What the heck is bridge doing?

Why does bridge hold me hostage every time I open a new folder?

Today I downloaded 136 photos(large jpg and large raw files from a 5D2) onto my computer. When I opened the folder for the first time in bridge it slowly made thumbnails for the images and would not let me take any actions for about 5 minutes until it had processed them...

What exactly was bridge processing?

Bridge builds a cache of the images in a folder when it is opened the first time; this speeds up viewing when you revisit to folder later.

If you look in the lower left corner you will see a circular arrow icon....when its spinning it means that Bridge is building the folder cache.

I recently upgraded from a 50D to a 5D2. I only shoot RAW and I also sing and watch and wait - not like in "Waltzing Mathilda" till the billy boiled - but till Bridge has processed all these large raw files into thumbnails. The 5D2 files are a fair bit larger than the 50D and that costs time.... Also in loading and saving in high quality I need to be more patient these days.

"Waltzing Matilda" might be OK for a few times, but I'd get your MP3 collection built up for the future...