There are some drawbacks though. Uncannily enough, they’re the same as with the Canon EF 28mm ƒ/1.8 USM: slight vignette with a hard vignette at infinity focus. At ƒ/8, it isn’t very prevalent as you’ll see in the samples, easily corrected with a 5:4 crop that retains 48MP. However, as the aperture gets smaller, the vignette hardens, as you can see at ƒ/32, but still works at a 5:4 crop ratio. The lens works fine with a 3:2 crop at full sensor width and in 35mm crop mode, so you can choose what works best for you. Weirdly, the lens changes focus as you move in and out of playback mode on the GFX...
Widening out to an approximate 22mm in 35mm format terms, the Canon EF 28mm ƒ/1.8 USM does show some hard vignetting that is never fully resolved. It’s very, very slight and occurs at ƒ/4 and smaller at infinity focus. Vignetting is prevalent fully open, mostly disappearing by ƒ/4 at close focus distances. If the vignetting is a problem for you, the EF 28mm ƒ/2.8 IS might be a better bet but isn’t on Canon’s list of preferred lenses for the 5DSR, so it may or may not resolve well on a 50MP sensor.
After spending a few weeks with the Sigma 50mm ƒ/1.4 Art, I've come to realize maybe Sigma lenses aren't the solution for me. At least the 50mm has a very short focus throw, making manual focus a tedious process, even with focus aids like focus peaking and focus zoom. Autofocus is just too unreliable and slow to depend on for all occasions, making manual focus capability a priority.
One thing I quickly discovered is the intrusion of the lens hood when adapting 35mm lenses onto the medium format GFX. Since the 50mm Sigma casts an image circle closer to 40mm, it's going to pick up more of what's on the periphery of the field of view; in this case it's the lens hood.... Continue Reading →
If you'd like to contribute your findings, please include lens specifics (brand, focal length, maximum aperture, lens version, firmware version, and if it's weather sealed or stabilized), adapter used, and camera used. Full sensor sample shots without the lens hood (JPEG, 2000x1500 pixel minimum) needs to be of a white or gray background at the widest aperture at both minimum and infinity focus, repeating this at ƒ/8 and at minimum aperture, be it ƒ/22 or ƒ/32.
This is the first in a series of posts on individual lenses adapted to the Fujifilm GFX 50S with the TechArt Pro EF-GFX adapter. Fujifilm GFX 50S, firmware v3.30 (latest) TechArt Pro EF-GFX, firmware v1.01 (latest) Sigma 50mm ƒ/1.4 Art, firmware v2.02 (latest) Summary: Full compatibility: Autofocus, EXIF OK. This lens shows a correctable vignette throughout the aperture range but is heavily affected by focus breathing. As the aperture shrinks, focus toward infinity causes the vignette to become harder and more pronounced. Despite this, it is easily cropped and corrected while maintaining 45mp or more.
I'm obviously not a professional photographer. Now, some may take that to mean an enthusiast has no need for a "professional level" camera, but that is entirely untrue, even on a general level. What the GFX offers is resolution. 50.1 megapixels of it. What I offer my camera is a crippled body, unable to get the most from any camera body. I can not hike as far, climb as high or go as long as an average photographer. I also cannot drive due to the medications I need to operate from day to day. Because of that, the GFX's resolution returns to me an ability lost by my inability to drive: repeatability.
With the recent resurgence in film, I've begun to lust after shooting film again. Maybe I'm romanticizing the days when film was the only option but I Long for it just the same. The main driving factor behind my recent purchase of a Fujifilm GFX-50S was a desire to slow down my photographic process; medium format digital requires me to be more deliberate in my photography with its slow focusing, slow shooting and high resolution demanding an extremely stable platform for the best results. Something else that has the same demands? Film.
The biggest news was the purchase of a Fujifilm GFX 50S, GF 45mm ƒ/2.8 lens and TechArt autofocus EF-GFX lens adapter. It arrived just before Xmas and I was able to use it for parts of both latter shoots. I also gave it a couple of runs, one from Kerry Park that was foiled by fog, another from Rizal Bridge that wasn't. The increase in resolution is shocking. Shots taken from the bridge could be cropped down to 8mp and were still crystal clear. Also shocking: the size of the uncompressed RAW files at ~140MB each.