That is a long name for a lens! All those letters mean something though, the first part is pretty easy to figure out and the last part, well the designations that mean the most are the OIS for optical stabilization and the WR for weather resistant.
I took delivery of this lens back in January. I don't really use telephotos much. I really only use one for an occasional bicycle or motorsport race and around the woods and my yard for wildlife and birds. I have had several from Nikon and a long one from Sigma but they were pretty heavy and cumbersome. I eventually grew tired of them, keeping only the Nikon 80-400mm F4.5-5.6 VRII. That lens though just never seemed to work where I wanted it to. It suffered by being sort of soft at long distances. The contrast and color nor the build quality got me very excited. It was the size of my 70-200 2.8 VR a lens I use a lot, and weighed similarly. Good points. That still didn't save it.
So, I decided to sell my remaining long glass and try the soon to be coming Fuji 100-400mm after seeing how well Fuji did with their other XF system lenses. I don't do a whole lot of lens testing and have no optical test bench. Just some tired old eyes. I find lens results are subjective anyway but I personally like to see how a lens handles a scene for contrast, color and sharpness. Both up close and far away. You may be surprised to know many telephotos are not at their best when shooting far distances of 100 yards or more. Sort of ironic.
I had only really played around with the big Fuji, never really pushing it. I sort of wondered about the sharpness though as some of my photos seemed a bit fuzzy. I suspected user error, figuring my technique sucked. As it turned out, I think it did and does! Another prompt for this test was a post on a forum I happened across where a user stated he thought his copy of the 100-400 was soft. He claimed to be a veteran telephoto shooter. I checked other online reviews that gushed over the lens. I found no other negative comments. Did Fuji build product with extreme sample variations? I decided to test my big Fuji once and for all and settle my fears. I used my X-Pro2 both handheld and mounted on a Feisol carbon fiber tripod, a very sturdy rig I have used before. I shot at only 400mm for this, using apertures from 5.6 (wide open) to 8. I tried various shutter speeds and used auto ISO to keep the exposures consistent. Very similar settings to how I use it when I'm working.
I shot at close and far distances topping out around 225-250 yds. I used "targets" I have used before with my past telephotos so I could have a point of reference. The photos here are samples of my results set. I used LR to process them using a variety of Fuji camera profiles of Astia, Classic Chrome, Provia and Acros Y. I used LR to apply standard sharpening and to make Basic adjustments. I set the white and black points mostly and just went from there. Nothing heavy handed.
I tried tripod shots with OIS on and off and found no real difference that I could see. This will warrant more work. The OIS though does work well when handholding it. I don't have them in this post but I do have handheld results with shutter speeds of 1/60 sec and the pics are sharp. I think the big Fuji works very well at distance too. Blows the Nikon 80-400mm zoom away. Its not even close. I tend to like the f/8 versus the f/5.6 shots but I could live with both. I also think it works pretty well up close. Fuji did a good job with this lens, its not perfect but the price in dollars and weight for perfect isn't in my budget. Its far better than anything I have tried. With that said, what really remains to be tested is the auto focus. How quick it locks to a target and holds it and how it tracks it as it moves. This is one area where my Nikons shine. I just never had the lens to go with it. I have not had a chance to try the AF testing yet lacking good subject material. I will be shooting Trans Iowa in a few weeks, its a long endurance race and while I don't need a 100-400mm zoom to cover it, I will bring it along to see how that AF tracking and locking fares.
As I said, my technique needs work. I will put the time in and see if I can improve my handholding skills. I would certainly never second guess another photographer, but I can't help but think the poster on that forum needs to work on technique some more. At the very least he needs to lock the lens and camera down on a good sturdy tripod and ballhead and test near and far. I love the weight and size of this lens. Its a bit pricey but built very well. It is on the slow side but again the cost and weight would increase a lot and my cameras can handle higher ISO settings so I don't need a 2.8 version. I do wonder though if a constant f/4 version would be that much bigger.....cost that much more......in the mean time bring on the X-T2 since I do feel the big lens handles better with that body and grip combo. Seriously good job on the 100-400 Fuji. Keep 'em coming!