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Lenses / Re: Canon TS-E 17mm f/4L Tilt-Shift Lens - your thoughts?
« on: April 10, 2014, 03:50:31 PM »
Canon TS-E 17  is perfect optical system in all respects.
Once I bought it I stopped using my older 16-35 II 
It is easy to use, even handheld.
I used it initially with 1Dx but  1DX resolution was not enough ,so  I bough Sony a7R specially to use with TS-E 17.
Together they give amost MF IQ.
Here is example of TS-E 17 on a7R with Metabone MIII adapter.
First image - is almost all frame - just a little bit of cropping.
The other two are 100% crops from different image area.

Sony/Zeiss don't seem to have figured out how to make a first rate zoom for their A7s yet.  If you compared the Sony/Zeiss 55mm 1.8 you would have seen a significant difference too (the 35mm 2.8 as well, probably).  But you don't need to attach Canon lens as new/expensive as the Canon 24-70II - you can get fantastic images from many much less expensive Canon lenses on the A7r, even such bargains as the 40mm pancake and 85mm 1.8 - if nothing else, the A7r shows just how good many Canon lenses are!
Fully agree  that "Sony/Zeiss don't seem to have figured out how to make a first rate zoom for their A7s yet"
Sony 24-70 proved even worse than I saw in my initial tests.
Did some walk around with this lens on a7R, looked at the images  and found that at short focal length images get blurry at the sides of the frame  though more or less OK closer to the center of the frame.
I am very disappointed with the  Sony 24-70 - seems that this lens more or less could be good for  NEX7 and similar but not a good fit at all  for a7R.
But Sony/Zeiss 55mm 1.8  is just perfect on a7R .

 As for using other cheaper than  EF24-70 F/2.8 M2 Canon lenses on a7R I agree with you  that  excellent results could be achieved with cheaper Canon lenses.  For many people with a7R as second to Canon body  this could be good solution. I just do not have them.  Some of the Canon lenses though  not expensive but are the best in their class
For me my EF24-70 F/2.8 M2  is the mostly commonly lens that was used on my 1DX  recently and now it is also perfect fit for a7R

It's the old dpi/ppi thing again
Yes , agree there are a number of confusions about that

 In fact relation between  printer output image  pixel resolution  (PPI_print) and  printer Dots Per Inch (DPI) resolution could be expressed in general  (not going deep into details) as follows:

PPI_print = Function (DPP, DPI, Paper_Quality)
DPP (Required Dots Per Pixel)  = Printer_Driver_Mapping_Function(Required_Pixel_quality, Number_of_inks_in_Printer, Avaiability_of_Variable_Droplet Technology, etc. )

  Modern printers (e.g. Epson Stylus Pro 3880  or 4900 and others ) can provide final print resolution above 720 pixel per inch (required output PPI  is set in print settings  dialog box in imaging editing program).
  Here is discussion of printer PPI ( not to be confused with DPI)  - printed images final resolution  using HP 932c
"I could see significant reduction in the finest details in the 300 ppi print vs. the three higher resolution prints, and a slight reduction in the 567 ppi vs. 720."

   So the argument  that using Canon EF24-70 F/2.8M2 on a7R   does not give any benefit for printing compared to Canon EF24-70 F/2.8M2 on Canon 1Dx is not correct.
   Though difference would be almost not noticeable when downscaling a7R file to 1Dx size (details are lost in downscaling)   but  when full-res a7R image would be printed  on  A4 or A3  then  difference will be visible especially on A3 print which could not be considered large - if you want to put picture on the wall in your room the best minimum size would be A2
. Also higher quality higher res image gives more flexibility to cropping.

