Hi, I am looking at a used Fuji GX617 with the 105mm lens. I am looking for info from the group here if the center filter is required for the 105 lens? Also, if you are a GX617 user/owner, if you have any thoughts about the camera and your experience, I would love to know them.
Not a GX, but I shoot 617s with a Fujinon SWD 90mm.
On Velvia 50, there's a little bit of vignetting, but really nothing that's offensive, I can live without a centre filter most of the time.
That said, I do have a centre filter for it, a Schneider IV that works perfectly.
So if you've got a 105mm, the effect is only going to be less noticeable than at 90mm. I'd say try without it, then get one later if you really don't like the vignetting.