Author Topic: Just because technology can do something, doent meant its always right  (Read 24767 times)

0 Members and 1 Guest are viewing this topic.

Offline tooki

  • Super Contributor
  • ***
  • Posts: 13157
  • Country: ch
Re: Just because technology can do something, doent meant its always right
« Reply #100 on: June 20, 2022, 07:27:09 pm »

Of course it doesn't care; the photo-chemistry is the same.

My suspicion is based on looking at the single frame of 70mm film in my possession.
So not even a representative sampling, or even a non-representative selection, but one single frame? That’s completely useless for the purposes of drawing conclusions, especially as broad (and goofy) ones as you’re making.

Quote
Anyhow, at least today, the only remaining manufacturer of motion picture film, Eastman Kodak, makes 65mm camera film* in the same ISOs as 35mm: 50, 200, 250, and 500. (Observe that none of these come even distantly close to the high ISOs modern digital cameras can capture cleanly.) The data sheets (one per film speed) — and thus the specs — are identical for all film sizes it comes in, from 8mm through 65mm.

As an aside, no wonder 70mm movies are so rare, and 60fps 70mm even rarer: at 24fps, a 1000 foot reel’s runtime is just under 9 minutes and costs around $1500, according to the price list I’m looking at. So at 60fps, that’s just three and a half minutes! (35mm is less than half the cost.) The intermediate film is even more expensive, but print film is massively cheaper.

*camera and intermediate films are 65mm, print film is 70mm.

Thanks for the hard numbers. It appears that my suspicion was pretty accurate, despite your snide comment.

For my 35mm stereoscopic slides I had to use 64ASA film, in order to minimise[1] the visible grain. Only one speed you mention is slightly slower (~1.3 times) than that, the others being ~3, ~4, ~8 times faster.

One day perhaps I'll digitise them to try to see the relative grain size.
Nothing —nothing — there supports your claim, which, to preempt any goalpost shifting, was that 70mm film uses a coarser grain than 35mm. That’s ridiculous. First of all, you don’t have a representative sample of different film types. Second, visible film grain depends not only on the film stock, but how it was shot and processed. (If you push process it to use it as higher ISO than it is, you get more grain.) Third, did you not notice the part about the SAME films being available in 35mm (as well as 8 and 16mm)? The fact that you have a sharp low-ISO piece of (still) photographic film doesn’t tell us anything. There is also high-ISO photo film that sacrifices resolution for sensitivity. Additionally, you’re comparing slide film to motion picture film, which is negative. (So your movie film is, by definition, at least one generation older than a slide, though typically far more generations removed.)

Nothing about your comparison results in anything remotely approaching a valid conclusion.
« Last Edit: June 20, 2022, 07:28:57 pm by tooki »
 
The following users thanked this post: bd139

Offline Simon

  • Global Moderator
  • *****
  • Posts: 18118
  • Country: gb
  • Did that just blow up? No? might work after all !!
    • Simon's Electronics
Re: Just because technology can do something, doent meant its always right
« Reply #101 on: June 20, 2022, 08:40:23 pm »
Interested to see where monitor tech goes. I have a 27” 4k and a 27” 5k next to each other and the 4k one looks horrible now. More pixels really does help with text sharpness and eye strain.

well you will have to find out what the human eye can actually resolve to convince me. I can't remember the equivalent PPI but we are practically at that of printed matter. OK 4k/5k maybe but 8k? nah.
 

Offline Simon

  • Global Moderator
  • *****
  • Posts: 18118
  • Country: gb
  • Did that just blow up? No? might work after all !!
    • Simon's Electronics
Re: Just because technology can do something, doent meant its always right
« Reply #102 on: June 20, 2022, 08:47:06 pm »
Yes and as soon as you move further away your screen gets bigger. I have a 42" monitor and 27" monitors. Both 4k, both look the same because I sit as close as 0.5m from the 27" ones but will be about 1.5m from the 43" one. The eye has an angle of view, The pixels actually take up an angle of our vision so it is about angular resolution. if we can see 150 degrees across and want a 4k monitor that is 150/4k gives you the angular resolution. That is fixed because we will always change our distance from the monitor based on it's size unless you are like my ex colleague with eye sight problems that had a 32" and put his eyes up to it with enlarged text.

My point was about TV, not computer monitors, and in conditions where they cannot change the distance.

Hence your statements, while correct, do not refute the two differing reasons for interest in HDTV when it was being developed.

Yes because whatever the size, increasing resolution works the same. The screen will be sized to the distance you sit from it, or you will view at a distance to suit the screen. I am of course omitting the case in the UK where we express our net worth in the size of screen we put in our living rooms only to watch anything like it is a tennis match :).

