Wide lens test request on GFX or Actus

[dnercesian]

Just to be clear, I am actually going to be using a dual shift adapter on my Leica SL and I have been looking at wide angle options with the ability to control the aperture as well as get a little bit of movement in the 19-24mm range. Due to the relative specificity of the requirements, it is difficult to fins all these lenses on one place to test out, and ordering/returning lenses until I find the right one is not really practical considering the availability of some of them. So thats why I am making this request here, hoping that the collective, so to speak, may be able to offer some samples or data that may shed some light (pun intended).

My first choices, which I am already feeling may not work but want to make sure:

Leica R 19mm
Leica R 21mm
Leica R 24mm
Leica R 21-35mm

Some other ideas:

Rokinon Cine 20mm (Cine lenses have aperture rings)
Rokinon Cine 24mm (Cine lenses have aperture rings)
Nikon 17-35mm D
Nikon 20mm D
Nikon 24mm D
Zeiss 18mm ZF.2
Zeiss 21mm ZF.2
Zeiss 18mm ZE
Voigtlander 20mm (Nikon Mount)
Sigma 20mm Art (to use with Nikon G lever type aperture adapter)
Sigma 24mm Art (to use with Nikon G lever type aperture adapter)
Tokina 16-28mm (to use with Nikon G lever type aperture adapter)
Nikon 14-24mm (to use with Nikon G lever type aperture adapter)

Or any other lenses you might possibly think of...

Of course I know I can easily cover the image circle and have a mechanical aperture with certain medium format lenses, but the widest I believe I can go is 35mm.

 

[chrismuc]

- Olympus 24 PC
- Schneider, Pentax, Nikon 28 PC
these allow shift, have sufficient image circle and have manual aperture

- Zeiss CY 21
has just very slightly larger image circle than required for 36x24, so a tiny bit of shift would be possible

 

[Paul2660]

Of all my nikkor glass, really only the 14-24 was good on the GFX, from about 18mm and out. No corner vignetting and very little corner softness from F8 to F11. On my lens with the Fotodiox adapter, bottom corners were very sharp, top was a bit smeared.

Same lens on a 35mm sensor doesn't show this.

Of course I am just guess on the actual F8 and F11, as there is really no way to know what the actual aperture is when used on the Fotodiox, but you can at least control it.

Paul Caldwell

 

[Audii-Dudii]

I don't have a GFX, but based on my experience using Sigma Art lenses with movements on a Cambo Actus / A7R combo, I can add the following:

- A Sigma Art 20/f1.4 won't work, because the permanently attached lens hood restricts the image circle such that minimal movements are possible even with a 36x24 sensor (without it, though, who knows? I may try again with another copy and remove the hood, but this was a borrowed lens, so that wasn't possible this time around.)

- A Sigma Art 24/f1.4 (sans lens hood) has a fairly large image circle and from f8 on, my sample, at least, should come very, very close to covering a 44x33 sensor (although Jim Kasson's testing of his sample showed hard vignetting in the corners, so maybe not or else there is some variation between copies.) However, the sharpness does fall off considerably toward the edges of the image circle (again, with my copy; not sure about others), such that I have learned not to use the last ~5 mm or so unless that area is all shadow and no detail (which does sometimes occur, actually, as I photograph urban scenes mostly at night.)

- A Sigma Art 24-35/f2 (sans lens hood) has a large image circle, as do many other zoom lenses. Toward the 35mm end -- say, from 33-35mm -- and from f8 onward, it should come very close to covering a 44x33 sensor, but no way at focal lengths shorter than that. (It works great at all focal lengths with a 36x24 sensor, though, although there are only a few mm of movements available at 24-28mm and it exhibits noticeably more barrel distortion at the short end of its range than does the 24mm prime.)

- A Contax N 17-28/f2.8 zoom has an image circle roughly similar in size to the Sigma 24-35/f2 with the rear baffle removed. Unfortunately, its corners smear badly at 17-19mm with the A7R's sensor and cover glass combo (much, much less than with the Kolari thin-filter mod, btw, but that caused other issues with my A7R, so it's not a solution) which may or may not also occur with the GFX. Unfortumately, I am not aware of any adapter that will mount it to a GFX -- or a Cambo Actus, for that matter -- so it will be necessary to make one yourself or have one made, although I can't imagine why anyone other than myself would ever do so to use it on a GFX. From 21mm on, though, it does have some appeal when used with a Cambo Actus / A7R combo (well, assuming your a life-long fan of Zeiss glass, as I am.)

I have ordered a Sigma Art 35/f1.4, but the one I received last week was for the wrong mount, so I had to send it back and haven't tested it yet. That said, I have read reports that its image circle is roughly the same size as 24/1.4's, hence my interest in it, but we shall see what we shall see, eh?