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02-22-2015, 02:37 PM   #181
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Most glass is able to resolve more than 40lp/mm for 50% contrast, but much more for less than 50% contrast level. The D810 has 36 Mpixels, or 7360 x 4912 for 36x24, bayer sensor. 7360/36 =204 ; 204/3 = 68 pixels/mm for each primary color. This means that color artifacts are present; on top of color leakage color due to the fact that color filters are not perfect. I fully agree with Falk. And in my opinion, the pixel density of the K-3 is also welcome into a full frame camera.

02-22-2015, 08:22 PM   #182
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QuoteOriginally posted by biz-engineer Quote
Most glass is able to resolve more than 40lp/mm for 50% contrast, but much more for less than 50% contrast level. The D810 has 36 Mpixels, or 7360 x 4912 for 36x24, bayer sensor. 7360/36 =204 ; 204/3 = 68 pixels/mm for each primary color. This means that color artifacts are present; on top of color leakage color due to the fact that color filters are not perfect.
But for what percentage of the image circle does this apply? My concerns are largely about edge performance. Most glass degrades pretty significantly as you move away from the centre.
02-22-2015, 10:07 PM   #183
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QuoteOriginally posted by jonby Quote
But for what percentage of the image circle does this apply? My concerns are largely about edge performance. Most glass degrades pretty significantly as you move away from the centre.
Yes, exactly !!! Lenses usually have higher resolution in the center of the frame. Here the idea behind having a sensor that outresolve the lenses in the center is to avoid aliasing (moire patterns) in the center of the images , without having a loss of resolution applied to the whole frame by an optical AA filter. What could be is adaptive resolution, i.e smaller pixel pitch in the center and larger pixel pitch in the corners. However, this would be a custom design; more difficult to layout the sensor, and not necessarily adapted to all lenses. So , in the end, what manufacturers are doing is to boost the resolution in a uniform manner. That's what we see today, as long as the sensor resolution does not hit the diffraction limit of the lens , every increase in sensor resolution leads to better image quality.

Last edited by biz-engineer; 02-22-2015 at 10:13 PM.
02-23-2015, 07:45 AM   #184
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QuoteOriginally posted by jonby Quote
However, your point about the ability of this technique to reduce demosaicing and moire artifacts (and noise?) is a good one which I missed. This will be of benefit in a wider range of cases. I would certainly find these techniques more useful however, if the output size was still 36MP and not 4x or whatever - is this possible, do you think?
It's already an option in Olympus's implementation (the 16MP RAW), so I don't see why not?

02-23-2015, 07:51 AM   #185
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another data point: diffraction shows up generally a stop earlier in the center than on the edges. Thus when someone says: "x suffers from diffraction after f/8" they are unknowingly talking about the center. The edges can probably handle another stop before diffraction is noticeable.

YMMV

Michael
03-26-2015, 10:23 PM   #186
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New article on PR..
Ricoh revealed their new pixel/sensor shift technology (available with firmware update?) | Photo Rumors

Original source.. Imaging Resource..
http://www.imaging-resource.com/news/2015/03/23/in-progress-ricoh-reveals-pi...-coming-soon-t

Last edited by Tesla; 03-26-2015 at 11:04 PM.
03-27-2015, 07:28 AM   #187
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QuoteOriginally posted by MJSfoto1956 Quote
another data point: diffraction shows up generally a stop earlier in the center than on the edges. Thus when someone says: "x suffers from diffraction after f/8" they are unknowingly talking about the center. The edges can probably handle another stop before diffraction is noticeable.

YMMV

Michael
What is the physics that allows to write that ?

---------- Post added 03-27-2015 at 03:33 PM ----------

I agree with Falco, plus that the sensor shift of one pixel, should improve dynamic range, by 1,58 EV more or less
03-27-2015, 12:46 PM   #188
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QuoteOriginally posted by Scintilla Quote
It's already an option in Olympus's implementation (the 16MP RAW), so I don't see why not?
So on the Olympus, you can derive 16MP raws from the multi-shot mode with full colour info at every pixel? This hasn't been clear from what I have read, but if so, that would be a very useful option in a 36MP Pentax.

03-28-2015, 12:54 AM   #189
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It seems, so far that:

- Oly's version both permits full color informations AND better resolution from half pixels displacement. If it outputs more MPx files though, the question will be how much resolution you really gain vs file size (guys scanning negs know what I mean).

- Pentax version would allow full color information 'only' but by itself may up the res a bit.

Oly of course has more incentives to boost resolution, even only MP counts because they're stuck with their 'small' sensor.
Pentax doesn't care that much 'cos they have an FF (most probably 36MP) and MF (50MP) in their range.

Either way this is welcome tech IMO.
03-29-2015, 04:18 AM   #190
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QuoteOriginally posted by falconeye Quote
According to the thread title, we can discuss super resolution independently from what is said in an interview. After all, it is a pending topic for any vendor with sensor shift technology.

In that respect, I found the Olympus interview (linked on DPR page) very revealing. Asked why now, not earlier, they responded that only now the sensor shift has become accurate enough to support subpixel shifts (1Ám accuracy). And that this accuracy would be at the basis of the improved shake reduction efficiency too.

It may then be easy to conclude that superresolution and 4+ stops shake reduction efficiency are correlated. So, Pentax may first have to do some homework and improve the efficiency of their SR feature. It isn't yet on par with Olympus' achievements in this department.
Isn't all this covered in the old Ricoh/Pentax SR patent ? SR being done by electromagnetic floating sensor stage and moire reduction/pixel shifting by piezoelectric sensor movement separate from this ?

I'll go back to sleep again ...
03-29-2015, 04:31 AM   #191
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That's an old Ricoh patent, no relation to Pentax SR. And AFAIK, the AA simulator is using Pentax SR instead of a separate piezo-based mechanism.
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