Call me crazy.

But its done. Incoming, is the Fujifilm GF 500mm ƒ 5.6 OIS lens (which i bought second hand): Which is the longest native lens for the mediumformat GFX camera.

My thinking is simple: A super telephoto lens without compromise - nor Fringer adapter. The latter which acts a bit weird mechanically in my case - albeit when it works - the digital implementation / communication with the camera is indeed excellent.

I want one super telephoto lens for the GFX system i can trust on - in situations, where things are slightly faster, or the light levels are not optimal - and still performing well.

Pentax 645 FA telephoto lenses

are indeed good - no doubt. As long things are relatively bright, and nothing unexpected shows up demanding more snappier actions. Not that the Fuji 500mm lens is a speed demon - it is not. But it is a native lens - there by still performing better than any adapted lens, down to the finest details.

That being said, i do love the Pentax 645 lenses. I take my tame with them, work very carefully, so that the images are sharp, well in focus - so that neither stabilization nor focus are being thrown off. At home i often apply gentle sharpness (e.g. via Photoshop Noise AI) to my images - in order to further increase the impression of clean sharpness and clarity: It does lift the old Pentax 645 FA lenses to a very high level !

I don't really need to do that with native Fujifilm GF lenses. We all know who use that system, that the Fujinon lenses are the best for that 102 MP sensor.

So, the 500mm lens will be my reference lens. Like the Olympus 300mm (600mm) lens is my reference telephoto lens for the Olympus system; as it operates on the highest possible optical level you can get out from a MicroFourThirds sensor.

The man with the motor bike above

That photo is actually not truly entirely focus. His face in the original is slightly fuzzy. This isn't visible in a smaller photo like here in my Diary - which goes from 102 MP to around 4 MP here.

The situation was faster than it looks like. He suddenly showed up in the middle of the road in Old Town Stockholm - then stood still 2-3 seconds, turning quickly around and was gone in less than a second.

So, I had to act quick. Unsure if the focus will "nail" his face.

When too fast...

For that sort of thing, the combination of Pentax 645 FA 400mm lens, Fringer adapter and GFX camera - while the street was in reality in the shadows of morning light - often giving me relatively slow shutter speeds (in comparison to the focal length of 400mm) - and the AF can sometimes miss ever so slightly focus sometimes, if I am too fast. (A fullframe camera wouldn't have had any problems). But this set-up (GFX + Pentax 645 400mm AF lens) isn't your average joe setup.

While some blur doesn't matter for a PHOTO when e.g. the overall impression of it is interesting, good or in other ways make a nice composition - as many famous images made in humanity were anything but sharp.

That however is no excuse to be sloppy, either.

Know your tools

And yeah, there i am quite bit picky; I like things to be sharp when i aim at sharp images. Still - with all the Pentax 645 FA lenses, its in an experimental phase; to test the limits of what I can and can't do (when I use those lenses on a Fujifilm GFX camera).

Along the road, once i know how and when the AF works reliable - and where its weaknesses are - I can adjust accordingly. That's the whole purpose right now.

I think the Fuji 500mm will do a better job in scenarios where shutter speeds fall due to lower light levels. I believe that the AF focus will still more stable compared to the older Pentax 645 FA lenses, and more precise when situations are of faster character (but not too fast, then even the Fuji will likely quit).

It isn't a sports camera / lens after all ;-)

Great lens with some weaknesses

Oh by the way; The Pentax 645 FA 400/5.6 ED fringes quite a lot (at wide open apertures) ! You have that green/red effect around sharp details. If you have thinner details (beams, houses, antennas) set against the sky, you get blue-purple halos. This usually diminishes once you stop down. Sharpness is very good, but you need to be very stable and calm, push the shutter button lightly several times, in order to make sure that everything is exactly in focus. Then take a deep breath - and things turn out sharp *LOL*

Even worse is the Pentax 645 FA 200mm ƒ4 (IF) lens when used at wide open aperture; it gives a LOT of purple in high contrast situation.

Now... the Fujifilm GF 500/5.6 OIS on the other hand - does not do fringing or chromatic aberrations.