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A Canvas Made of Pixels

claybavor.com

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Re: A Canvas Made of Pixels

#101

Post by mark-r »

benbenolson wrote: post #36

He says in the article that "Apple did a good job with their monitor", but what he fails to realize is that the panel in that monitor is made by Samsung, and is used in numerous other monitors, such as a bunch of Dell Ultrasharp monitors. These are the exact same monitor, except with a different frame and stand, and are available for a fraction of the cost.

His analysis assumes you're going to get up close to the picture to really examine the detail, up one foot away. The resolution requirements are based on that assumption. I think that's unrealistic, and a much cheaper monitor would be just as effective in creating the illusion.

Re: A Canvas Made of Pixels

#103

Post by morsch »

mark-r wrote: post #100
KingMob wrote: post #93

Earlier quoted context omitted.

Kudos to Apple for making the new iMacs wide-gamut. But I don't know that it's too common in the consumer space yet, mostly because once you start using multiple color spaces, you run into the problem of images created in one color space being shown in another. If the image data isn't tagged correctly, things will look over/under-saturated on different monitors. (E.g., is rgb(255, 0, 0) the reddest red in sRGB or the…

Unfortunately as the gamut gets larger, so does the visual difference between adjacent colors. You need more than 8 bits per channel from end to end if you're going to use anything wider than sRGB. Any RGB based color space will be triangular shaped; if it's to be physically realized in a display, all 3 vertices must lie within the CIE gamut. Since the CIE gamut isn't perfectly triangular you will always be missing s…

Is the CIE gamut "it"? In other words, are all colors perceivable by a typical human represented by it? I briefly scanned the Wikipedia article but wasn't any wiser.

Re: A Canvas Made of Pixels

#104

Post by mark-r »

morsch wrote: post #103
mark-r wrote: post #100

Earlier quoted context omitted.

Unfortunately as the gamut gets larger, so does the visual difference between adjacent colors. You need more than 8 bits per channel from end to end if you're going to use anything wider than sRGB. Any RGB based color space will be triangular shaped; if it's to be physically realized in a display, all 3 vertices must lie within the CIE gamut. Since the CIE gamut isn't perfectly triangular you will always be missing s…

Is the CIE gamut "it"? In other words, are all colors perceivable by a typical human represented by it? I briefly scanned the Wikipedia article but wasn't any wiser.

Yes, the CIE 1931 color space is generally accepted as the limit of human perception. I don't know how much variability there is from person to person, since it's based on averages. There are a small number of Tetrachromats that can distinguish a greater variety of colors, but I believe those colors are all still within the gamut.

Re: A Canvas Made of Pixels

#105

Post by claybavor »

benbenolson wrote: post #36

He says in the article that "Apple did a good job with their monitor", but what he fails to realize is that the panel in that monitor is made by Samsung, and is used in numerous other monitors, such as a bunch of Dell Ultrasharp monitors. These are the exact same monitor, except with a different frame and stand, and are available for a fraction of the cost.

(Hi there, I'm Clay, the creator of the picture frame mentioned here.)

You're correct that the same panel is in the Dell display, but I'm pretty sure it's made by LG, not Samsung.

I purchased one of the Dell displays for testing purposes, and unfortunately, for reasons I don't fully understand, the color on the Dell display is quite a bit worse, with non-uniform color over the display from left to right, and also variable gamma at different brightness levels. The iMac also supports finer-grained control of brightness, which you need for luminance matching. All of this makes the iMac and its display a better choice for this application.

Re: A Canvas Made of Pixels

#106

Post by claybavor »

ohitsdom wrote: post #24
chrismbarr wrote: post #12

I'm really surprised there's no photos of the build process. It's hard to tell if this is actually what is being described, or just a blog post around a photo of a framed image.

Build photos would have been really cool. Also, some detail on the software would be nice. I'm assuming it's running on OSX, but I still have lots of questions (what language, how can you change the picture, how does he manage it remotely, etc).

First of all, yes the frame really exists. :)

If I get around to pulling together build photos (which by the way aren't that exciting), I'll post them here. For now, just imagine a big hole in my wall (I had to reframe it), a photodiode sticking out of a hole on the right side of the picture frame, and an iMac.

The software is just a simple Objective-C / Cocoa app running on Mac OS X. I use a Kensington presenter clicker to advance the images to change them remotely. I drop new images into a Google Drive folder from another Mac, which the picture frame automatically picks up and puts into the image rotation. And if I want to make major changes, I just use a wireless keyboard and mouse to work on the frame like I would a normal iMac. It is very unsophisticated.

Re: A Canvas Made of Pixels

#107

Post by claybavor »

KingMob wrote: post #60

Thisi s cool, but to really reproduce art, you have to avoid RGB-based displays. I've always assumed the reason wide-gamut/CIE L a b*-influenced displays are uncommon is that RGB is "good enough" for most purposes outside of image-editing/printing. But they can only show a fraction of the colors humans can see. IIRC, the standard sRGB space used in most monitors can only show a third of the human-visible spectrum.

Yes! What I really want for a future version of this is a 12-bit color depth, HDR, 8K OLED monitor, so you get true blacks, great resolution, and very accurate color reproduction across a very wide dynamic range. Maybe in a few years.

Re: A Canvas Made of Pixels

#108

Post by claybavor »

Tinyyy wrote: post #10

Wow this is incredibly cool! I love the shy feature especially, to screw with the viewer :P One question I have, though, is that since the aspect ratio of the screen is fixed, does that mean that all the photos have to be rescaled? That is kinda inelegant, I wonder if there's a way to fix it.

Yes, I have to crop the images to the aspect ratio of the display. I considered doing a simulated digital mat which could change given the aspect ratio of the work being shown, but it wasted so much of the display that it was not worth it.

I end up not having to crop much, because the aspect ratio I chose lines up pretty well with those of many good paintings and photographs.

Re: A Canvas Made of Pixels

#109

Post by alok-g »

peter303 wrote: post #59

Constrast is the lagging factor in good computer displays. These are called High Dynamic Range (HDR) displays. The claim is the eye can see a contrast factor of about a million at any one time, and a billion switching between sunny daytime and darkest night. An end-to-end camera-display system would need 20 bit amplitudes represent such a dynamic range. Many current systems are just 8 or 12 bits. SIGGRAPH often exhib…

https://en.wikipedia.org/wiki/Human_eye#Dynamic_range

>> 4K resolution is close to what the eye can see.

Depends on the distance to the display (whose resolution is independent on where the viewer is).

Re: A Canvas Made of Pixels

#110

Post by soared »

martinpw wrote: post #99
soared wrote: post #47

Earlier quoted context omitted.

I just posted this in another comment, but M$ research has awesome foveated rendering: http://research.microsoft.com/apps/pubs/default.aspx?id=1766...

I got a live demo of this at a conference a few years back. There was a line to see the demo, so I first waited while others did it. They first showed the full resolution image, then enabled the foveated rendering. The latter looked terrible - a tiny patch of hires imagery and a massive blur for everything else. When it was my turn, they started with the full resolution image. I was waiting for them to enable the fov…

I'm so glad to hear this! Do you know of any progress since then? That very closely reminds me of my first time trying VR (last week). I sat and watched on the 2D monitor someone else doing it, and thought it looked incredibly stupid. Then I put on the headset..
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