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very interesting results  :o

I already knew 24-70mkII is excellent lens, but I'm very excited about results on A7R. One think I'd like to ask is AF performance. You already mentioned AF is slow, but both pictures look spot on. Were there no trouble with missed focus? Especially handheld?
Canon EF24-70F/2.8 M2 AF with Metabones M3 adapter on a7R is slow but accurate.
I had no missing shots at all.
In fact Metabone focusing algorithm is very simple but solid:
It takes two passes from - to + calibrating lens and finding AF peak  and then goes back and does final move to the lens focus peak
I think that ultimate  resolution power of Canon EF24-70F/2.8 M2 help much in this process as focus peak could be easily detected by contrast AF system. With blurry lenses this would be a bit more difficult

Some more interesting test  results

Canon EF24-70F/2.8 M2  on Canon 1Dx body compared to Sony Zeiss 24-70 f/4 OSS on a7R body

 Again two 100% crops , no adjustements, a7R crop when exported from C1 to JPEG was downscaled to 1DX resolution.
No worry abot handheld as shutter speed in both cases is around 1/1600 so camera vibration does not  affect results

 At 24 mm images looks close to each other though Canon EF24-70F/2.8 M2  on Canon 1Dx perceptually looks a bit better. When 1Dx image upscaled to a7R resolution  the a7R image resolution difference is visible but perceptually  1Dx image overall is still slightly better to me eye

At 70mm   Canon EF24-70F/2.8 M2  on Canon 1Dx  is significantly better than Sony Zeiss 24-70 f/4 OSS and this difference is very obvious.

  This results just illustrates the point that the sensor resolution is only part in overall system performance. If lens is mediocre then even  image from higher resolution sensor  is less quality than from sensor with twice less resolution but using high quality optic.
These test actually correleate with DXOMark measurement results fo both lenses.

   I think it might also be interesting to compare image quality of  Canon 1Dx with Canon EF24-70F/2.8M2  to that of  Sony a7R with Sony Zeiss 24-70mm-F4-ZA-OSS - which would  be more pleasant to the eye perceptually.
Which system will win ???

Wow, now I feel better about the money I spent on it and I'm more confident about how it will work on a high MP sensor in the future.  Thanks for the test.
Yes, it was also WAW for myself.

I  was expecting to see some  difference between them  but no to such huge extent.
   Pictures taken using Canon EF24-70F/2.8M2 looks like pictures taken by MF system  - not only razor sharp up to single pixel on a7R sensor  but also by the quality of color rendering which looks perfect to my eye (the same is applied  for Canon TSE17).
   Also I was surprised by quality of autofocus using  Metabone III adaptor for a7R, I thought that I would have to use manual focus get best focusing results.

  Pictures taken using Sony Zeiss 24-70 looks as if they were  taken by cheap  average camera system, and colors look a somewhat "dirty" - as if there is something not very clean and transparent  between the camera and the object  so results are not very pleasant  to the eye.
  By looking at DXOMark test results I knew that they are not in the same league as Sony Zeiss 55 F1.8  or Canon EF24-70F/2.8M2 and perceptual resolution is low  (15mpx)  but  I expected better actual performance than I saw in my tests.  Even DXO Optic Pro  9  lens correction does not help much to bring image quality close to that of Canon EF24-70F/2.8M2. It makes image a bit better but still far below of IQ when using Canon EF24-70F/2.8 M2.
I was expecting a bit more from  Sony Zeiss 24-70  at least in color rendering quality.
This lens doesn't  not match a7R sensor performance  at all, despite the fact that Sony claimed just the opposite.
Even not up very much to the a7 sensor resolution
So Sony Zeiss 24-70mm-F4-ZA-OSS  usability is limited to general walk-around average point and shoot requirements when image quality is not an issue and person just need light camera for easy carry around.

But  Canon EF24-70F/2.8M2 on a7R is almost perfect combination when image quality is main concern.
a7R could be considered as high quality digital back for high quality Canon lenses including EF24-70F/2.8M2  and TSE 17 and TSE 24. The only one perfect native lens for a7R is Sony Zeiss 55 1.8 which is extremely good and allow to use all a7R resolution capacity.