A low resolution will always look bad. At a certain increased resolution you will stop seeing the difference once it exceeds the resolving capability of your eyes.
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 23099
  • Country: gb
Re: Just because technology can do something, doent meant its always right
« Reply #103 on: June 20, 2022, 08:51:48 pm »
Interested to see where monitor tech goes. I have a 27” 4k and a 27” 5k next to each other and the 4k one looks horrible now. More pixels really does help with text sharpness and eye strain.

well you will have to find out what the human eye can actually resolve to convince me. I can't remember the equivalent PPI but we are practically at that of printed matter. OK 4k/5k maybe but 8k? nah.

Well the thing is the human visual system is a little more complex than throwing a PPI at it. That's just a projection onto a 2d plane. Firstly the resolution in your eyes is much larger in a smaller area and lower in peripheral vision. On top of that the brain fills in a chunk of information as it sees fit so the perception model needs to be considered too.

The human eye needs to be able to focus on any part of the screen and you need to consider the best case vision so the worst case has to be used. Add to that the worst case distance and focal plane and you're talking about 576 megapixels worth of resolution (quoting the Roger M Clark figure).

8k is ~ 33MP so there's a long way to go to 576MP. And you need to consider the size, focal plane etc within that.

At the edges, there's absolutely bugger all resolution in your eyes and the brain fills all the shit in which is why the RGB back lit TVs work so well with a few pixels.

Add the whole film grain discussion to this, thinking how the grain is perceived, and there's a shit load of resolution required worst case and a whole load of personal perception and terribly eyesight warping it into generalisations.

But this is mostly used to display art which is a corrupting and highly subjective influence as well!
« Last Edit: June 20, 2022, 08:54:15 pm by bd139 »
 

Offline Simon

  • Global Moderator
  • *****
  • Posts: 18118
  • Country: gb
  • Did that just blow up? No? might work after all !!
    • Simon's Electronics
Re: Just because technology can do something, doent meant its always right
« Reply #104 on: June 20, 2022, 09:05:48 pm »
Don't know what you mean by focal plane, yes we see with the centre of our eyes the most, I think from memory it is something like a 1.5 degree angle that has most of the ability with the rest being peripheral vision or pieced together and yes all of the screen needs to be of a resolution that the centre of the eye cannot see the pixels but what is that resolution? (angular resolution will do as it will be agnostic to the screen size/distance)
 

Online 2N3055

  • Super Contributor
  • ***
  • Posts: 7466
  • Country: hr
Re: Just because technology can do something, doent meant its always right
« Reply #105 on: June 20, 2022, 09:11:09 pm »
Don't know what you mean by focal plane, yes we see with the centre of our eyes the most, I think from memory it is something like a 1.5 degree angle that has most of the ability with the rest being peripheral vision or pieced together and yes all of the screen needs to be of a resolution that the centre of the eye cannot see the pixels but what is that resolution? (angular resolution will do as it will be agnostic to the screen size/distance)

https://www.eevblog.com/forum/chat/just-because-technology-can-do-something-doent-meant-its-always-right/msg4249858/#msg4249858

That is actually measured by scientists...
"Just hard work is not enough - it must be applied sensibly."
Dr. Richard W. Hamming
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 23099
  • Country: gb
Re: Just because technology can do something, doent meant its always right
« Reply #106 on: June 20, 2022, 09:13:50 pm »
Don't know what you mean by focal plane, yes we see with the centre of our eyes the most, I think from memory it is something like a 1.5 degree angle that has most of the ability with the rest being peripheral vision or pieced together and yes all of the screen needs to be of a resolution that the centre of the eye cannot see the pixels but what is that resolution? (angular resolution will do as it will be agnostic to the screen size/distance)

https://www.eevblog.com/forum/chat/just-because-technology-can-do-something-doent-meant-its-always-right/msg4249858/#msg4249858

That is actually measured by scientists...

No they're wrong. Because at greater than 1m I can clearly tell the difference between the 4k and a 5k 27" screen at 157dpi and 218dpi which I sit in front of every day.

If I open the full London connections tube map to 1/4 of each screen in a PDF, I can read the station names on the 5k but not on the 4k. The information isn't even there on the 4k. On a 1440p screen I'd probably have to have it full screen.

Also there's no citation or conditions for your information. Perhaps that's an AVERAGE across the entire eye. Within the focal centre there might be 50x the resolution of 0.3mm and that's what is important.

Edit: here's a 14.2" 3024x1964 screenshot with the tube map at 254ppi which is 60-70cm away from me.

