Adobe Lightroom RAM requirements

[Hexadril]

Hi there!

I am looking for some advice on a sensible amount of RAM in a 2008 Mac Pro (8800GT) used primarily for Adobe Lightroom.

Let's assume a minimum of 8 GB (6x1GB on top of the pre-installed 2x1GB) versus 16GB or even more.

From what I read so far, there is a definite cutoff point where Photoshop (not Lightroom) stops using RAM for itself but instead free RAM is used as an adhoc scratch disk. Please correct me if I am wrong.

My question is obviously: Does anyone have experience running LR on a MP with a generous amount of RAM and how does it affect performance? Is the LR engine so close to Photoshop that tests and benchmarks can be used to judge LR performance and maybe RAM increase cutoff points?

Note: I am looking to optimize speed while working on RAW files, the speed of large batch file changes is secondary to the speed while working a specific picture.

 

[hodgjy]

I have no experience using that much ram and Lightroom, but I can say this. I have an iMac C2D 2.0 ghz. When using Lightroom with 1 gb ram, it ran very well. I don't have super long batch jobs, but I do take the time to edit many pictures at one time. I upgraded my ram to 2.5 gb about a week ago, and I only noticed a very small gain in performance. I think the biggest thing that slows down Lightroom is the size of your photo database and all of the thumb previews when you are searching through a series of many photos. Editing itself is great with 1 gb to 2.5 gb ram, so I image 8 gb would be awesome. I'm only guessing here, but I don't think you'll see much gain with going from 8 gb to 16 gb. I think 16 gb would only be useful if you plan to run Photoshop at the same time as Lightroom as your external editor. Lightroom as a standalone should scream along with 8 gb.

Just my opinion. YMMV.

 

[Hexadril]

Ah thank you, that certainly gives me an indication that Lightroom is less RAM hungry than I had suspected.

Still would be nice to hear from someone that uses Lightroom on a daily basis with 12MP RAW files.

Though right now I am leaning towards going for 8GB total and perhaps upgrading the RAM in a year or two when/if the applications can openly make use of it.

 

[hodgjy]

Here's a shot of my Activity Monitor so you can see some of the ram requirements. This computer was booted about 7 hours ago and I ran Safari, Mail, Excel, and iCal. I exited them and ran Lightroom. Lightroom was loaded while this picture was taken and the library is open with about 200 RAW images from a Canon 20D (8.2 mp) awaiting editing.

I hope this helps some.