.
7 months ago
DAR is perfectly fine to use, as long as the entire image (including any borders) is included in the calculations. Thus, all images from the same system should end up with the same scaling factor.
You can, but it's not a useful basis for comparison. The full pixel display area including borders for an Atari 8-bit system is 352x240. The 22:15 ratio that comes out of this is not generally useful, because most displays do not show this full area, nor can it be compared to broadcast specifications to determine how it will be nominally displayed. It certainly is not comparable to the 4:3 ratio that is frequently used to try to fit retro system displays.
The pixel aspect ratio is not affected by how large the active display region is. Displays can't even detect the border if the border is at blanking level black as older systems tend to do. It's determined by the horizontal/vertical timings and the pixel clock. Those can be compared to the specifications for NTSC/PAL square pixels to calculate the resulting display size and aspect ratio on a standard-tuned display for a given image pixel size.
Right. You're not going to use V-size and H-size to remove the borders because that screws with literally every other use of the TV (other computers, TV shows, etc)..
About the only way to properly calibrate what the borders "should" be is to calibrate the TV to what would be a reasonable approximation for SD TV signals, and POSSIBLY make small adjustments after that point if the computer looks wrong.
Even then, every TV is going to be somewhat different and so there's a huge amount of variance on how it's going to look in the end. Same applies for computer monitors back then, though calibration of an RGB monitor is going to be even harder than composite since you can't easily run a VCR over it to try to get SD TV calibration.