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And here I figured Steve Hendrix or Doug Peterson would be the first to point that out!yeah, sort of strange.
Of course, if you upgrade to the IQ4 150, almost all of that color cast will disappear
And here I figured Steve Hendrix or Doug Peterson would be the first to point that out!
Yuck. :thumbdown:Ok, this has been bugging me forever and I finally have the guts to ask: I always thought symmetry was kind of important in physics. What is it about a pixel that is not symmetric?
Dave
35xl / IQ3100 no movements:
I know it looks bad, but they usually clean up pretty well in C1. Here is an example that is a pretty good test:Yuck. :thumbdown:
Could be. It would have to be temperature effects that target photons at crazy Schneider obtuse angles, not straight-on Rodenstock photons. Hmm. I wonder how temperature affects micro lenses or sensor well walls.My guess is higher temperature of some components near the sensor.
M
Not sure how you set this up, but I'm guessing we're looking at CFA crosstalk. CFA's aren't symmetric.Ok, this has been bugging me forever and I finally have the guts to ask: I always thought symmetry was kind of important in physics. What is it about a pixel that is not symmetric?
Dave
35xl / IQ3100 no movements:
Thanks, Jim. Do you mean the array itself being rggb isn’t symetric, or the way it is interpreted isn’t symetric or both? Why is it more uniform in the long dimension vs the short dimension?Not sure how you set this up, but I'm guessing we're looking at CFA crosstalk. CFA's aren't symmetric.
Jim
I mean the array itself is not symmetric. The way the colors look on a flat field image is going to depend on which filters spill over on which pixels, and on the white balance of the illuminant. Maybe to some degree on the demosaicing algorithm. Certainly a lot on the lens design and aperture. A classic CFA crosstalk case is the "Italian Flag" and that sure isn't radially symmetric.Thanks, Jim. Do you mean the array itself being rggb isn’t symetric, or the way it is interpreted isn’t symetric or both? Why is it more uniform in the long dimension vs the short dimension?
Dave
Definitely not the lens that is asymmetric. Since I can rotate the lens every 90 degrees, I tried that...Is the LCC a lens cast correction, correcting anomalies in the lens, or a sensor cast correction, correcting anomalies in the sensor? It would seem to be the latter, since it is not needed (or needed less) with the IQ4.
I get that the four squares of the bayer array are not symmetric. Certainly it is easier for red and blue to spill into green than it is for red to spill into blue because they only touch at one point (and vice versa). What I don't get is if I fly down from my mini-helicopter and land on a sensor, I cannot tell which way is North, South, East or West unless I know precisely which row and column I am on. No matter which direction I face, I can easily get into a position where there is a red filter behind and to my left, a blue filter in front to my right and two greens in the opposite corners. All I have to do is walk around one or two pixels. That's why it hurts my head to see the global difference in color cast across the short dimension.I mean the array itself is not symmetric. The way the colors look on a flat field image is going to depend on which filters spill over on which pixels, and on the white balance of the illuminant. Maybe to some degree on the demosaicing algorithm. Certainly a lot on the lens design and aperture. A classic CFA crosstalk case is the "Italian Flag" and that sure isn't radially symmetric.
Jim
Alpa STC. I’ve done some reasonably critical testing of each corner by both rotating the lens and by using Jim Kasson’s corner-recompose approach. I am quite sure the lens plane is parallel with the sensor. The 35xl doesn’t have room for the tilt adapter so that isn’t in the mix either.What camera is this on?
I have a similar issue when I shot lcc's but I thought it was because of slight deviation in parallelism.
I missed the part about lens dependency. Never mind.Could be. It would have to be temperature effects that target photons at crazy Schneider obtuse angles, not straight-on Rodenstock photons. Hmm. I wonder how temperature affects micro lenses or sensor well walls.
Dave in the Weeds