I chose a situation where I could use a reasonably high ISO -- in this case I settled on 1600, although I did the test in a range from 800-6400. The real problem with comparing two unequal sensor sizes is that the final images are not the same size, but what I wanted to find out was how the images would compare if they were the same size. This meant I had to either up-res the Fuji image to 36mp or down-res the A7r to 16mp. I chose to go the high route and make both images 36mp.
My preferred method to up-res an image is to do it in Adobe Bridge where I can utilize the full 16-bit RAW file information in the process. Comparing the two images showed what I expected, namely, that the image from the A7r would naturally show a higher resolution than the one from the X-E2. What surprised me was that it did not show a significant difference in noise between the two at the 1600 ISO. So my next thought was: Could I perform a gentle massage to the Fuji X-E2 file that would bring it closer to the image quality of the A7r file? For this I went back to Bridge.
|This is the naturally room lit scene setup for the test images. It was photographed with both cameras set to ISO 1600 and f/5.6. You can download the Sony A7r file and the up-res 36mp version of the Fuji X-E2 file with the links below.|
In Bridge on the X-E2 RAW file I gently adjusted the sharpening and detail tools until I had a reasonable facsimile to the A7r image. Adding the sharpness, small as it was, increased the contrast and started to lose some of the highlight detail. To fix this I lowered both the highlights and the contrast until it looked right.
|For the X-E2 RAW image I set the Resize to fit option to 36.2MP in the "Workflow Options" area of Adobe Bridge. This produced an up-ressed version of the Fuji 16mp file to equal the size of the A7r file.|
|Sharpening sliders in Adobe Bridge were set to 55 for Amount, and 50 for Detail. Luminance Noise set to 16, and Luminance Detail at 50.|
Both cameras were on a tripod. For the Fuji I used a standard, screw-in cable release. For the Sony I used a 10 second delay timer because the camera only accepts a proprietary release that I didn't have.
The purpose of this exercise for me was to see if I could approach a 36mp, full frame image quality of a superb camera sensor like that in the Sony A7r using a Fuji X camera and applying some moderate post-processing techniques. I actually surprised myself with the results. I did not go into this experiment expecting to come as close as I did to equaling out the two images.
There is an old adage that says: "It isn't the camera; it's the photographer." What I think this experiment illustrates is that proper camera technique and good use of post-processing are as important as the camera itself in producing top notch results.
I also found the X-E2 a far easier camera to use. The Sony A7r has an annoying two-step process for changing the focus point, something that Fuji thankfully corrected with firmware awhile ago. The Fuji menus in general are easier to navigate, and niceties like the good old standard screw-in cable release socket make a photographers job that much easier.
The point of this exercise was not to see if one camera was better than another. Instead, I wanted to see if the Fuji X-E2 with its handicap of smaller sensor and lower megapixels could approach the level of a top full frame model. You can judge the results for yourself by downloading the images above. As far as I am concerned, the Fuji X-E2 came through like a champ.