user34157: You often/used to hear that "35mm film is 4K, 16mm film is 2K, and Super 8 film is 720p," so why do I often see services such as this one offering to digitize Super 8 film at 4K?
If all of the information on a Super 8 film has already been captured at 720/1080p then what's the point of digitizing the film at higher resolutions such as 4K?
I realize that when a 4K display receives a 1080p input that the display will have to upscale the picture using methods such as interpolation. But if one were to output a Super 8 film at 4K resolution to be displayed on a 4K display, wouldn't you be filling the 4K display with empty pixels given that all of the information on the Super 8 film has already been captured at 720/1080p?

user1950: Calling super-8 720p is confusing. There are no rows of pixels, only grains of emulsion, scattered in a random pattern on the base.
That said, film does have an upper bound on its resolving power, in other words, the smallest detail it can reproduce. Kodachrome could resolve 96-135 lines per millimeter, which can be roughly converted to 180-270 pixels per mm (it takes two pixels to resolve a line). A super-8  frame is 3.3mm high, so the vertical resolution is somewhere between 540 and 810 pixels. So as a back-of the envelope description of its resolving power 720p is a good approximation.
So if you capture super-8 in HD you will be getting enough resolution in your digital file that all of the image that is present on the super-8 frame will be preserved. Higher resolution will just give you more detail of the grain. It won't look worse, but it won't look a whole lot better.
What I would be more concerned about was the fidelity of the colour, and the quality of the transfer. A well transferred, lower resolution transfer will beat a poorly done higher resolution transfer any day. You can just project the film on a wall and film it, but it's probably going to look dreadful.

34157: <p>You often/used to hear that &quot;35mm film is 4K, 16mm film is 2K, and Super 8 film is 720p,&quot; so why do I often see services such as this <a href="https://www.gammaraydigital.com/blog/busting-resolution-myth" rel="nofollow noreferrer">one</a> offering to digitize Super 8 film at 4K?</p>
<p>If all of the information on a Super 8 film has already been captured at 720/1080p then what's the point of digitizing the film at higher resolutions such as 4K?</p>
<p>I realize that when a 4K display receives a 1080p input that the display will have to upscale the picture using methods such as interpolation. But if one were to output a Super 8 film at 4K resolution to be displayed on a 4K display, wouldn't you be filling the 4K display with empty pixels given that all of the information on the Super 8 film has already been captured at 720/1080p?</p>
 1950: <p>Calling super-8 720p is confusing. There are no rows of pixels, only grains of emulsion, scattered in a random pattern on the base.</p>
<p>That said, film does have an upper bound on its resolving power, in other words, the smallest detail it can reproduce. <a href="https://casualphotophile.com/2017/10/04/kodachrome-retrospective-film-profile/" rel="nofollow noreferrer">Kodachrome could resolve 96-135</a> lines per millimeter, which can be roughly converted to 180-270 pixels per mm (it takes two pixels to resolve a line). A super-8  frame is 3.3mm high, so the vertical resolution is somewhere between 540 and 810 pixels. So as a back-of the envelope description of its resolving power 720p is a good approximation.</p>
<p>So if you capture super-8 in HD you will be getting enough resolution in your digital file that all of the image that is present on the super-8 frame will be preserved. Higher resolution will just give you more detail of the grain. It won't look <em>worse</em>, but it won't look a whole lot better.</p>
<p>What I would be more concerned about was the fidelity of the colour, and the quality of the transfer. A well transferred, lower resolution transfer will beat a poorly done higher resolution transfer any day. You can just project the film on a wall and film it, but it's probably going to look dreadful.</p>
