Marc,
I may add some points to the Con section...
Cons:
- The weight is enormous. 1.5 kg is nearly twice as much as most other TS lenses. And yes - for THAT weight you need a tripod mount! With other TS lenses - weight was never a reason for wanting a tripod mount.
Yes the weight is quite high. I don't care though, as it is such fun, at least for me to work with. However I try to limit the overall carried weight. So in the the end I don't think my backpack is heavier than the typical landscape bag. But yes weight is an argument. The advantage of the tripod mount, however is not only that it takes the weight off the lens. It fixes the lens and lets you only rotate the camera, which again frees you of all parallax errors. Actually I am using also the Canon 24TS and 17TS with a Zork tripod mount.
- Using shift on the Hartblei is counter-intuitive for me (which may be a question of taste).
I like it, but yes thats a taste question.
- Shift only goes in one direction, and it is only 10mm.
Canon 45 has 11mm shift. 1mm more. You can get more shift however if you use the Mirex Canon -E-Mount adapter with it. (The Hartblei comes in Sony A-Mount, Canon or Nikon Mount). 15mm shouldn't be a problem. However extreme shifts will also cause corner distortion.
- Changing the direction of shift (from up to down or to left/right/diagonal) means rotating lens and camera in the lens collar and then rotate camera versus lens. While you do that you loose the levelling of the camera (there are no markings or even detents on the tripod collar).
True, but with leveling devices built in the camera it is just one turn, as only one axis has to be adjusted. Takes less than a second. By the way, if you get proficient in the use of the lens, you know before you level the lens if you need upshift or downshift, and you will do it right from the first time
- If you tilt then it has a side effect: the image center will be shifted. With a full tilt you need most of the shift capabilities of the lens just to compensate for that. That is not the case with the Canons.
I have to disagree but as I understand it, this is right for all TS lenses. If you move tilt in one direction, you will to counter that movement with shift, otherwise your composition will change. In landscape photography you typically are interested to get the whole image sharp. By not diving to much into the theoretical aspects of TS photography, if we take an extrem case with a hinge line distance of 70 cm with a 40mm lens, you will have to use about 4.5 degrees of tilt. 10mm shift will always be enough to counter that amount. The Canon has 1 mm more shift. IMHO a more theoretical value.
Having said all that, in the end it comes down to personal preferences, like always. And looking at your website, I can see you that you know very well about TS photography.
Cheers
Jan