Hi Don,
You will probably not ever see a 50MP in "full frame" but I guess anything is possible.
IQ150, on tech camera, my thoughts.
For me a tech camera is mainly used for movements to create a short pano, so I am looking to shift on Acra 15mm or 20mm (with Acra rotated). Tilt is also important for DOF of foreground subjects. I used the following lenses:
28mm Rodenstock HR Pink Band
35mm Schneider
40mm Rodenstock HR-W
60mm Schneider
90mm Rodenstock HR Pink Band
120mm Schneider non macro
All on Arca rm3di
Difference in subject distance, between cropped sensor and "full Frame" like IQ260 for me was around 12 physical steps or around 10 feet. So to get the same framing, I had to move back 10 to 12 feet with the IQ150.
On the 28mm, the smaller IC of 70mm still comes into play pretty quickly, and you start to see a hard vignette by 8mm or so of shift horizontal. Rise and Fall, you might get 10mm. Center shows a good bit of pink/magenta and any shift past 3mm really the shifted portion is very red, which quite a bit of loss in overall saturation. LCC does a good job in cleaning up the color cast, but on the 28mm some still shows on edges of shifts and sometimes on even center frame. When you view the image on camera LCD, the shifted portions can start to look like B&W due to the hard loss in overall saturation. There is enough loss that your first thought is that it can't be recovered, however C1 pulls enough back that you have to really hunt to see the fall off. BTW this is with the CF on the 28mm, with it off the effects are much worse IMO.
35mm Schneider allowed shift to around 10mm, with quite a bit of harsh magenta on the edges. LCC cleans up nicely, and CF was always used.
40mm Rodenstock, was a dream, easily could go to 20mm of shift, there was quite a bit of red shift and saturation loss by 12mm to 20mm, but again the LCC seeminly recovers most if not all.
60mm Schneider, has the least amount of magenta color on center and again was easily shifted to 20mm. The harsh red edges of shifted files was not as bad as on the 40mm, and I felt that over all it was the best lens on the IQ150. when I could use it. I also had the CF on the 60mm.
90mm Rodenstock and 120mm Schneider are wonderful, can be shifted up to 25mm, albeit my 90 being an HR pink band did start to show some smearing past 20mm. LCC again works very well.
One issue that is not mentioned much, is the vertical banding, that is very visible on a lighter subject, say blue sky or white/grey subject. This is not like microlens ripple which is very straight and uniformed, instead the banding was much more wavy. I pointed this out to my dealer as soon as I tried the 150, they took it back to P1, P1's only comment was the 50mp back was not designed around a tech camera thus there will be some compromises. NOTE, same issue happened with the 100mp, and again P1 did not catch it. However in later LCC updates they did make a fix for the 100MP backs, but I don't believe it was ever dropped down to the 50MP. I state this because I have used 10.1 on some of the 50MP files I still have from testing and I still see the banding. It is made much more noticeable with clarity or contrast added to skies. On the 100MP backs, I believe it's fixed. EDIT: I just reworked a quick set from the IQ150, and the banding I mention was clearly visible in the LCC before processing, however after working on it in C1 10.2 the banding does appear gone, so P1 must have worked on this some more.
With all this said, I did not purchase the 50MP mainly due to the crop factor, as I mainly use wides and many times I could not move back 10 to 12 feet without compromising my shot. Live View is a huge bonus and with a tech camera even greater. Knowing that the image is in focus for sure via the P1 LCD LiveView was a huge advantage over my IQ260 and really made it hard to stay with that back. Wifi on the 260 was never that good, at least on mine, and it's not available on the IQ150.
The 3 attachments below are an example from a 15mm shift to the right with the 40mm Rodenstock. You can see the LCC as taken, then processed, (very nice overall) and the 2nd series shows the actual image before LCC is applied, the image takes on a noticeable red cast on the right far edge, but not as bad as I remember. The LCC applies very clean and pretty much evens out the shot for both light loss and color cast, noticeable in the water and on the rocks. The last shot is just a bit of work up to get the shot closer to where I want it.
I really can't see P1 making a back just devoted to a tech camera due to sales numbers, but anything is possible I guess.
Paul Caldwell