Oops, I forgot to mention, I'm using lr4 for windows (64bit) and previously used lr3.6(64bit) for windows. The a77 is using firmware 1.05 but previously used 1.04 with the same problem.
+1 for me
I've found a temporary workaround. Can anyone advise me if this is 'dangerous' for my raw files?
1. Copy .arw files from camera to computer
2. Run exiftool -lensmodel= *.arw
3. (lots of .arw_original backups are created)
4. Run alphalensinfo *.arw
5. Import into lightroom 4.
Step 2 blanks the lensmodel tag in the .arw file. Then, alphalensinfo creates the aux:lens tag (with the correct lens name in ). The LR4 import process discovers the lensmodel tag is blank and moves onto the aux:lens tag and everything appears normal in the library module, just like in LR3.
The catch is, I'm keeping duplicate backup copies of my original .arw files, just in case my little process is damaging them in some way.
Is anybody from adobe interested in this?
+1 for me to. I used exiftool/GUI to update arw files for a Tamron lens from my A700 and it worked fine under LR 4. However my new A57 does not work under 4.1 RC2.