Lightroom 4.1 Running SLOW!

[hhelmbold]

I keep all my RAW files in CR2 format, could that be the problem?

Yes, that's it - the solution is convert them to dng and check the "embed fast-load data" option, that's specifically made for speeding up raw rendering. You can still embed cr2 in the dng if you never ever want to loose the original format, though of course required hd doubles. Personally, I like dng since all programs I ever looked at (except dxo) work with raw dng nowadays.

Sorry guys but I have to disagree... I know a lot of people preach converting to dng but I found that DNG IS the problem for Lightroom being so slow. I run an i7 processor with 24GB of RAM and when I convert to dng, I will click on the crop tool, wait 10 seconds... crop... wait 10 seconds... adjust a slider... wait 10 seconds etc etc. All my other catalogues are in CR2 format, so it made me think and I came across this article : http://www.foto-biz.com/Lightroom/The-case-against-dng

I kept the dng files I already worked on, deleted the rest from the catalogue and re-imported the CR2 files from the memory card... Suddenly Lightroom was working the way it is supposed to again. So my experience tells me that the dng file is indeed the problem.

[Marsu42]

So my experience tells me that the dng file is indeed the problem.

Did you use LR4's dng version with "Embed Fast Load Data"? That's exactly made to speed up rendering, though at the cost of a bit larger filesize - and still smaller than the original cr2.

[Mt Spokane Photography]

I've run tests on DNG converted files with my D800.  The time to render them is faster, but not by much. 

[JMA]

I’ve only noticed LR 4.3 running painfully slow just recently, I’ve done heaps of searching but nothing people were recommending was fixing it, so I thought, what have I changed in the last month, then I remembered that I installed a new anti-virus, (bitdefender), where previously I was using AVG, so I uninstalled it, LR is now running perfect.
Not sure if this will work for everyone, but it might be worth a try.