As per yesterday’s post, the Fujifilm GFX + 120mm f/4 has some kind of unstable focus problem, which I believe is an electronic glitch (my working theory). It appears to be “safe” to shoot the 120/4 for the initial (single) shot, after that all my aperture series show damage from this glitch. Definitely unsafe to shoot more than one frame in succession (without refocusing) with the 120/4. That is with a 2nd brand-new 120/4 and brand-new GFX; this is no “bad sample” problem but a serious bug.
Accordingly, I am taking the GFX on my trip to the Eastern Sierra along with the 32-64mm f/4 zoom, the 63mm f/2.8, and the 120mm f/4. I am going to be careful in that I will refocus for each of the frames so that I can obtain full image quality (which of course makes stitching all but a non-starter, but oh well).
That is to say: my working theory is that focusing before every shot will bypass the glitch. I don’t yet know if the glitch affects the other two lenses, but I don’t want to come back with many gigabytes of garbaged aperture series.
It’s terribly difficult in the field to shoot a system that is unstable when I don’t know the root cause, but the GFX sensor is a worthy sensor, and I think I can make things work out to show the best the system has to offer from each of these lenses, even if I cannot reliably do my usual aperture series approach. So I’ll just refocus each shot and I should be able to get optimal results for each individual shot.
Impressive: the GFX can focus on a single bright star for night shots, at least with the 63mm f/2.8. Update 2: not so fast: the focus is no good, and I ended up with a blurry 8 minute exposure. Gah!
I think I’ll do a fair amount of work at Cerro Gordo, which has lots of interesting stuff for all these lenses (the road is open and free of snow as of today). If by chance a reader wants to meet me for a photo tour, I will be available on April 2/3/4/5 or thereabouts for Cerro Gordo and the Eastern Sierra, White Mountains, and northern Death Valley. One day or more. We can do whatever you prefer: photography in general, stitching, panos, 'post, whatever.
Below, one of the old mining building at Cerro Gordo (NOT a Fujifilm GFX shot)