Beats me, but that's not really my point anyway. Displaying photographs was cited as a good use case for an e-ink display, and as a photographer who puts considerable effort into producing high-quality display prints of their work, I felt it worth explaining why that's a terrible use case for e-ink.
(Anyway, why do people frame newspaper front pages? Given the total lack of archival quality in newsprint, I could see scanning and printing to frame in a way that'd hold up better over time.)
The advantage of e-ink is that it blends perfectly with the ambient lighting, without eyestrain or backlight bleed. Low contrast is kind of the point, combined with the ability to change the display remotely/automatically.
What's here under discussion is contrast ratio - not contrast between the image and its surroundings, but contrast between the lightest and darkest tones that can be represented within the image itself. Another term would be "dynamic range", if that helps; "contrast ratio" is how the concept is typically expressed in the context of raster displays, so that's what I've gone with here.
Under either name, it's a major figure of merit for quality of image reproduction, and my point is that e-ink, being worst at it of any raster display technology of which I'm aware, is thus a very poor choice for displaying images if quality of reproduction is a criterion.
I know, and quality of photographic reproduction is not a criterion I would need from an eink display. My goal is subtlety. Honestly in a parallel universe I have probably built the same exact prototypes from the blog. My (defunct) startup was called Nitrogen Logic because technology should be as critical but invisible as the nitrogen in the air.
I am totally fine with an 8:1 contrast ratio if it gives me perfect integration into the ambient light :)
Photography would be displayed elsewhere, in a place that is meant to draw attention. I want eink because it shouldn't grab attention at all.
Family vacation? The LCD picture frames are popular and can be described just like that. Even the kindle grayscale images could be decent as decoration. (I'm guessing e-ink would look best in grayscale, but I haven't seen one in color)
Even there, much better options exist. For the same money you can get a 55" Samsung Frame with color, excellent contrast, and that also doubles as a quite good TV - it can be the living-room centerpiece.
Much better for what? I'd never use that - absolutely hideous for the use-cases I'd use an e-ink for.
I'd use the one in the article in a heartbeat, much more elegant and no backlight. No it won't display a photograph as good as the Samsung but it will not be cheesy or look out of place (or consume tons of energy) - which the Samsung will if it is positioned anywhere else but in front of and in eye-level of a sofa.
The only thing it is good for is as a TV, which I guess is great if you want a TV.
I'd rather take a chance on the Frame's automatic backlight adjustment to match the ambient light level maybe working, than on e-ink which guarantees poor reproduction.
It's just super odd to me
to think about wanting to
go to all the trouble of displaying an image at that size and scale, and also being willing to accept it looking as lousy as e-ink's awful contrast will necessarily make it. Sure, it's a lot easier to change the displayed image than it is with a paper print, but what's the benefit of that when they're all going to look equally bad?
Granted I'm a photographer and I want my own work to look good, but it's not as if I had to develop that interest to want whatever I did put on my walls to look good...
(Anyway, why do people frame newspaper front pages? Given the total lack of archival quality in newsprint, I could see scanning and printing to frame in a way that'd hold up better over time.)