I just made the transition from a 50R to a 100S. I was not unhappy with the 50R, but after a lot of shooting with the 100S am glad I made the change. I am keeping the 50R as a backup. Here are some thoughts:
Don't get a 100S for the increased resolution as your main reason. There are twice as many pixels, but not double the resolution. I didn't have any issues with the resolution of the 50R. However, I will say that I now realize that much of the appearance of sharpness of the 50R relative to the 100S is the microlenses, perhaps creating stronger local contrast and the appearance of sharpness. There's more actual detail in the 100S images if that matters, but also lower local contrast in RAW files straight out of the camera.
Do get a 100S if the sum of the following benefits is worth it for you:
- Like Jim said, the aliasing is dramatically less. There's a lot of aliasing in 50R files. It didn't bother me a lot before I got the 100S because I didn't have a baseline. Now that I've seen what the same subject looks like with the 100S and the 50R, I see the aliasing much more.
- Are you using camera movements? The BSI sensor in the 100S makes a huge difference. Most of the lenses I use on my digital view camera setup were fine on the 50R, but my Mamiya N 43mm f/4.5 L had slight colour shifts even unshifted, and noticeable colour shifts at 5mm of shift. Like the aliasing, I didn't take note of it as much with the 50R before I got the 100S. Now that I've seen how the lens does on the 100S, I realize that there was enough colour shift on the 50R to affect the image.
- You would like to use your camera off tripod or monopod. The IBIS in the 100S is transformative if you shoot hand held with a 50R. I could not reliably use my 50R without a tripod. Some people say they can. I was never happy. You can easily shoot handheld with the 100S.
- The grip on the 100S makes it much easier and more comfortable to hold than a 50R. It's not even close. Add-on grips on the 50R are a poor substitute. Side note: the 50R with its diminutive grip was the only GFX I could use on my Toyo VX23D, but my F-Universalis can take the big grips so the plus of the 50R grip became a minus for me.
- The screen flipping up in portrait mode on the 100S is a major improvement for how I use the camera. I use that function all the time. It's a huge benefit to me.
- I don't miss the dials on the 50R as much as I thought I would. I have set up the buttons and wheels in a way that makes perfect sense to me. I also use the submonitor a lot; it's extremely handy. After a few outings, I am now completely fluid with the 100S. I don't even think about where things are.
Finally, shutter shock was never a problem with the 50R, but it's something I have to deal with using a 100S. The problem is the same on a 50S II according to a colleague of mine who has one. When I'm using the 100S on my Arca-Swiss F-Universalis, I must use ES (electronic shutter). Electronic front curtain shutter (EF) degrades image quality with every lens I use when I'm shooting under 1/100th of a second; I'm not sure where the safe zone is at slower speeds, but conservatively let's say 1 second. Mechanical shutter is unusable on the 100S mounted to my F-Universalis. Hand held with IBIS, EF is fine with the lenses I use (GF 35-70 and various adapted). EF on a tripod with my GF 35-70 and with my adapted lenses in a simple adapter seems OK (but ES is still better). Jim has posted test results for longer native lenses that suggest EF is still degrading image quality. Again, I never had to think about the shutter with the 50R; I put it in EF and never moved it from that setting.
I don't know if you use adapted lenses. Some people insist that only native GF lenses are up to the task on the 100S or 100. As a blanket statement, I think that's nonsense. But your results may vary.
Good luck with your decision. I thought long and hard about mine, and have no regrets.