Lenses / Canon EF24-70mm f/2.8 M2 vs Sony Zeiss 24-70 on Sony a7R body
« on: April 03, 2014, 12:20:12 PM »
  I was always  interested to know what is the resolution power limit of Canon  EF24-70mm f/2.8 M2  combined with the high resolution body and  how this compares to  similar lense type from different vendors.
On Canon 1DX this is just perfect piece of glass.

  Few days back I received Matabone III adaptor which gave me ability to mount Canon lenses on Sony a7R body.
With that I was finally able to test Canon  EF24-70mm f/2.8 M2  on 36mpx   Sony a7R body.
As result there  is also comparison of image quality  between Canon  EF24-70mm f/2.8 M2    and  Sony Zeiss 24-70 f/4 OSS.

There are two 100% crops at 24mm focal lens and two 100% crops at 70mm  focal lens.
All shots  are done  hand held  using camera autofocus.
Focus speed of Canon  EF24-70mm f/2.8 M2 with Matabone III is very slow - few seconds of hunting and searching for focus peak.
Sony Zeiss 24-70 f/4 OSS  focuses almost instantly.

 RAW files  from  Sony a7R were process using Phase One  Capture One with default settings, no adjustements at all

Test results demonstrate that Canon  EF24-70mm f/2.8 M2 is much superior to Sony Zeiss 24-70 f/4 OSS in resolution and color reproduction and overall image quality .  Especially this is noticable at 70mm focal length .
From test pictures it is obvious that even on 36mpx   Sony a7R body  Canon  EF24-70mm f/2.8 M2 still does not reach it's limit in resolution power.  This combination is perfect one when focus speed is not important.
On the other end  Sony a7R with  Sony Zeiss 24-70 f/4 OSS  is a fairly good combination as general purpose  walk-around point and shoot camera.

I also tested Canon TSE 17  on a7R and image quality , color rendering and resulution is also of top possible quality. 
It seems that Canon TSE 17 the same as Canon  EF24-70mm f/2.8 M2 still does not reach it's resolution power limit on a7R
Canon TSE 17  on Sony  a7R  looks as  perfect  combination for Architecture and Landscape photograpy.

Couple of more samples.
All shots are processed in Phase One Capture One with default setting, only shot with flowers has highlights slider set to 5 % to show more texture on white flowers
I tried a7R with Lightroom 5.3, DXOOptics Pro 9.1 and Capture One and the last gives more pleasant results for a7R files compared to DXO and Light room.
DXO also very good - with default settings output looks better then LR5.3
May be this is personal perception  but to my eye C1 do much better rendering for a7R raw files than LR5.3
Now waiting Metabone adapter to  test  it with Canon TSE 17 glass

Just got my a7R,  very pleased with the convenient controls, very fast AF - expected that it would slower
Did some tests with ZEISS 55 1.8  and  below are some samples - one full image- small size, the other 100% crop  with 100% Jpeg quality, all handheld
Very good addition as walk around camera  to 1Dx

EOS Bodies / Re: Canon's Medium Format
« on: February 14, 2014, 05:46:34 AM »
When they can give me a full frame MF sensor (6x4.5) for about the price of a 1DX I'll start saving for one. :)  (yeah, fat chance, I know)
There is an option there - new Pentax 645D 2014 which will become available probably by mid 2014. Pricewise should be not big difference from 1DX system

Sony is pushing limits with it's  new MF 50mpx CMOS  sensor - vey high IQ at ISO6400:
The IQ250's new Sony-built sensor offers options for medium-format shooters, including high-sensitivity performance up to ISO 6,400; exposures as short at 1/10,000 of a second and as long as one hour; and a dynamic range spanning 14 f-stops for a better ability to capture details in both shadows and highlights. It doesn't take advantage of CMOS sensors' superior ability to shoot video, but that's no surprise or even shortcoming given that Phase One sells machines designed solely to capturing the best still photos possible.

Found  interesting info on  Sony 7R image quality vs. 5Dm3, Nikon D800E and Pentax 645D with 100% comparison crops at different ISOs at imagine -resource:
 Very interesting to see comparison of Canon 5D M3 with Sony a7R  at ISO 3200  both  low contrast high details shorts and for high contrast ones.

