iPads have high resolution screens.

Cheap USB capture devices usually support a maximum of 1080p@60Hz output. If you buy a random '4k' USB capture device, it probably supports up to 4k input but then scales it down to 1080p for output.

So perhaps 4k upscaling on the ipad will make the image look better.

There's also the issue of chroma subsampling, giving you YUV 4:2:0 or 4:2:2 instead of YUV or RGB 4:4:4

This page https://obsproject.com/forum/resources/capture-card-document... warned me about it, but I haven't seen any updated info on the newer AVermedia or Magewell interfaces, for instance https://www.magewell.com/products/usb-capture-hdmi-4k-pro This gives 4k60 4:4:4 only on the loop-thru output, higher resolutions require 20GBps USB 3.? but my Mac only goes to 10. I'd need Thunderbolt capture which start around $1000 https://www.bhphotovideo.com/c/product/1500555-REG/blackmagi...

I'm using an Elgato CamLink 4k at 1080p60 for now & I'm wondering if the awful mouse feel in Linux (with a Mac for display) is maybe due to delay. Going to get a cheap-ash monitor to simplify. I thought it would be nice to have my 6k Pro XDR display have windows from all computers, but it's just too messy.

I presume this software has two users → those wanting to read text on a server, and those wanting to use their iPad as a screen to watch movies from a DVD or similar player.

The second may like upscaling.