1. Hard Drive and Scratch Disk Space
First off, check to see that you have at least 50% of your hard drive space on your computer available. If you are working with a hard drive that is more than 75% full (i.e. you only have 25% or less of your hard drive memory left) that can slow down all applications and especially Lightroom. And of course a fast computer is also a major factor, but Lightroom will work on just about any computer with recent software.
Also, increasing the amount of RAM on your computer will greatly help as well. In general, 2 GB of RAM is about the minimum for any computer running Lightroom or Photoshop. I highly recommend at least 4 GB of RAM if possible. The more RAM the better.
2. Render 1:1 Previews on or after Import
Make sure that you render the 1:1 previews during the import stage or after importing images into Lightroom. It doesn't happen automatically and this will greatly speed up everything in Lightroom. This is a little known key point to a fast workflow in Lightroom and I suspect the major cause of many folks finding Lightroom slow.
To render the 1:1 previews during the import process make sure to click the Initial Preview tab in the import dialog window as in Photo 1.
To render the 1:1 previews after import first select all of the images in the folder (in the Library module), then go to Library > Previews > Render 1:1 Previews.
If you don't want to take the time to render 1:1 previews for all of your images I would suggest rendering just the Standard Previews on import then after an initial round of editing building the 1:1 previews for your edited images. Basically, the point here is if you don't render 1:1 previews and you need to zoom in on images you'll be waiting for Lightroom to build those previews for every image you zoom in on. And that gets very frustrating so do yourself a favor and build the 1:1 previews early on.
3. Set Your Preferences
In the preferences (Lightroom > Preferences), under File Handling in the Catalog settings, you can adjust what size standard previews Lightroom builds from 1,024 pixels to 2,048 pixels depending on your monitor size. You can also adjust the Preview Quality (High, Medium and Low).
By adjusting these toggle boxes you can optimize Lightroom for your computer and monitor. I generally have Lightroom set to create 2,048 pixels for my large Apple Cinema Display and I also set the Preview Quality to high so that I can see the best quality preview as I edit images. Since I have my preferences set to the higher settings it slows Lightroom down just a little, but with 6 GB of RAM in my Apple MacPro it is a small difference and I prefer the higher quality previews. On my laptop, I set the previews to 1,440 as that is the maximum width of my Laptop's 15-inch monitor.
4. Optimizing the Lightroom Catalog
If you have your Lightroom catalog on an external hard drive (USB or Firewire) this can massively slow down everything in Lightroom as it is limited by the connection speed of the hard drive. I would suggest putting the main Lightroom catalog on a faster drive with a SATA connection or better yet leave it on the computers internal drive. Also, in 1.4.1 you can optimize the Lightroom catalog if things seem to be running a little slow. As in Photo 4, go to the Catalog Setting preferences (from the General tab in the main preferences dialog) and at the bottom of the General Catalog Settings window is the "Relaunch and Optimize" button. Click this and Lightroom will optimize your catalog for the best performance.
5. Embed Metadata and Keywords on Import
In my workflow, I have found that Lightroom works very well with Metadata and Keywording but if you need to alter large groups of images the software can drag a bit as you try to type into the metadata fields. This is less of an issue with Lightroom version 1.4.1 (and will be a non-issue from what I have seen in Version 2.0 Beta) but the fastest method I have found for importing metadata and keywords is still to do it as you import the images.
In the import dialog box there is a field for typing in keywords and the toggle just above allows you to create custom metadata templates which are now editable (finally). I have several metadata templates I use. If all of the images are of the same person, scene, location and sport then I create a custom metadata template with all of the metadata in it so once the images are imported the metadata and keywording is finished. If I am importing a group of images with different people, locations or sports then I will just use my basic copyright template during import - along with generic keywords. Once the images are imported I'll select groups of similars and type in the metadata for each group.
Review
If you don't render the standard-sized or 1:1 previews then Lightroom is constantly trying to build them as you edit your images resulting in very slow performance. And if your Lightroom Catalog is on an external USB or Firewire hard drive this to will handcuff Lightroom - just as working with an internal drive that is almost full will. Adapt these tips to your Lightroom workflow and you will be amazed at how efficient and fast Lightroom can be. And if that isn't enough, buy yourself a serious amount of RAM and then Lightroom with really start to motor. I recently worked on a friend's MacPro with 9 GB of RAM and Lightroom never hesitated for anything. Even exporting 100 images took very little time.
Also, if you start to see Lightroom crashing often you may have some RAM issues in your computer. I have had several peers recently deal with some serious computer issues, especially because Lightroom and many applications like it rely very heavily on the computer's RAM (Random Access Memory). The cause of their computer crashes and other issues was not the Lightroom software itself but a case of bad RAM chips. Once they replaced the RAM all of their Lightroom problems were solved. So if you start having massive issues with Lightroom and your computer crashing you might want to remove any 3rd party RAM you have installed and replace it.
Hope this is better... Sorry it's long winded.... maybe it will help someone along the way.....
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