Wide and Sharp, Batis vs Canon
There are superb lenses and incredible lenses in the market. The first type is always a model with so many pros to be able to keep the flaw hided and the lens became a standard.
The Canon EF 16/35 f4 L is one of this lenses; sharp from f4, corrected until the borders, nice microcontrast and color rendering , great stars and almost cheap. I tested it on 20, 30 or 50 mpx on Canon bodies and on 42mpx of Sony bodies and the results were always perfect without other problems than flares on strong backlights or the weight if you start complains about that on reflex gear.
I sold that glass but I wasn’t 100% sure about, that action was related to my conversion to the Mirrorless world and because I tested the Zeiss Batis 18 2.8. Finding inside the german (japanese) glass so much quality from the 2.8, a superb microcontrast and an incredible light weight was the main factor even losing the stars of the former glass and having to fight with one big problem for a landscape photographer: the field curvature.
I had many times to use both of them in the same moment later during my job but just last week was possibile to make a good test on a rich of details landscape. I consider the two glasses made for almost different purposes, one for landscape and one for reportage/starry night and the test was clear.
So with my Sony a7r3 I putted in sequence the Canon and the Batis at f5.6 and f10. Why?
On 42 megapixels without AA filter, f5.6 is the golden spot for a glass to have maximum amount of details in the whole frame and to keep away the main amount of diffraction; in the same time, f10 is a good aperture for a landscape photographer to keep most of the frame in focus to avoid the need of a stack and to have a nice star from the sun or the streetlights.
Main image is at 5.6 :
Both at 5.6
We can easily see the highest sharpness and micro contrast in both center and corner from the Batis images; not an incredible difference but visible; Canon lens is just a stop further from its maximum aperture so is optimized for deeper apertures sadly inside the effect of a major diffraction. I had to focus on the BORDER of the images on the Batis to avoid any possible problem from the field curvature.
here at f10
As we can see now the Canon lens is on his golden spot, better rendition in the whole frame and the magic touch of the super micro contrast of the Batis is gone. Diffraction is already high at f10 and the AA filter effect is visible with lost of many of the finest details seen in the last test.
Some of that could be also related to the higher ISO used on this second test (100 vs 400) , but for sure here appears obvious the different destinations of both great glasses.
Below is the main destination of the Batis, the reportage photography. On this picture shot at 2.8 we can see the incredible reproduction without any loss of sharpness on the corner for the conic perspective at maximum aperture.
The flaws of the Batis? Sensibility on diffraction and field curvature.
There is another sample of diffraction in action on Batis: f 4.5 vs f9, quite impressive, this lens is optimized for wider apertures for sure. The f9 pictures seems to come from a sensor with Aliasing filter.
I also wrote about the filed curvature of the Zeiss glass; yes is not heavy like other lenses I own (hello Canon 24-70 2.8ii!) but is here when we want our landscape shot sharp from edge to edge.
On this samples on the left I shot focusing in AF in the center and on the right manual focusing on the edge of the frame, in both the center is sharp but the edge is quite different!
Thanks for this reading!