I upgraded to LR4.3 and CS4. When I open a raw image in CS4 from LR4.3, the image quality is horrible. A message appeared that I need camera raw plugin 7.3, however, this is not available for CS4. Is there a solution to this problem or do I need to upgrade to CS6?
You updated but I'll post the following for anyone else who has the same question in future.
LR 4.3 is equivalent to Camera Raw 7.3. If LR and Ps aren't communicating well, you can export an image file from LR then open that into Ps. For 16-bit, choose TIFF with ZIP compression unless you don't mind an enormous file. 16-bit PSD is another option but its Background layer has no compression and will be the same huge size as an uncompressed TIFF.