I finally took series of comparison shots with Hologon 8/16mm CG and Distagon 2.8/15 ZE. As Dr Nasse published and elaborated by measurements (with courtesy of Horst Wittmann), Hologon has very huge resolution drops at the edge of full frame. With APS-C there wasn't such a problem, especially without this severity (at Sony NEX-7). Telecentric Distagon lens hasn't any problem to image to Sony A7's sensor with very pleasant outcome.
Carl Zeiss Hologon 8/16 CG
Carl Zeiss Distagon 2.8/15 ZE at f/2.8
Crop 200% of photo shows bands (with Carl Zeiss Hologon 8/16 CG)
One more interesting observation are horizontal strong bands (lines) in the extreme regions of images, which was taken with Hologon lens. They are symmetrically distributed in extreme upper and extreme lower part of photo, horizontally they are best visible at 1/3 and 2/3 of photo's length but they are available at full width of image. They forms regular, repeated pattern, which upper and lower group of lines are mirrored to each other. Even magenta colour of upper lines are complemented with green colour of lower bands. Upper bands, around text label, are better visible, because they are projected at quite bright, plain (solid color) background. If I moved the lens radially, those lines didn't change position (rotation). So this effect isn't connected with any not radial properties of lens (like scratches on lens's surfaces).
Do You have any idea if those bands are physic devoted (like some of optical effect, eg. diffraction) or it could be some post-production (like eg. electronic or firmware related problem) error?
I even thought about some sensor malfunction but as far as I tested it, those bands are not visible with any SLR lenses, even those with very short front focal lengths.
Thanks for any advices or ideas.
best regards, WZ.