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Sony Unveils Smartphone With 4K Screen
An anonymous reader writes: Sony has taken the wraps off its new Xperia Z5 Premium smartphone, which has a 5.5" display that operates at 4k resolution. "The company acknowledged that there was still a limited amount of professional content available in 4K — which provides about four times the number of pixels as 1080p high definition video. But it said the Z5 Premium would upscale videos streamed from YouTube and Netflix to take advantage of the display." Sony's answer to the obvious battery concerns raised by such a pixel-dense (808 ppi) screen was to use a 3,430 mAh battery and memory-on-display technology. The video upscaling can also be turned off to decrease battery drain.
...high-definition bionic eye implants to be able to see the difference?
The eye has higher effective resolution than Apple has led us to believe with their "retina" marketing. This article shows how human eye can see 530 ppi resolution in a 20 x 13.3-inch print viewed at 20 inches. http://clarkvision.com/imagedetail/eye-resolution.html
high definition root kit?
by TheSpoom (715771) Uncaring Linux user here. I have nothing to add to this but please continue. *munches popcorn*
The maximum physically possible resolution for the human eye to see is 2190 dpi. But that's not an average eye, but rather a flawless eye limited only by the size of the pupil; and viewed from as close as an adult can focus, 4 inches.
If we downgrade from a perfect eye to an average eye, the resolution drops down to 876 dpi... but still at 4 inches.
At a more practical 12 inches, this drops to around 300 dpi. Which is why magazines are printed at 300 dpi - it's good enough for most practical circumstances.
Also note some additional limitations:
* These sort of resolution figures are based on the ability to distingish bright white lines from bright black lines without them blurring together into gray. The smaller the contrast and the dimmer the light, the less the eye can resolve.
* The human eye also loses a great deal of ability to make out resolution when objects are moving.
* Obviously the further away one is from the center of the field of view, the lower the resolution - with a rather fast dropoff.
Yes, 808 dpi is complete and total overkill, unless you've got superb eyes and are in the habit of holding your phone as close to them as you can focus while looking at high contrast stationary images.
Stale pastry is hollow succor to one who is bereft of ostrich.
20/20 vision is defined by the ability to resolve 1 arc minute. For example, the "E" on an eye doctor's chart on the 20/20 vision line is 5 arc minutes tall, as reading it takes the ability to break it down into five vertical glyphs and distingish between them. That page is based on the premise of a person being able to resolve 0,3 arc minutes.
Problem.
Also, see above. The human eye has a lot more limitations than just a simple single angular resolution figure can express. I even forgot to list one: time. Not only does motion greatly limit one's resolution ability, but even on a stationary image, the person has to be able to focus and take time in order to get even "normal" levels of visual acuity.
Stale pastry is hollow succor to one who is bereft of ostrich.
I did some side-by-side comparisons between a year-old Samsung 1080p set, and a new Samsung 4K set.
NetFlix 4K looks a lot better than their 1080p service, but just like the 1080p service, the video is over-compressed, so fine detail is missing. YouTube 4K videos look amazing.
Not that it has stopped some, but a 16:9 display in a phone is not optimal for VR. It is difficult to drive such a display while doing something interesting, and a phone just doesn't have the CPU to do it locally, or the bandwidth to do it remotely.
An wired 8:3 would display would be a much better fit, as it matches the human visual field more closely, and wouldn't require batteries or other useless hardware.
You do understand that 1080i has precisely the same spatial resolution as 1080p, right? There is no field fade (whatsoever) on an LCD, as there is on CRT. And the temporal resolution depends on the respective frame rates. 1080i is 60 fps in the US and other NTSC-legacy areas, and 50 in Europe and other PAL-legacy areas.
1080p may be either 24, 30, or 60 fps in the US, and 25 or 50 in Europe. The lower figures are the norm for film-derived material, since film has 24 fps. The lower figures give you in fact a LOWER temporal resolution for 1080p than for 1080i. The higher figures give you the SAME temporal resolution for 1080p as for 1080i. The difference is that in 1080i, only 1/2 the 2,073,600 pixels change every 1/fps seconds, and in 1080p all of the 2,073,600 pixels change every 1/fps seconds.[*]
In scenes with no motion, there is no difference in image quality whatsoever. None. 1080p and 1080i give identical images. Only in scenes with significantly rapid motion does 1080i introduce noticeable artifacts that aren't there with 1080p.
[*] The actual situation is modified by various motion-smoothing video-processing algorithms employed in any good-quality interlaced display.