What codec do I use for QuickTime 10.4 when rendering non-animated video?

What were your render settings? I hope you used Constant bitrate - so what was the bitrate? Increasing it should help but one should be cognizant that at sufficiently high levels, only marginal improvements will be perceptible; by a fair few.

caal66  wrote I recently digitized some old low-resolution family VHS tapes, edited them in Premiere Pro CC 2018 using a MacBook Pro late 2013 version, and rendered them in Premiere Pro using the H.264 codec with QuickTime 10.4. The rendered videos do not have the same sharpness as the project previews.

(I also have an ElGato Video Capture that I use with Premiere Pro on the Mac) Do the Premiere Pro exports look the same at the same size? Because VHS can look sort of OK when you're editing in the little Program panel, but when the final exported video is viewed full screen, especially on a current TV many times the size of the TVs originally used to view VHS, VHS can look very disappointing.

For example, I would expect that if you played back the previews from the Premiere Pro timeline in full screen (press Ctrl+` ), they should look comparable to the exported video played back full screen.

If that's not the problem, and bitrate is not the problem, you could try this in Premiere: Open the Lumetri Color panel, open the Creative group of options, and increase the Sharpen slider. That might only work up to a certain point, since VHS probably won't withstand much sharpening, but it's something to try.

Well, QTX pretty much stinks anyway.  QT 7 is lots better.

And you don't need to be in AE -- stick with PP.  AE's NOT going to do a better job with H.264.