Lightroom on the MAC installs both 32-bit and 64-bit versions and by default activates the 32-bit version. Which is fine. (Under Windows you have to select which version to install, so you guys don’t need to read anymore.)
When I opened the More Info panel for Lightroom it showed that indeed that “Open in 32 bit mode” was not checked. However, the credits screen did not show that Lightroom was running in 64-bit mode! I am sure that you know how to get to the info screen via Finder>Applications>Adobe Lightroom. Here is another screen shot to help.[singlepic id=69 w=320 h=240 float=left]
My solution was to select “Open in 32 Bit Mode” and then open and close Lightroom. Go back and then de-select the 32-bit mode and voila, when Lightroom opened, I’ve got 64-bit!
I have to say it is a gigantic difference, duh! Going from 3GB of RAM to 10 is going to make a difference. I just got the MAC and so when something isn’t right, I assume user error. After my discovery I was very excited and so I called several friends. To my shock it wasn’t me, they were not in 64-bit either and they knew what they were doing. I bet a lot of you are not in 64-bit mode either.
After the switch, Lightroom is now turbo-charged and changes made to images in the develop module are instantaneous. This is what I was expecting with the new MAC…WOW! So check your settings to make sure that you are also in WOW mode!