I have read that quite a few people are happily opening their raw files from a Fuji S5 Pro with ACR 4 & 4.1, but have any of you managed to get it to recognize the full 12M pixels. At first I thought it was me, new camera & all that, but then I opened a raw file in iPhoto & there it was in full resolution.
I'm guessing that ACR is not able to see the S pixel data in the image & is therefor only opening the remaining 6M R pixels, or visa versa.
I am using a MacPro & G5 with 10.4.10 & CS3 Design Premium with all the updates.
The S and R sensors are not there to increase the resolution, but the dynamic range. You can select the number of pixels that you will export as they are interpolated anyways. (Click on the hyperlink at the bottom of ACR windows for workflow options)