I can read the station names fine! (I have above average eyesight for ref)

« Last Edit: June 20, 2022, 09:21:19 pm by bd139 »
 

Online tom66

  • Super Contributor
  • ***
  • Posts: 7335
  • Country: gb
  • Electronics Hobbyist & FPGA/Embedded Systems EE
Re: Just because technology can do something, doent meant its always right
« Reply #107 on: June 20, 2022, 09:20:42 pm »
Anyone who claims they can resolve anything better than 4K should try one of these test patterns that I just made in Python.  If displayed at 1:1 at the normal viewing distance of your monitor, you should be able to see pixels if a higher resolution would benefit you.  If you can only see grey, then further resolution will provide no advantage.  I can only *just* see the pixel pattern, but it's mostly grey to me, so at best I would estimate I *might* benefit from 5K, but beyond would be pointless. 

Interestingly enough using the checkerboard pattern on my Samsung monitor results in a green tint to the image.  I suspect this is caused by the excessive current that this pattern draws.  I can see the rows around this pattern are darker, and they get darker and the pattern gets greener the more column space it covers.  It shows one limitation of LCD technology.  A high number of transitions implies large capacitive drive current (as the column drivers will be alternating to drive each pixel, and the row drivers will have to conduct this current.  The panel is scanned vertically, so each column driver will have to swing between Vcom and Vdd or GND depending on the subframe.)  I suppose this means in theory there are some images, which if displayed for some time, could shorten the life of a panel, as the chip-on-flex drivers are usually non-replaceable. 

I recall owning a Panasonic plasma TV that would detect this specific pattern and begin to dim the panel after about 5 seconds to prevent the address drivers from overheating:  those chips had to swing from 75V to 0V and back again at a rate of several MHz, and a typical 1920-wide panel would feature 5760 channels on custom chip-on-flex drivers with minature heatsinks.  Now that's power semiconductor design :)  (It's one of these chips that killed Dave's old Panasonic PDP, but it must be said that failures are rare!) 
« Last Edit: June 20, 2022, 09:22:43 pm by tom66 »
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 23099
  • Country: gb
Re: Just because technology can do something, doent meant its always right
« Reply #108 on: June 20, 2022, 09:22:54 pm »
It's more complicated than test patterns. The representation of text and how the eye perceives it is what you are paying for.

Compare an inkjet printout to a decent laser printer printout and you'll see what I mean.
 

Online tom66

  • Super Contributor
  • ***
  • Posts: 7335
  • Country: gb
  • Electronics Hobbyist & FPGA/Embedded Systems EE
Re: Just because technology can do something, doent meant its always right
« Reply #109 on: June 20, 2022, 09:29:21 pm »
It's more complicated than test patterns. The representation of text and how the eye perceives it is what you are paying for.

Compare an inkjet printout to a decent laser printer printout and you'll see what I mean.

I disagree.  If you can't see the pixels then fundamentally it doesn't matter what your brain does with the information, everything beyond that is interpolation on data that is there at any resolution beyond the maximum fidelity of your optic system.
 

Offline BrianHG

  • Super Contributor
  • ***
  • Posts: 8275
  • Country: ca
    • LinkedIn
Re: Just because technology can do something, doent meant its always right
« Reply #110 on: June 20, 2022, 09:51:55 pm »
It's more complicated than test patterns. The representation of text and how the eye perceives it is what you are paying for.

Compare an inkjet printout to a decent laser printer printout and you'll see what I mean.

I disagree.  If you can't see the pixels then fundamentally it doesn't matter what your brain does with the information, everything beyond that is interpolation on data that is there at any resolution beyond the maximum fidelity of your optic system.
This is only true is the so called pixels arent fixed squares, like on monitors.
All you need is a 1.5 - 2.5 pixel thick line at off-axis angles, like 5 degree, or 85degree, (common in fonts) viewed on a 4k screen, then jumping to an 8k screen where those angled lines are now constructed with 3-5 pixels of width to easily see how much more comfortable it is on the eye, even if you cant see the individual pixels which make up the edges of that line.

This is coming down to those who have used such hi-res monitors to do actual work (video doesn't count) and those who haven't.  The text reads far superior when it is constructed from pixels at least 4x smaller that what your eye can perceive when you have a pattern of lines, 1 pixel on, 1 pixel off.

Our eye are analog.  We need an over sampled source to achieve comfort for varying thickness combined with angular drawings where sharp contrast exists.
« Last Edit: June 20, 2022, 10:01:26 pm by BrianHG »
 

Offline SiliconWizard

  • Super Contributor
  • ***
  • Posts: 15797
  • Country: fr
Re: Just because technology can do something, doent meant its always right
« Reply #111 on: June 20, 2022, 10:05:06 pm »
Yep.

