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01-22-2014, 11:19 AM   #31
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QuoteOriginally posted by gazonk Quote
My point is that maybe you can get both.
Please, read my post again.

Then you may see my point which was that MF lenses have higher fstop, i.e., aren't any wider than 35mm full frame, i.e.. there can't be any low light benefit of MF over FF. Except Pentax releases a new kind of MF lens, like 85/1.4 for MF.

01-22-2014, 11:22 AM   #32
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QuoteOriginally posted by Rondec Quote
The 645D does seem to do a better job with reds, for whatever reason, even as compared to cameras like the D800.
Source?
Not according to lab tests.
One thing I notice is people both overexpose (clip the red channel) and use uncalibrated color profiles. Therefore, I tend to ignore simple "user experience" on the matter.
Same goes for Nikon colors vs. Canon colors (which is a more substantiated differentiation wrt lab tests though: Canon color filters use a larger spectral overlap where Pentax is more like Nikon).

However, I have a side note to add to my above consideration:

The spectral response curve for CMOS and CCD is, in a first order approximation, the same as for silicon crystals. This seems to hold true for CCD. For CMOS it is reported that due to a flatter structure of the photo diode, the peak of the spectral sensitivity (–900nm) can be shifted down to 600nm (longer wavelength have deeper penetration depth). This may indeed have a noticeable impact on the color rendition of a sensor if the color matrix isn't modified to cope with that.

However, I assume that more recent high quantum efficiency CMOS sensors have comparable penetration depth to CCD as otherwise I don't see them match the quantum efficiency for astro CCD (which they do). So, I can imagine that early CMOS sensors had a different color rendition indeed (should show up in lab tests too) but that this difference may be a thing of the past.

Last edited by falconeye; 01-22-2014 at 11:41 AM.
01-22-2014, 11:41 AM   #33
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QuoteOriginally posted by falconeye Quote
Source?
Not according to lab tests.
One thing I notice is people both overexpose (clip the red channel) and use uncalibrated color profiles. Therefore, I tend to ignore simple "user experience" on the matter.
Same goes for Nikon colors vs. Canon colors (which is a more substantiated differentiation wrt lab tests though: Canon color filters use a larger spectral overlap where Pentax is more like Nikon).
Just what I saw in the Imaging Resource RAW files comparing 645D to the D800.
01-22-2014, 11:48 AM   #34
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QuoteOriginally posted by H. Sapiens Quote
Yeah, it can be hard to decide on the right combination of wood and leather when all the internals are wired and ready to go.
lol

01-22-2014, 11:56 AM   #35
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QuoteOriginally posted by Pioneer Quote
I much prefer the the CCD sensor color output. It may not be as noise free at high ISO, but it is certainly a much richer color and I love that.
Is this really true, though? If so, how is that measured/proven? The color bit depth measurements on DxOmark don't suggest this.

It could be true, I just have heard it mentioned in various ways but have never seen a definitive finding published that backs it up.

EDIT: never mind falk addressed
01-22-2014, 12:06 PM - 1 Like   #36
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My interpretation

QuoteOriginally posted by falconeye Quote
Please, read my post again.

Then you may see my point which was that MF lenses have higher fstop, i.e., aren't any wider than 35mm full frame, i.e.. there can't be any low light benefit of MF over FF. Except Pentax releases a new kind of MF lens, like 85/1.4 for MF.
I suspect they were talking about 'better than previous versions of MFD bodies', not 'better than FF'. The original 645D performed worse regarding noise than current FF with equivalent lenses, now it's (presumably) equalized and a MFD shooter will 'get both' resolution and better low-light performance than before, using the same lenses as before.
01-22-2014, 12:14 PM   #37
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QuoteOriginally posted by jsherman999 Quote
I suspect they were talking about 'better than previous versions of MFD bodies', not 'better than FF'. The original 645D performed worse regarding noise than current FF with equivalent lenses, now it's (presumably) equalized and a MFD shooter will 'get both' resolution and better low-light performance than before, using the same lenses as before.
A major problem in practice is that there just aren't that many fast lenses on cropped-645. If Pentax brought out a 'fuller-frame' 645 some of that discrepancy would be erased, and of course you'd still have the other benefits of the larger sensor, both theoretical (resolution) and practical (resolution, better VF, etc).

I expect/hope the 645II will trounce the 645 and eliminate/reduce some of the downsides of the 645 (frame rate, slower lenses, etc).
01-22-2014, 01:09 PM - 1 Like   #38
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In any case, this is all good news !

CCD or CMOS is not fundamental for MF photog as i have experienced, it is such a pleasure to look through their exceptionnal view-finders...

Secondly, i do much prefer large photosites to hyper-resolution, and appreciate that global resolution is kept at a good level (50 Mpix is high resolution still, though not "stratospheric"), allowing for excellent DR and reduced diffraction preserving the very aim of medium format : excellent IQ whatever closed the diaphragm is...

