If you have lightroom on the Color adjustments sliders ( HSL / COLOR / B & W Tab) Turn down the purple and magenta on HUE / Saturation/ Luminance until you get the result you want.I find this works pretty good in most shots and is much easier to navigate than Cornerfix.
-Jim
Lee Saxon wrote:
I don't understand it. The sensors Sony sells to Nikon are so good...
Nikon doesn't have an aps-c or FF camera that can use M mount lenses and their short registration distances, and, if they did, they'd be battling the same issues. The Sony 16mp sensor in the NEX-5R and NEX-6 does a better job with color shift.
Douglas (et al) ... could you expand on that a bit. I get some shift with my SLR/C to varying degrees with my alt, wide and tilt glass. It would help if I better understood the optics of what is creating this issue, so I could better determine how to approach preventing it.
It's been talked about quite a bit in the NEX thread(s), cornerfix thread, and maybe even in a Zeiss thread somewhere where a recent article from Zeiss on the subject was brought up.
I don't have links to the pertinent threads available.
Long story short, it comes down to registration distance, configuration of the lens optics, and the sensor size, sensor optics, and/or incident angle of the light rays. Trial and error is the best way to know when a given combination of the above will work or not.
In terms of NEX, all 16mp sensors AFTER the 5 handle the issue much better, the 24mp sensor only makes it worse. The problem mostly arises with focal lengths under 35mm.
Otherwise its caused by sensor being bit more 3D then flat and light goes under wrong angles on corners, causing colors to shift.
Only happens when you use lens designed for rangefinders and only some (mostly wide-angles). Regular adapted dSLR lens shouldnt do that. It happens on wide-angle zoom from Sony too.
Corner (angle) color shift, is caused by microlens (reside right over pixel on most of digital sensor -but not all ), those are far from the center may make negative effects on the lightbeam.Bayer or Foveon sensors are suffered but in the last one this is more critical, where the fotons need to go deeper as it has 3 layers.Usually this phenomenon is met with wide angle ,where the angle of view over 60 degrees, but I myself suffered from this also with supertele 400mm, when did a conversion Canon 400mm f/5.6 L to Sigma SA mount.
CornerFix is convenient for batch file processing.It helps but not for all occasions, fortunately for landscapes, when I reduce the iris this phenomenon becomes subtle and the pics are acceptable.
So, if I understand correctly, the broader incident angles are not completely redirected (AI=AR @ refraction / reflection) by the microlens, allowing scattering of energy to occur to nearby subpixels. Such that for that energy that isn't fully captured by green subpixels, there will be residual/reflected/scattered energy being captured by neighboring red & blue (thus purple) subpixels, or conversely if the red/blue subpixels aren't fully capturing, the nearby green (thus green) subpixels will capture some scattered energy.
So, the wider the angle of incidence, the greater the difference between refracted vs. reflected ... and the wider the aperture, the more varied the AI Similarly with tilt functions, the varied AI's aren't fully refracted, allowing for more reflection to neighboring subpixels. Thus, the more stopped down the aperture, some reduction in the angles of incidence occurs ... mitigating some of the scattering.
Doesn't necessarily have to do with the microlenses alone, but also the filter infront of the sensor. Anyone with a Leica M8 will know what the UV/IR filter you put on the lens does with the corner color.
I mentioned about IR cut filter already, but it's correctable easily- microlens design is the same as sensor design and we'll do nothing to it, that only suffer from it.How about tilted microlens or angle-correctable sensor?
@RustyBug: thanks for the link, I read alot : how does it work?, but not this before, now I know more about MICROLENS SHIFT to correct green/magenta edges.
