Adobe Bridge vs Lightroom 4
I am accumulating a huge number of photos that I need to organize and catalog. People have encouraged me to get Lightroom, but my OS on my Mac is 10.6.8, and Lightroom 5 is only compatible with 10.7 or 10.8. So I would need to purchase Lightroom 4 through Amazon. However by the time I get a new computer with an OS that is compatible with newer versions of Lightroom, LR 6 will probably have been released, and knowing Adobe, I'm concerned that I won't be able to upgrade from LR 4 to LR6. Also, I already have Photoshop CS6, so I could use Adobe Bridge. So, my question is: is Bridge as user-friendly as LR is supposed to be, and will I be able to catalog my photos as efficiently in Bridge? Thanks for your input.