TakenWild
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I'd agree with you the Pentax 645 75mm is the best shifted lens in their lineup. The 35mm is also not bad. The 55mm is a very sharp lens, but has really bad field curvature, which makes it unsuitable for infinity landscapes.
I do have experience with Pentax 67 lenses on Sony A7R2. I have the latest 67 55mm f4 and the latest 75mm f4.5.
rdeloe wrote:
I can't do a side-by-side anymore of the Canon FD 35mm T/S, but I did own that lens and use it a lot. It's a remarkable performer for a lens of that vintage. Yes, the Canon T/S Mark 2 lenses blow it out of the water! However, the Canon FD did a fine job on a Sony A7 all things considered.
I sold it eventually for two reasons. First, I wanted a wider range of T/S options. Second, unlike the Canon T/S Mark II lenses, you don't get tilt independent from shift. The choices are tilt with shift, or tilt with rise/fall -- and you have to physically disassemble and reassemble the lens in the orientation you want. This is hard on the screws and not something you'd want to do with any regularity.
I switched to a dual Mirex setup to get what I want. The first Mirex adapter is EOS to NEX, and the second is Pentax 645 to EOS. I used EOS as the common interface because it has by far the widest throat. Together, this combination allows for tilt independent from shift/rise/fall. It's as close to a view camera-like setup as you can get with adapters I suspect. Next step would be an actual view camera rig (see post above) or a Cambo Actus setup.
The lenses I use in my setup are SMC Pentax-A 645s. I use the 35/3.5, 55/2.8, 75/2.8 and 150/3.5. I also have the 45-85/4.5 zoom. It's really good a the wide end (as good as the primes, and certainty better at 45mm than the SMC Pentax-A 45mm lens, which is a bit of a dud). At 85mm the zoom is a bit soft.
Unshifted I'm really happy with the image quality of these 645 lenses. I realize they're not up to the standards of the best modern glass, but in my testing and personal opinion they're still excellent (with some variability among lenses). I tend to shoot at smaller apertures (usually f/8 and f/11) and I shoot for black and white. In that context, I've had no concerns.
As for shifted, I was perfectly happy shifting all of thse until yesterday! Forum member TakenWild had posted elsewhere that image quality was poor at large shifts. That was news to me and I was skeptical at first... but then I did my own testing yesterday and today. Sadly, it's true that as you get closer to the edge of the image circle, there's a definite IQ fall-off. Rats!
* In my testing, at 5mm rise in portrait orientation (shifting up) all of the P645 lenses I use are totally fine.
* At 10mm of rise in portrait my 35, 55 and 150 lenses are showing a loss of resolution and an increase in purple fringing (which doesn't exist at 0mm shift) at the top of the image. The 75 is still fine.
* At 15mm of rise in portrait, the 35, 55 and 150 are looking a bit grim, while the 75mm is still holding its own.
In all cases, all of the problems experienced are much worse wide open than at f/11, and are largely limited to the top of the portrait-oriented shots (because that's the part that's closest to the edge of the image circle).
So... what do you do? It comes back to what you need. I've shifted the 35mm Pentax-A lens 17mm (using rise on the two adapters), and I've been happy with the result. Here's an example: http://www.robdeloephotography.com/Image-Galleries/Guelph/i-fQtjh38/A Yes, it's true that the spire at the top of the church tower is showing some distortion from this large shift. It's hard to see in this tiny web print, but my target was a 17x25" print, and you can see it there if you come up close. However, I needed that shift to get this image, so I'm happy with the tradeoff. Your standards may be different -- so it's difficult to give advice once we get to this point. I'd say that if you need absolutely no image quality loss during 15mm shifts, you won't be happy going this route (Mirex adapters and P645 lenses).
Like marktomaras, I'm looking forward to hearing anyone's experiences with the Pentax 67 lenses. Those have a much bigger image circle, which would keep you farther away from the edge during a large shift. The tradeoff is weight, and the widest non-fish eye Pentax 67 is 45mm -- not wide enough if what you need is 35mm. That's yet another trade-off......Show more →
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