Retro Computing Roundtable episode 100 began with a discussion of the problems often encountered when trying to connect an 8-bit computer from the 1980s to a modern display such as a typical 16:9 1080p TV or monitor with HDMI input. Open Apple #43 also included some discussion of the out-of-spec video output from the Apple II series, and the resulting problems that can cause with many digital displays.
With that in mind, I decided to try buying an inexpensive composite video to HDMI converter to experiment with. I got it for $19 from Amazon. I’ve heard reports that results vary a lot depending on the particular converter used, the particular version of that converter (i.e., its innards might get a complete re-design without any outward indication… part of the game one plays when buying these super-cheap imported devices), and the particular video source. Thus, my results here may or may not reflect the results you would get.