Just a few thoughts on these two displays. I now own both.
TL/DR - The LG Ultrafine 4K is the best general computing display ever made.
The specs
Ultrafine 4K - 23.7", 3840 x 2160 pixels - 186 ppi - contrast ratio 1250:1 (measured by me) - brightness 560 nits (measured by me) - glossy plastic film protecting LCD
iMac M1/M3 - 23.5", 4480 x 2560 pixels - 218 ppi - contrast ratio 1150:1 (measured by me) - brightness 515 nits (measured by me) - laminated glass protecting LCD
My setup
The iMac default 2240 x 1260 HiDPI resolution displays OS-X at its optimal 110 equiv. ppi. I set the Ultrafine to 2304 x 1296 HiDPI resolution to also show OS-X at 110 equiv. ppi. But of course 2304 is 60% of 3840 so there is some fractional scaling involve, rather than the "pure" pixel-doubling of the iMac.
So in terms of desktop space, and how big stuff look, the two monitors are now identical.
My thoughts
The iMac is very slightly sharper, but the Ultrafine has deeper blacks and the screen feels closer to your eyes, perhaps because the plastic film is thinner than the iMac glass. The Ultrafine is also brighter. Overall, the Ultrafine wins by a small margin. Reading text on it feels a little nicer.
A surprising conclusion as I thought the extra 0.5 million pixels in the iMac would win out. Seems the other factors are more important than a pixel-doubled display.
Further notes
The Ultrafine 4K 23.7" also has a better contrast ratio and screen uniformity than the Ultrafine 5K and Apple Studio Display, both of which in reality manage 1000:1 ratio. The Ultrafine 4K 21.5" may have provided an even better image in the past but can't display as much stuff on screen at 110 equiv. ppi - it's too small.
The Ultrafine 4K is now out of production! A shame. IMO the best normal size display ever made.
Would be interested if anyone else has measured their iMac/Ultrafine brightness or contrast ratio?
TL/DR - The LG Ultrafine 4K is the best general computing display ever made.
The specs
Ultrafine 4K - 23.7", 3840 x 2160 pixels - 186 ppi - contrast ratio 1250:1 (measured by me) - brightness 560 nits (measured by me) - glossy plastic film protecting LCD
iMac M1/M3 - 23.5", 4480 x 2560 pixels - 218 ppi - contrast ratio 1150:1 (measured by me) - brightness 515 nits (measured by me) - laminated glass protecting LCD
My setup
The iMac default 2240 x 1260 HiDPI resolution displays OS-X at its optimal 110 equiv. ppi. I set the Ultrafine to 2304 x 1296 HiDPI resolution to also show OS-X at 110 equiv. ppi. But of course 2304 is 60% of 3840 so there is some fractional scaling involve, rather than the "pure" pixel-doubling of the iMac.
So in terms of desktop space, and how big stuff look, the two monitors are now identical.
My thoughts
The iMac is very slightly sharper, but the Ultrafine has deeper blacks and the screen feels closer to your eyes, perhaps because the plastic film is thinner than the iMac glass. The Ultrafine is also brighter. Overall, the Ultrafine wins by a small margin. Reading text on it feels a little nicer.
A surprising conclusion as I thought the extra 0.5 million pixels in the iMac would win out. Seems the other factors are more important than a pixel-doubled display.
Further notes
The Ultrafine 4K 23.7" also has a better contrast ratio and screen uniformity than the Ultrafine 5K and Apple Studio Display, both of which in reality manage 1000:1 ratio. The Ultrafine 4K 21.5" may have provided an even better image in the past but can't display as much stuff on screen at 110 equiv. ppi - it's too small.
The Ultrafine 4K is now out of production! A shame. IMO the best normal size display ever made.
Would be interested if anyone else has measured their iMac/Ultrafine brightness or contrast ratio?
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