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09-30-2014, 03:19 AM   #361
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QuoteOriginally posted by falconeye Quote
Doesn't make sense.
The best possible color sensor works with 3 color filters each replicating one of the three human eye's color sensitivities as close as possible. Might work for bee eyes though
How is it then that the eyes (I think?) are better at spectral violet than camera sensors? Just that the RGB filters don't quite emulate the human eye's R, G and B sensitivities? Or is it just the fabulous color temperature adjustment of our eyes+brain that does the trick?

09-30-2014, 06:02 AM   #362
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QuoteOriginally posted by gazonk Quote
How is it then that the eyes (I think?) are better at spectral violet than camera sensors? Just that the RGB filters don't quite emulate the human eye's R, G and B sensitivities?
With three filters, you only span a triangular color space.

But the eye's natural color space is more complicated.

Here's a simplified (repurposed) picture that gives some idea.
It's really way more complicated than that.
Also, remember that you see the picture on a screen,
which has its own limitations.

09-30-2014, 06:38 AM   #363
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QuoteOriginally posted by gazonk Quote
How is it then that the eyes (I think?) are better at spectral violet than camera sensors?
Is it so? If, then I would assume poor color filter spectra indeed. However, this stuff is measured when computing a camera's metamerism index. Like DxO does.

QuoteOriginally posted by lytrytyr Quote
With three filters, you only span a triangular color space.

But the eye's natural color space is more complicated.
It really is not.

E.g., cf. The Color-Sensitive Cones

It may however, be that an image's color space has a narrower gammut than the eye. Additionally, there indeed is complication at twilight where both rods and cones contribute to the human image perception. Because rods have another spectral sensitivity, cf. Brightness and Night/Day Sensitivity

But I assume we're not talking about twilight color spaces here ...

Last edited by falconeye; 09-30-2014 at 06:45 AM.
09-30-2014, 07:16 AM   #364
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QuoteOriginally posted by falconeye Quote
It really is not. E.g., cf. The Color-Sensitive Cones
From what I understand (no expert here!),
the green channel works in the opposite direction to the red and blue channels
(overall, excitatory rather than inhibitory),
hence the bulge of the color space in the green direction.

09-30-2014, 06:46 PM   #365
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Sony is Doomed = 28,800
And I believe that something will happen with Sony Image if nothing improve in 2015. Would not be surprised if they sell it to Fuji or Ricoh !!!
09-30-2014, 09:42 PM - 1 Like   #366
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QuoteOriginally posted by bobmaxja Quote
And I believe that something will happen with Sony Image if nothing improve in 2015. Would not be surprised if they sell it to Fuji or Ricoh !!!
You just won the Crazy Internet Comment of the Day award!
09-30-2014, 11:10 PM   #367
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As falconeye said, the best would be a sensor able to measure directly photon wavelength. But for each photosite, you need as a result, an histogram of photons captured with their individual wavelength. I Wonder if such a physical device will be feasible and if there is R&D on it.
10-01-2014, 05:10 AM   #368
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QuoteOriginally posted by goubejp Quote
I Wonder if such a physical device will be feasible and if there is R&D on it.
Sure, ask CERN. It's just a big heavy for most pockets

But there is research on pixels measuring single photon events (a binary event). That would be a prerequisite to measure their wavelength or energy, e.g. by measuring the energy of the converted electron.

However, there is no benefit to this over a conventional color filter (except for quantum efficiency). Because you still would have to weight the histogram with the human response curves for RGB and thereby discarding many events. Resulting in just three figures for RGB. Once you use color filters replicating the human response curves close enough.

---------- Post added 01-10-14 at 13:18 ----------

QuoteOriginally posted by lytrytyr Quote
From what I understand (no expert here!),
the green channel works in the opposite direction to the red and blue channels
(overall, excitatory rather than inhibitory),
hence the bulge of the color space in the green direction.
I don't know what you mean.

If it is about the kind of signal coming out of the cones, rods, or retina, then this is irrelevant. It is part of the dataprocessing in the eye which actually is part of our brain. We don't actually see pixels but a few predefined patterns to start with. Again, irrelevant here.

We just need to replicate the OPTICAL stimulus to the eye, nothing else. After all, it is our very eye which will view the final result, either screen or print.

You would be correct though if you find a method to telephatically transmit images right into the visual cortex

10-01-2014, 06:34 AM   #369
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QuoteOriginally posted by falconeye Quote
You would be correct though if you find a method to telephatically transmit images right into the visual cortex
What do we think the visual cortex would do with this information? - my guess is convert it back to something recognizable in normal human perception.
10-01-2014, 08:14 AM   #370
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QuoteOriginally posted by falconeye Quote
I don't know what you mean.
By "green, red or blue channel",
I mean the way the brain responds to a viewed area of the given color.

Apparently, the overall response to green
is different to the overall response to red and blue.

Technically, that is seen by the green bulge in the color chart.

Biologically, it is sometimes interpreted as an evolutionary response
to the predominance of green in many natural environments.
10-01-2014, 08:22 AM   #371
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QuoteOriginally posted by falconeye Quote
Sure, ask CERN. It's just a big heavy for most pockets
I also have to inform you that it doesn't come in 50 different colors.
10-01-2014, 09:19 AM   #372
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QuoteOriginally posted by Digitalis Quote
I also have to inform you that it doesn't come in 50 different colors.
That kills it for me, so forget it.
10-01-2014, 09:21 AM - 1 Like   #373
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QuoteOriginally posted by Digitalis Quote
I also have to inform you that it doesn't come in 50 different colors.

10-01-2014, 11:32 AM   #374
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QuoteOriginally posted by bobdobbs Quote
You just won the Crazy Internet Comment of the Day award!
Bob mate, crazy comment er I do not think so, Sony is broke and has been hemoraging money on a grand scale for the last five years !!!, losses to date must reach near a billion dollars, yes dollars, some one will step in sooner or later, cameras make money its the television arm that's loosing the cash, my candidates for a takeover would be Toshiba or Hitachi.
10-01-2014, 12:00 PM   #375
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QuoteOriginally posted by Snappertim Quote
Bob mate, crazy comment er I do not think so, Sony is broke and has been hemoraging money on a grand scale for the last five years !!!, losses to date must reach near a billion dollars, yes dollars, some one will step in sooner or later, cameras make money its the television arm that's loosing the cash, my candidates for a takeover would be Toshiba or Hitachi.
It seems like it would make sense to sell the television business.
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