Both images are full size files.

I used the very cool MultiExposure method (as I learned here on CR). It's ONE raw file on both images, shadowpushed to +100 in LR, and +40-something with shadows in the tone curve. I was out to really push the shadows as a test, not to create a HDR-image, and this is why the whites are a bit over here and there. I specifically chose a VERY high contrast scene I didn't expect any camera to perform any good at all. And the light is nowhere near as crazy with the things I normally shoot, or care about if the subject looks good.

Those who say the 1d X is dissapointing need to figure out how to use it...
It is pleasure for me  to see that Multiexposure method which I described last year here for 1Dx   is being used providing best possible IQ out of 1Dx.  When 1Dx is also used with extremly sharp 24-70 2.8L M2 or TS-E 17 4L  image IQ is just amazing - it is hard to believe that it is possible- I always amazed with the quality. There is one issue though for Phase One C1 and DXO Pro  white balance for ME files  - I opened the case with both and DXO already reasearched it  and found the problem and will fix it in future releases. Phase One  is still working on that. But root cause is the same - they did not took into account that color balance is already applied by canon  in ME output RAW file and appliying that for second time in SW which result in strong violet color cast for both DXO and C1.  As for now Canon   DPP provides best white balance for ME files- better then Lightroom.
LR4 works fine but Canon DPP  is even better for color balance - no corrections at all are required.

Third Party Manufacturers / Re: Canon may be expensive but...
« on: February 04, 2013, 02:03:39 AM »
@neuroanatomist & @TheSuede :

I think you are both correct but there are two aspects here.
 Hopefully modern sensors are designed in a way to prevent photocell saturation in normal conditions and at base ISO saturation point of photocell (or point just below) should match upper level of input voltage range of correspondent  ADC. This is required to obtain maximum possible DR from the sensor at base ISO.

 With lower light input (so less input photons) higher digital ISO should increase analog circuit gain so less photocell output should be amplified to the same upper input voltage of ADC.
This also explain why sensor DR is reducing 3db with ISO going up one step (for properly designed up do date modern sensors - e.g. from Sony you see that starting from base ISO).
 So for HTP at ISO higher than base ISO negative exposure compensation could be done just by reducing analog circuit gain.
But at base ISO this might not work - we still would need to reduce number of photons by reducing exposure time or using ND filters to prevent photocell saturation.
 Unfortunately there is no freely available information for sensor cell full path gain distribution (from photocell up to ADC) to see actual sensor performance in this respect (for different sensors). This would be interesting to see - actually this is one of the most important parts of the system design.

Third Party Manufacturers / Re: Canon may be expensive but...
« on: February 03, 2013, 01:25:04 PM »
Was reading this thread and could not help but putting some comments.
Let's look at the root of the discussed HTP issue 
What is the blown highlights means for the sensor? 
Really blown highlights ??
This means that photodiode of the photocell got saturated and any increase in number of captured photons cannot increase current via this photodiode .
Anybody is going to argue about that ?
Then what could be the remedy for this?
Answer is simple - reduce the number of photons.
How this could be done?
Use EC to  -1  and then later in processing  change gamma in tone curve to raise mid-tones and shadows  to the level which would be produced if camera  was used with EC=0.
This could be done manually or camera could do that automatically using HTP mode but reporting that all was done with EC=0 , actually cheating camera user.
This all simple physics - anyone could see response curve of the photodiode and understand what it is all about.
It does not matter how you name what is the happening but essence of the process does not change with this.
If photodiode is saturated no further on chip electrical post processing could recover highlights - they already blown.Full stop here.
This is ABC of electical engineering.

Third Party Manufacturers / Re: Hand on SONY RX 1.............AMAZING
« on: December 21, 2012, 04:51:21 AM »
Here is Michael Reichmann RX1 review on much respected -very interesting:


this may not be the most objective site but it's worth a deeper look though (is there anybody objective out there?):
Thanks, very interesting article.
Author is right telling that "It is REVOLUTIONARY instead of EVOLUTIONARY".
This is what I was meaning in my post  telling that they are putting milestone in digital cameras evolution process. Somthing drastically different and starting point of new path in cameras evolution. Step up from what we have now on the market

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