2.) The MTF curves - even if they are computer generated should take
into consideration these effects otherwise the MTF graph would be
completely rubbish
canon's pretty honest, if you look at the 17-40 or the 16-35, or even the 24 L II or original, or the 14 .. they pretty well mirror what users have experienced in the field as far as performance. Good, bad or ugly, they are not far off.
BUT if the published MTF curves turn out to be true theses lenses
might probably outperform all existing wide angle lenses.
without getting too excited with no real reviews, if the MTF's match real world performance, then they could be very well the sharpest prime / shift lenses out there - especially sub 28mm.
the 17mm TS-E could very well, on the basis of a prime lens, be the sharpest 21mm or under lens out there - both of them may very well give the vaunted 21mm distagon a run for it's money. again if the results match real world. Especially since the distagon's only show down to 40lp/mm versus canon's 60lp/mm (or 30 lines/mm)
I hate to get too excited over modelled MTF's - but those as far as UWA are very very very good and have potential to be game changing - as much as the 14-24 was for nikon.
as resolutions of FF sensors increase, the need and the value of tilting a lens to achieve critical sharpness over an extended DOF will become more and more important. tilting the focal plane is the only method outside of focus stacking to achieve critical sharpness at the pixel level across an extended DOF.
In other words, it's more possible to extract critical sharpness over a wide DOF using a 17mm TS-E then it will ever be out of a 14-24 nikkor at 17mm.
the tactical benefit of that cannot be ignored - on a 21Mp canon or a 24Mp D3x / A900, after F/8 you start to get into the effects of blurr and some resolution loss because of diffraction effect. as the sensor density increases, critical sharpness at large magnifications will highlight this more - tilting the focal plane allows you to still use the lens at say f/5.6 to f/8 and have the appearance of f/16 to f/22 in DOF on a regular UWA. comparing the results of the two side by side would be readily apparent.
So it all depends on Canons ability to get the glass production under
control. Here comes also the long term experience of Canon on the
plus side. Furthermore the forms to do this must be done properly and
this costs pre investment - other companies (in financially bad
shape) might not be in a position to do such an investment at all.
which goes hand in hand with the costs associated with the lens, the testing of these lenses before shipping adds to the costs to meet or on basis of quality inspection come close to the MTF's on a per unit basis.
if you look at the other premier shift lenses out there, none of them that are in the elite category go for less than 2 to 3K .. you truely do get what you pay for - and out of all of them, the canon's have the widest image diameter - almost a full 10mm wider than their closest nikkor counterpart.
Grinding the lenses is not an option because this process would be
even more expensive.
I don't think canon totally utilizes molded elements, and some are still ground, but they are checked against a master lens during the fabrication.
So nikon got it all wrong - they've kept the small mount and they put
away the aperture ring so they have no advantage of the old mounting
system except the compatibility to older lenses that only sometimes
reach the actual designs in terms of image quality.
hard to say on that one, the F mount has one benefit that the canon mount doesn't have - which is a longer register distance, that makes it easier for light to hit the corners of a FF sensor without being on a significant angle. the angle is less on a F mount than it is on an EF mount - if all things such as exit size remain equal.