Vision (and our other senses) is more complicated than just seeing individual "pixels" or "units" of images.
In the same vein, while we can't differentiate with our audition two frequencies that are two close to one another, when presented separately, if we just mix them, we'll hear a beating, so we are able to tell  there just isn't a single frequency. Similar things happen with vision, and through a lot of "parallel processing", our nervous system is able to discriminate several simultaneous stimuli as "contrast" much finer than as single stimuli.

Now while this is a general consideration, no two people have the same eyesight, be it purely from the optics of our eyes, up to the retina, and then the cerebral structures, so I'm pretty sure while some people can definitely tell a difference from a Full HD and 4K screen the typical size of a TV set at say 3-4 meters, or even between 4K and 8K, some others may not even be able to see a difference between SD and Full HD. So never assume that your particular experience here can be generalized.
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 23099
  • Country: gb
Re: Just because technology can do something, doent meant its always right
« Reply #112 on: June 20, 2022, 10:13:02 pm »
So never assume that your particular experience here can be generalized.

Exactly so you have to build for the best or the worst case depending on your user. Which 8k covers. Which is why it exists. I'm sure 16k will have some value on larger screens as well.
 

Online tom66

  • Super Contributor
  • ***
  • Posts: 7335
  • Country: gb
  • Electronics Hobbyist & FPGA/Embedded Systems EE
Re: Just because technology can do something, doent meant its always right
« Reply #113 on: June 20, 2022, 10:14:20 pm »
If that were true, it could be trivially improved by antialiasing, which is further improved by subpixel antialiasing, a function of most modern text rendering libraries.

I however remain unconvinced.  My hypothesis is:  If the test patterns above appear grey, or nearly grey with only mild high frequency content, you have effectively found the high-pass filter frequency for your optic system.   You will not be able to perceive much more than this and there is no further benefit to additional pixels.   You can improve the appearance of the pixel grid by antialiasing, to avoid the sharp cutoff effect, but that merely seeks to redistribute the energy in a bandlimited system.

I remember having a debate along these lines with a friend of mine when working on an oscilloscope project.  It was based on whether antialiasing (display) would benefit the appearance of an intensity-graded oscilloscope.  I contented that you would not want to antialias the vectors that form the waveform, as the ultimate density information comes from the histogram of display data.  In fact, antialiasing would probably worsen the image somewhat as it would spread the information out further from the ideal distribution, which is an infinitely sharp band-pass filter for each column of data.

And while the eye is not a pixel camera, the density of retinal cells in the centre FOV is remarkably consistent, measurable as an angle of arc, and while not gridlike, it has a relatively consistent arrangement.  The notable exception is for chrominance, as we know that cone cells are distributed more chaotically.  (But that's why we use chroma subsampling, and whether people can reliably tell 4:2:2 and 4:4:4 apart for photographic tests is another interesting debate...)
« Last Edit: June 20, 2022, 10:16:36 pm by tom66 »
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 23099
  • Country: gb
Re: Just because technology can do something, doent meant its always right
« Reply #114 on: June 20, 2022, 10:18:04 pm »
Anti-aliasing is only a perception hack for low resolution displays. Compare laser printed 1200dpi text is not anti-aliased.

Eventually the objective is to build displays where anti-aliasing is unnecessary.

Edit: technically anti-aliasing allows for more precise perceived positioning of glyphs in relation to each other and the representation of curves because it's quite jarring when they are discretised to pixel boundaries. If you throw enough pixels out there the problem goes away. Typography is a somewhat complex area to move into here as well. If you're looking at a photo, things are different!
« Last Edit: June 20, 2022, 10:22:15 pm by bd139 »
 

Online tom66

  • Super Contributor
  • ***
  • Posts: 7335
  • Country: gb
  • Electronics Hobbyist & FPGA/Embedded Systems EE
Re: Just because technology can do something, doent meant its always right
« Reply #115 on: June 20, 2022, 10:22:39 pm »
Exactly, it's a hack that makes a lower resolution display appear prettier and more comfortable to view, by distributing the higher frequency information across adjacent pixels and making the sharp edges more comfortable to look at.

But once you go over the resolution limit of the optic system, its irrelevant.  It is all in the rolloff, which at least for me appears somewhat only very slightly past 4K resolution. YMMV, but I doubt anyone that has 20-20 vision will be much different.

