This is part 13 in a series of posts on a prototype of the Kolari Vision thin-stack sensor modification for the Sony a7II. The series starts here.
The Zeiss 35mm f/2 Biogon-ZM, being a symmetric design, doesn’t do too well in the corners on the a7II. How does the Kolari thin stack on the a7II compare with the Leica M240 with that lens attached to each? Both cameras have 24 MP. Neither camera has an AA filter. The Leica has special angled micro lenses, and camera firmware that reads a 6 bit code off the lens and performs optimization based on the lens model number. I’ve manually coded the lens as a Leica 35mm f/2 Summicron-M ASPH.
The scene at f/8 with both cameras. I focused on the center with live view with both cameras. With the Leica M240, that’s the only option. Maybe I’m stacking the deck against the a7II, but I figured it would be cheating to use the put-the-focus-point-anywhere feature of the Sony to focus in the corner.
Both images were developed in Lightroom with the default settings, except that the white balance was set to daylight. Lens profiles were turned off. Lightroom does some lens-dependent sharpening that is not defeatable, however. Lr knows what lens it thinks is on the Leica, and it has no idea what lens is on the a7II because the adapter doesn’t provide it with that information. Let’s look at the center at 3:1 enlargement to make sure that Lr is not stacking the deck in favor of one of the cameras.
Except for the white balance difference, they look the same to me.
Now let’s look at the lower left corner at all the whole apertures that the lens can use. I brightened the corners to compensate for lens falloff.
The Kolari has more smearing.
The Leica is pretty good by now. The Kolari has a ways to go.
The Kolari still lags. The CA is not going away.
Still some smearing with the Kolari.
The Kolari is almost there.
Leica by a nose.
Diffraction takes over and sharpness is a dead heat.