EDIT : please let's avoid FF versus MF debate... even through max. aperture : this is just non-sense...


Last edited by Zygonyx; 01-22-2014 at 01:15 PM.
01-22-2014, 02:05 PM   #39
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QuoteOriginally posted by falconeye Quote
Please, read my post again.

Then you may see my point which was that MF lenses have higher fstop, i.e., aren't any wider than 35mm full frame, i.e.. there can't be any low light benefit of MF over FF. Except Pentax releases a new kind of MF lens, like 85/1.4 for MF.
Come on, you're fighting straw men, it's probably your own FF obsession that makes you think that I wanted to compare FF to MF at all. I didn't. I just wanted to point out that we may get a new 645D with much better high ISO performance than the current model. The only reason I mentioned D600 at all was because the sensor may be similar.
01-22-2014, 04:35 PM - 1 Like   #40
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645II with 50MP.
No information if ccd or cmos.
Couple of weeks ago,internal Roadmap shows one new 645 lens for the next,near converter and Telezoom for 35mm System.

Best regards
01-22-2014, 04:54 PM   #41
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QuoteOriginally posted by asahi man Quote
one new 645 lens for the next,near converter and Telezoom for 35mm System.

Best regards
Thanks for the intel.

Did you intend that to read: "one new 645 lens for the next year, also a converter and telezoom for 35mm"?
01-22-2014, 11:04 PM   #42
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QuoteOriginally posted by falconeye Quote
I hear this often enough to reply. First, let me cite this post:
[source: There's no such thing as "CMOS color" or "CCD color": Open Talk Forum: Digital Photography Review ]
(I endorse the quoted content)

Second, let me refer to DxO's color analysis based on the raw output of K-5 and 645D (relaesed about the same moment in time):

K-5
645D
Both color responses are extremely similiar, with similiar metamerism index just close of 80 (anything above 80 is said to be indistinguishable from natural true colors). If anything, the 645D has a tad stronger red and blue diagonal color matrix elements (less overlap) which may lead to a bit more brilliat than natural colors if not corrected for by the raw converter profile.

Professionals (esp. studio product and fashion shooters) use inexpensive tools like X-Rite's ColorChecker Passport to calibrate their camera. After doing so, the DxO analysis tells us that no visible differences in color rendition should remain (maybe with one exception, red channel clipping for overexposed images which is 3% stronger with the K-5).

IMHO, there is no such thing as "CCD colors".
Thanks for your response Falconeye. I find this all very interesting. I guess I am going to have to pick up one of these color checkers to calibrate my cameras. At this point there is a clear difference in the color I get from the K10d versus the K5iis. Obviously the resolution advantage goes to the K5iis but the advantage goes the other way when I print. I have not used X-Rite Color Checker but I have done extensive work adjusting the color levels in camera and, so far, the K5iis still lags in this area.

However, I will be the first to admit that I have a lot to learn about this so I will certainly take your advice and continue to work on this using the tools you have suggested. Perhaps by the time I'm pushing up daisies I will have mastered some of this.

Thanks again.
01-23-2014, 01:24 AM   #43
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QuoteOriginally posted by Pioneer Quote
At this point there is a clear difference in the color I get from the K10d versus the K5iis.
I also see a difference (between K10d and K-5), and sometimes miss the K10d colors, but I have to admit the blue skies of the K10d were supernatural
01-23-2014, 07:34 AM   #44
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QuoteOriginally posted by jsherman999 Quote
I suspect they were talking about 'better than previous versions of MFD bodies', not 'better than FF'.
QuoteOriginally posted by ElJamoquio Quote
A major problem in practice is that there just aren't that many fast lenses on cropped-645.
QuoteOriginally posted by gazonk Quote
Come on, you're fighting straw men, it's probably your own FF obsession that makes you think that I wanted to compare FF to MF at all.
I thought the message was that medium format paired with a D600-level sensor would provide a superior low light tool. So I replied saying it's not and explained why. Maybe, a few others thought the same. I apologize otherwise.

btw, I am not FF obsessed, I am now shooting FF whenever I like which isn't always.

QuoteOriginally posted by Pioneer Quote
I have not used X-Rite Color Checker but I have done extensive work adjusting the color levels in camera and, so far, the K5iis still lags in this area.
I would be interested to hear about your experience when you do so. It may well be that you'll be less satisfied with K10D output after calibration. That would be an interesting exercise.

Unfortunately, tools like the ColorChecker use preregistered ISO colors which means, they cannot be used to make K-5 colors look like K10D's
01-23-2014, 09:53 AM   #45
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QuoteOriginally posted by falconeye Quote
I thought the message was that medium format paired with a D600-level sensor would provide a superior low light tool. So I replied saying it's not and explained why. Maybe, a few others thought the same. I apologize otherwise.
I said "This would make the 645D mk2 incredibly good in low light!" - and I stand by that statement, but I didn't mean to imply that it would be better than anything else.
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