I got the longer Mamiya extension tube No 2 (82 mm) which lets me focus closer with the Mamiya APO Sekor Z 210mm ƒ4.5 lens. And I must say... even as i really focus a lot closer - the lens is holding up. Whether at wide open aperture ƒ4.5 or stopped down; sharpness is very, very good.

Barely any chromatic aberrations to speak of, no matter which aperture you use.

So yes: The Mamiya RZ67 APO versions are really playing on a top level. Now the 210mm lens is the "shortest" lens among the RZ67 APO lenses: 250mm, 350mm and 500mm whopper. Except for the 210mm, none of the other APO lenses are of my interest - because they are simply too long for what I most often do, when adapting it to the Fujifilm GFX 50s II camera.

the whole image @ ƒ4.5 [Fujifilm GFX 50s II]

Mamiya APO Sekor Z 210mm ƒ4.5 (+No 2 extension tube) @ ƒ4.5 [Fujifilm GFX 50s II]

Mamiya APO Sekor Z 210mm ƒ4.5 (+No 2 extension tube) @ ƒ11 [Fujifilm GFX 50s II]

I could of course go even closer...

by combining the Mamiya No1 + No2 extension tubes together. But boy, that thing would be absurdly large / long... Not sure if that is something i have any use for, really. The No 2 extension tube alone does a great job. It now gives me a better close-up distance with the APO 210mm lens instead of the No 1 extension tube, I mean).

I am really so glad with my home-made / self assembled, super stable Mamiya RZ67-GFX rail-based setup. It really pays off in the most stable way !!!

Fujifilm GFX mounted with Mamiya APO 210 lens + No 2 extension tube + compendium shade

A Novoflex Balpro T/S

would never be able to cope with such dimensions nor the total weight of everything together. I am pretty happy that I didn't walk that path, and "waste" another 1500 € or more on it.

It also seems pretty clear to me, that i can use the APO 210mm lens for portraits at wide open aperture ƒ4.5. It is more than plenty sharp and doesn't show any chromatic aberration or other optical strangeness. I still have to test that with Sal - but we haven't gotten there yet. For unknown reasons we never had a time together to work together when we both were off. Something came in between. Last weekend, I was suddenly ill (albeit i continued to work throughout the time), so my energy focused entirely on getting though work, but nothing more then that.

With the new Godox DP800 III V studio flash however, I had an additional reason, to set the photo studio in order again. Albeit i need to set up special curtains, which keep out daylight - now that it has gotten much brighter.

I do find the APO 210mm intriguing

As its optical performance is fantastic - and compared to the other longer Mamiya APO lenses, the 210mm is more flexible.

Curiously the APO 210 it the most affordable among all RZ67 APO lenses, with a cost lower than most modern lenses. Often around 300-400 € (The prices have has gotten up slightly). I think i paid something like 300 € when i bought it in 2017.

Notice that the cheapest eBay offerings often show issues like hazy lens elements, mold or/and element separation. Despite the designation of "nearly mint" - which i think is ridiculous label. Sharpen up Japanese sellers - what kind of utter BS label is that to put on a hazy lens ?! It certainly has nothing to do with mint conditions - at all.