Zeiss Loxia vs Zeiss ZM 35mm f/2 Biogon on Sony A7R
Pre-Order Zeiss Loxia lenses at B&H Photo.
See the Zeiss Loxia announcement.
Zeiss has provided some test images shot on the Sony A7R with the new Loxia 35mm f/2 Biogon, along with images made with the existing Zeiss ZM 35mm f/2 Biogon (M mount).
Has the proven Biogon design of the Loxia 35/2 Biogon been tweaked, and also optimized for mirrorless?
The test images show that the Loxia 35/2 Biogon is a step up from the ZM 35/2 Biogon, long considered a very fine lens, but which was never designed to take sensor cover glass of digital into account, and the ray angle damage to image quality (extreme astigmatism as well as exacerbating color fringing, stopping well down is needed to counteract).
In short, the Zeiss Loxia lenses look to be the right choice for the Sony A7s/A7/A7R shooter looking for classic Zeiss all-metal build quality in a manual focus lens. Ergonomics of manual focusing also look to be much more hand friendly (wide barrel).
Crop is from an image taken at ~ 1:40 reproduction ratio. Both images are in focus.
UPDATE: I’ve examined the images carefully at all apertures. I am not satisfied of a precise focus match between the two, which puts the ZM 35/2 Biogon at a disadvantage. But examining all areas of the images, it’s clear that the ZM lens is suffering at the periphery from ray angle effects. So the crop below is not as bad as it looks for the ZM lens, but it is definitely not performing as well as the Loxia lens. This particular crop is at edge and field curvature means that its focus is not optimal for either lens, even as center is sharp.
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