Does Sony's "clear zoom" work with non-Sony lenses? Or with the LA-EA2 + A-mount?

Started Mar 29, 2014 | Questions thread
captura Forum Pro • Posts: 26,129
Re: Does Sony's "clear zoom" work with non-Sony lenses? Or with the LA-EA2 + A-mount?

Digital Nigel wrote:

captura wrote:

Digital Nigel wrote:

GaryW wrote:

Digital Nigel wrote:

captura wrote:

Because they're no the same thing.
I refer you to this brief explanation from Sony:

"Below are the definitions of optical zoom, clear image digital zoom and Precision Digital zoom. In short for the best image quality Clear Image digital zoom has a database of patterns it can refer back to and create new pixels for a better quality image than Precision Digital zoom which is basically just crops in.

Optical zoom: true zoom, by using optical zoom quality remains the same and the full resolution of the camera can be used on the zoomed image.

Clear Image Digital Zoom: the processor compares patterns found in adjacent pixels and creates new pixels to match selected patterns, resulting in more realistic, higher quality images

And how, exactly is that different to bicubic resampling ("With bicubic resampling, first the coordinate of each pixel in the output map is determined; then the values of 16 surrounding pixels of the input map are used to calculate an interpolated value for each pixel in the output map”)?

Bicubic applies a formula, while CIZ pattern matches. You can read the difference in the blurbs above. We aren't going to find out details as it's proprietary. Perhaps it uses even more pixels to establish a pattern. Who knows?

OK, I did another test, this time using remote controls as some people seem to think that's a better test of an extended zoom than shooting distant buildings. Again, both shots were on a tripod, OSS turned off, properly focused, same camera settings, low ISO, and these are 100% centre crops. The RAW has again been upsampled, using bicubic sharper in DxO:

So, I have two questions:

  1. Do you see any significant differences between these images that suggests that CIZ has a secret, superior, pattern-based algorithm compared to boring old bicubic, that allows it to extract extra details or show smoother images?
  2. And if you do, which do you prefer?

I delved, for more clarification:

"The 'Clear Image Zoom' function relies on Sony's rather clumsily-named 'By Pixel Super Resolution' algorithms to upsample images to a higher resolution than that at which they were captured. In essence, it's a form of digital zoom, interpolating data from that on hand to fill in the blanks. According to Sony, Clear Image Zoom offers better results than competing digital zoom techniques, though, because it uses pattern matching techniques to improve the quality of the guessed data. Clear Image Zoom functions in steps of 0.1x, up to a maximum of 2x zoom beyond the actual focal length of the image, and Sony claims that the image quality even at 2x Clear Image Zoom will be "nearly equivalent" to that shot with an optical zoom at the same equivalent focal length."


"Does zooming in CIZ (in Jpeg ExtraFine) bring better results than traditional cropping in RAW?"
"All CIZ is doing is cropping the shot. There is no advantage in doing it in camera vs cropping later. You are reducing the mp as you crop (I think its 14mp on 50mm) so either way you are going to get the same result. Doing in camera gives you a JPEG while doing it separately gives you the ability to at least do some post of the file. You can also access the other virtual focal lengths from 35mm to anything...
The only advantage, maybe, of using CIZ in jpeg is that you can 'see' the FOV of what you are taking a photo of. All else is just a crop."

There's some interesting comments in that thread.

Do you have a preference between the two remote control crops I posted above?

Not at this time. Soon spring will come and I will dig out my camera gear, etc. With the new information, do you have any more insights or preferences?

 captura's gear list:captura's gear list
Sony Alpha NEX-7 Canon EOS Rebel SL1 Sony a7 Olympus OM-D E-M10 Canon EF 85mm f/1.8 USM +3 more
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