I have had a play with a Credo 60 and its LiveView feature which operates through the back and untethered.
I have been offered a used Aptus II 12 R but need to know whether it has the same in-camera LiveView function and how it compares to that of the Credo's.
If it does, is its functionality the same?
Rogerxnz
Take a good look at the live view functions of the Credo and IQ backs before you go for one. Don't expect it to be anything like live view on DSLR cameras.
Due to the common name one might expect similar performance, but it's not even close. Still useful but "live" is kind of pushing it. Image quality of the live view very much depends on lighting conditions both in front of and behind the camera. Refresh is also very slow on MF backs. It's no better connected to a laptop either.
Also the fact that the older backs don't have live view on the backs is not the end of the world. The refresh rate is so slow that it's not really that far off from shooting and reviewing... so you are not missing that much.
If I were you I would hold off and see what comes out from other brands at Photokina. There may be a cmos coming from someone with better live view.