The Sinaron CEF 5.5/90 has an image circle of 140 giving you lateral shift capability of 20mm and vertical shift of 25mm on a 48x36mm chip - this is a non HR lens but plenty sharp. The Sinaron 5.6/135 CEF gives you an image circle of 150 but lateral shift of only 20mm and vertical of 22MM
the new(ish) 4.5/40 HR gives you an image circle of 90mm I dont have the exact shift specs for this.
These indicate that for longer lenses you are really better off with using MF glass on a 645 body - especially given the lesser ( if any) disparity in edge to edge performance.
same can't be said of wides in MF land compared to Rodenstock /Schneider wides - but then again MF wides give you leaf shutters and syncing flexibility at shutter speeds > than 1/500th - accuracy on copal shutter at limits is problematic anyway.
it really is a no brainer to go for an artec or similar for anything longer than 35mm in my book - and then if you have an artec you may as well use the extreme wides from rodenstock anyway as well...
this is suspect is why Alpa are to introduce this nifty new TC with inbuilt lateral movement - small package hand shootable and on tripod shiftable..
of course you already get the same thing with a 12SWA and Max - except the body is larger.
The new 12TC is appealing to me
because of its small size - really nifty little travel kit - but certainly no substitute for a camera with inbulit focussing screen and loupe not to mention tilt and shfits..
I dont buy the Alpa argument that you cant build a sliding system which is accurate enough - I am more a buyer of the argument that
no one builds any system accurate to perfection - thats why optimal apertures are advertised @ f8-11 anyway ..but thats another story.
put these on tripod and shoot tethered if you want perfect focus.
sorry I got a bit off topic.
but yeah I am a buyer of the new TC when it comes out - sign me up Paul -