I post too Much on Here!!
- Jul 21, 2010
Apple’s retina displays use logical pixels comprising four real pixels. A 1:1 photo viewed on a Retina display is one image pixel rendered as one logical pixel. It’s still 1:1.If the resolution is too high, you might not be able to see a single pixel. Apple calls that "Retina Display" and they say that the resolution is so high that you can't see the single pixels. That is what I want to avoid. Of course you can always watch an images at 200%, but some programs will just interpolate 75% of all the pixels then. It only works if 200% means that every pixel is shown four times like Photoshop for example does it. An 8K display has even tinier pixels than a 4K display. Of course you can see more of the photo at 1:1 then, but you will not notice a single "wrong" pixel because it is just too small.
Try this: check your screen resolution in System Preferences (default on my 16” MBPs is 1792x1120), then open any large image Photoshop and crop it to the screen resolution dimensions, open the resulting image in Preview, hit command-zero for 1:1 and go full screen; your 1:1 image now fills the screen. Take a screenshot and you’ll get a resulting png file doubled in horizontal and vertical resolution, e.g. that 1792x1120 image yields a 3584x2240 screenshot). At 1:1, Apple is just spreading one image pixel over 4 screen pixels in the GPU that are rendered back down to one pixel. All that is behind the scenes in the GPU. Note that Apppe does that on external displays up to 4K as well, so when you connect your HD monitor to a Retina Mac, everything you see on your display was rendered at 4K in the GPU then downsampled. With display resolutions >4K (at least on my 16”), that doesn’t happen – when the resolution on my 5K:2K ultrawide is set to 4K wide, I get a screenshot that’s 8K wide; when I set the resolution to 5K wide, I get a 5K wide screenshot because the GPU cannot render at 10K.
The bottom line is 1:1 is always 1:1, and your reasons for preferring lower resolution monitors are totally specious (as are your reasons for preferring lower resolution sensors).