I tested my LifePixel-modified (720 nm option) Fujifilm GFX 50R with the Leica 280 mm f/4 Apo-Telyt R lens and a 950 nm lowpass filter. I added a +100 contrast boost in Lightroom.
Poor coverage, no hotspots.
Still has corner vignetting. No hotspots.
A little bit of corner vignetting. No hotspots.
No corner vignetting. No hotspots.
I guess the question is going to be whether to use the lens at f/8 and deal with the slight vignetting, or to use it at f/11 and suffer the diffraction, which is about twice as bad at 950 nm as it is in visible light. I’m thinking that f/8 is the plan.