I’ve been doing some research lately on image resolution as it relates to all sorts of digital printing, including dye sub. I am trying to make my own web site more helpful to customers, and thought that the information that I found was quite interesting. I created a page on the Wiki with the information that I found. I’m currently building a DPI Requirement Calculator for my web site, and will share it when it is complete. The Wiki page is here: https://dallasmakerspace.org/wiki/Digital_Printing_Resolution
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I can recall similar discussions WRT HDTV, screen size, and viewing distance from several years ago. Perhaps some research in that area would help guide your analysis? The Angular Resolution discussion on this page might get you started:
Completely different dealing with digital vs print. I work for a print shop company as a digital signage engineer, I have this conversation at least 20 times a week 
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The angular resolution issue directly reflects some of what Cary has in the Wiki page he posted.
From the Wiki:
“An image that looks good as an 8" x 10" print from a foot away will look just as good blown up to 16" x 20" when viewed from two feet away. That same image could be blown up to 4’ x 6’ if it was going to be viewed from 6 or more feet away.”
From the Angular Resolution section of the page I mentioned:
“At some point, your eyes are not good enough to distinguish all the details. Studies show that someone with 20/20 vision (or 6/6 in Europe) can distinguish something 1/60 of a degree apart. This means 60 pixels per degree or 32 degrees for a 1080p television. 4k UHD TVs double that to 64 degrees. Keep in mind that you can see a single pixel from further away (depending on its contrast with the rest of the picture).”
Are you talking about resolution?
This guy set the standards a while back
http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/Raylei.html
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