Here are A4 and A3 printouts resolutions at fine 720dpi and superfine 1440dpi
  So from above it is clear that in fact even most Buyer sensor MF cameras can not over perform standard quality 720dpi A4 printing resolution.
I dont think you understand what those 720dpi & 1440dpi means
Are you really sure of that ?  :)

DPI means exactly what it means - print spatial resolution  - dots per inch)

  "Dots per inch (DPI, or dpi)[1] is a measure of spatial printing or video dot density, in particular the number of individual dots that can be placed in a line within the span of 1 inch (2.54 cm)"

So what I said above is 100% true for BW prints, for color prints it is a bit different depending on  printer model, number of different ink cartridges in printer resulting in required number of dots to reproduce full color in single image pixel.
So for color print pixel to dot mapping is a bit different - more printer dots required per color pixel
But actual printer resolution for fine printing is 2880x1440dpi , so you can redo calculations above for this DPI density and see equivalent BW  resolution for A4 and A3 prints and estimate color resolution

In general these details do not  change much the main the point  - modern color printers are outperforming most of the digital cameras in print resolution even on A4 prints, let alone A3 or A2 prints.
So you can see difference between high MP and average MP image printouts  even on A4 format, but this difference will be almost unnoticeable if high MP image downscaled to average MP image resolution . There is no lossless downscaling - if you downscale image in resolution you will loose fine image details.

The A7r user is gonna want to print some big pictures to gain an advantage.

  This is most common confusion and misunderstanding repeated all over different forums from person to person and this resulted that this is taken as granted by majority of the of people who are arguing about value of high MP sensors

In fact this is totally wrong.

Downscaling high MP image to the lowest resolution camera image in comparison and viewing results will never demonstrate how high MP image will look on real print. Viewing this results on the PC monitor is the same.
This is actually what many people are complaining about DXO sensors comparisons when they are normalizing  images to 8mb.  At these days it would be better to normalize images to 24mpx which is de facto common reference point now.

Now coming  to high MP image printing.

Here are A4 and A3 printouts resolutions at fine 720dpi and superfine 1440dpi

A4  8.3 x 11.7 inches
Pixel size  for 720 dpi   = 11.7x720  x8.3 x720    equal to  8424 x 5976 =  50.34 MP
Pixel size  for 1440 dpi   = 11.7x1440  x8.3 x1440  equal to  16848 x11952 = 201.367 MP

A3 11.7 x 16.5 inches
Pixel size  for 720 dpi   = 11.7x720  x 16.5 x720 equal to  8424 x 11880  = 100.077 MP
Pixel size  for 1440 dpi   = 11.7x1440  x 16.5 x1440  equal to  16848 x 23760 =400.3 MP

  So from above it is clear that in fact even most Buyer sensor MF cameras can not over perform standard quality 720dpi A4 printing resolution. On printout every dot is compete pixel . For Buyer sensor effective resolution is about 60-80%  of actual pixel count. So only Phase One IQ180  image could match in resolution to  fine quality 720 dpi A4 printing  resolution  and far below of fine quality 1440 dpi A4 print  let alone A3 printouts.

So difference on IQ and resolution between 24mp and 36mp will be clearly seen even on A4 printout.
Even on small screens difference in resolution is very noticeable.
This is why people want to have retina displays on their smartphones  and now new trend is 4K screens on the smartphones , let alone TV set.

 As for big prints at very high resolution  - they give you feeling of the real reality. From far distance you see overall image, when you get closer and closer you see more and more  details - the same as in real life. On big landscape print  from 400mps image you get very close and you would be able see even bee on the flower and flower petals texture and fur on the bee belly.  And you will fill  this as it is real reality

How about posting the A7 with EF 24-70 sized the same as the 1Dx.
OK, here is comparison  of A7R with EF 24-70 sized the same as the 1Dx with Canon EF24-70F/2.8 M2 on 1Dx
a7r with Canon EF24-70F/2.8 M2 looks a bit better even if  downscaled to 1Dx size

Fair enough.
How about posting the A7 with EF 24-70 sized the same as the 1Dx.
I already posted  a7R with Canon EF24-70F/2.8 M2  which shows how much it is superior compared to Sony 24-70 on a7R
It could be  easily downscaled  to the 1DX size in any photo editing program to see the difference.
Result of normalizing image to lower resolution is obvious - perceptually it will be the same or bit better  IQ only with less resolution.
So it would be a bit  better that 1Dx with Canon EF24-70F/2.8 M2

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  http://www.dxomark.com/Lenses/Sony/Sony-FE-Carl-Zeiss-Vario-Tessar-T-STAR-24-70mm-F4-ZA-OSS 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

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