FF sensors expensive to make? Think twice

[bobn2]

It could well be that Nikon
is using a lithography based lens layer, which therefore shows
artifacts and canon is using some other technique (or even used it's
50mm square stepper to make the original) and so its microlenses
don't display stitching, even though the underlying chip is stitched.

Is there an example image around where the stitching artifacts are
obvious? Before this thread I hadn't heard of anyone complaining
about this problem with any digital camera.

There are two, I think. One is the chipworks article ( http://www.chipworks.com/blogs.aspx?blogmonth=3&blogyear=2008&blogid=86 ) where they show this image:



There are clearly stitching artifacts here - my claim is that the ones you see are in the microlens layer. It is probable that there are also artifacts on the silicon, but you can't see them because of the microlenses.

The second is a sensor analysis of the D3 here: http://www.brisk.org.uk/photog/d3greensat.html

where they show this image obtained from the D3 sensor, after extensive pushing, showing similar artifacts.



In neither case is what is shown incompatible with my theory. In the first case, clearly when looking at specular reflection off the chip surface what you will see is irregularity in the top layer. In the second, patterns like this are more likely to be caused by misalignment of the microlenses than anything else (after all, even if slightly misaligned, the sensels themselves should be the same either side of a stitch).
--
Bob