I cannot see any need for 16K, except for 120"+ displays.  Even in a cinema, I would have thought 8K would be approaching the optics limit.  My 4K monitors fill, I would say, about 60% of my optic field.  If we assume that the limit is 5K based on my test, and we want to fill 100% of the visual field, like a cinema screen, then we would cap out around 8-9K.  Obviously, everyone has different experiences, but I can't say I can perceive the resolution at my local cinemaplex which advertises that it uses RGB DLP 4K projectors.
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 23099
  • Country: gb
Re: Just because technology can do something, doent meant its always right
« Reply #116 on: June 20, 2022, 10:27:51 pm »
Yep.

Cinema, photography and video probably doesn't matter past 8k unless the screen is huge. For most, 4k is probably fine. I'm quite happy with it for video.

However text, line art and information presentation is another thing. One reason paper looks so good is the resolution and dynamic range is pretty damn high. Which is why we need to build better monitors. Might as well get free TVs while we're at it out of the panels.

Actually no it works the other way round. People buy pointless TVs and this drives the panel price down and eventually we get nice monitors for a reasonable price. Although reasonable price seems to have stopped at 4k which is sad.
 

Online magic

  • Super Contributor
  • ***
  • Posts: 7453
  • Country: pl
Re: Just because technology can do something, doent meant its always right
« Reply #117 on: June 21, 2022, 05:59:32 am »
This thread reminds me much of audiophoolery.

It will become 10 pages of "debate" about the limits of vision and virtues of "analog smoothness", and not a single result of an actual blind test will be presented, whether carried out by you or by anyone else :P
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 23099
  • Country: gb
Re: Just because technology can do something, doent meant its always right
« Reply #118 on: June 21, 2022, 06:10:19 am »
Unlike audiofoolery this is very well defined and isn’t a niche market so I’m not sure what your point is?
 

Online magic

  • Super Contributor
  • ***
  • Posts: 7453
  • Country: pl
Re: Just because technology can do something, doent meant its always right
« Reply #119 on: June 21, 2022, 06:34:44 am »
Yes, it's very well defined by "I can clearly see a difference" and "I can clearly prove that you can't" :-DD
 
The following users thanked this post: tom66

Online ebastler

  • Super Contributor
  • ***
  • Posts: 7375
  • Country: de
Re: Just because technology can do something, doent meant its always right
« Reply #120 on: June 21, 2022, 06:39:12 am »
Well, the "analog vs. digital photography" part of the debate certainly has audiophoolery potential: The different "feel" of a grainy film image vs. the "cold perfection" of digital images and so on.

We were drifting into that territory for a while, with reference to old filmmakers who can't be wrong and know that "film is always better". But the discussion has moved back into the more well-defined realm of pixel counts and angular resolution of the eye afterwards.
 
The following users thanked this post: tooki

Offline bd139

  • Super Contributor
  • ***
  • Posts: 23099
  • Country: gb
Re: Just because technology can do something, doent meant its always right
« Reply #121 on: June 21, 2022, 06:41:54 am »
Yes, it's very well defined by "I can clearly see a difference" and "I can clearly prove that you can't" :-DD

Give me a double blind test, with text and I will demonstrate by ability to discriminate between different PPI displays perfectly beyond your assumptions.

I actually have done this recently before I spent a kidney on a 5k display.
 

Offline BrianHG

  • Super Contributor
  • ***
  • Posts: 8275
  • Country: ca
    • LinkedIn
Re: Just because technology can do something, doent meant its always right
« Reply #122 on: June 21, 2022, 06:53:10 am »
There is certainly a difference on good old Protel99SE between a 2k and 4k display.
A huge difference on net label size and fine traces.
 
The following users thanked this post: tom66, bd139

Online tom66

  • Super Contributor
  • ***
  • Posts: 7335
  • Country: gb
  • Electronics Hobbyist & FPGA/Embedded Systems EE
Re: Just because technology can do something, doent meant its always right
« Reply #123 on: June 21, 2022, 07:29:42 am »
Vivado (ILA especially) and schematic editing in 4K look great.

I still contend that >= 5K is going to be of little benefit for a PC monitor.
 

Offline Psi

  • Super Contributor
  • ***
  • Posts: 10385
  • Country: nz
Re: Just because technology can do something, doent meant its always right
« Reply #124 on: June 21, 2022, 07:40:10 am »
One thing to consider is that people are not all the same.
Some people may not see the ocular detail that others can, and if people assume everyone else must 'see' the same as they do, then you will always get pointless arguments.
Greek letter 'Psi' (not Pounds per Square Inch)
 
The following users thanked this post: bd139


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf