Which iMAC is best for photoshop & lightroom

<p>I am going to buy an iMAC 27" (the latest one) - but I am not sure which specs is most important for photoshop and lightroom.<br>

Is it:<br>

-i5/i7<br />-video card 500mb vs 1GB<br />-RAM 4GB<br>

I know all four impacts the performance - what bothers me the most is when I open a file from lightroom to photoshop. Currently, it loads on my computer for 1 full second and the same when it closes. So i want the loading time to be quicker basically....<br>

Which one should I care about most?<br>

Cheers</p>

Whatever you buy, an upgrade to 8GB is straightforward and fairly inexpensive. It results in a dramatic improvement. It's not a decision you have to make before you buy. Even if you ask Apple to configure an iMac that way when you buy, they just pop it in after opening the box.

The second biggest factor is disk speed, but I'm not sure you can do much about that with an iMac. Maybe add something external using the newest and fastest interface (Thunderbolt)? I don't know what is currently available, as Thunderbolt is so new. But, again, it's not a pre-buy decision.

Compared to the above, CPU and video speeds are minor factors. So, if your budget is fixed, it makes sense to save money on CPU and video speed and spend it on (1st) RAM and (2nd) fast disk. You can defer both of those decisions if you don't have the money right away.

If you do have the money, getting a faster CPU and video card do make sense since these can't be changed later (without a great deal of trouble and expense).

<p>The i7 may be quicker for some tasks than the i5, but I'm not certain. Check with Adobe to see if it uses the graphics card for any processing. If it doesn't, and you don't do gaming on your iMac, go for the less costly option. However, Marc is correct, in that as these things cannot be changed later, if you can afford them, do them now.</p>

<p>RAM: You'll want as much RAM as you can afford. Current iMacs have four RAM slots, and can address up to 16GB. Whatever you do, DON'T pay Apple's prices for RAM. Get it with the minimum RAM that fills two slots (usually 4 GB). Buy your RAM from a reputable place like <a href="http://www.macsales.com">OWC</a>. I just paid $99 for a extra 8GB (2x4GB) for my Sister's late 2010 iMac. She now has 12GB.</p>

<p>Another option to consider, if you can stomach the $600 cost, would be to add a 256GB Solid State Drive. You'd get the iMac configured with the OS, applications, etc. all installed on the SSD, and have a blank 1 Terabyte disk as well for photos, etc. If you can leave enough space on that for your PS "scratch files', you should have a very fast machine.</p>

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<p>Currently, it loads on my computer for 1 full second and the same when it closes.</p>

</blockquote>

<p>The largest bottleneck will be if you are keeping all of your media on the internal drive. You need a fast external drive for you media. Even then, getting betting than 1 second is asking a lot. I have a 2.8 Quad Core Mac Pro (Zeon) with a Raptor boot drive, 10GB ram and all my media is on external eSata towers and it still takes me a couple of seconds to save a PSD. The only thing that is going to speed that up is some sort of hard drive RAID... and I am not going to jump through those hoops.</p>

<p>The current iMac design bums me out because it's more difficult to get into. You basically have to order a SSD from Apple if you want one, and Apple does not ship the fastest or best SSD drives. SandForce controller based drives, such as OCZ Vertex 2 or OWC Mercury Extreme Pro drives, are much better.</p>

<p>But I agree it's going to be hard to beat the load times you're already seeing. Unless you want to store your images, or at least your current working set, on SSDs, which can get expensive.</p>

<p>I'm running an i7 27" iMac with 8GB of RAM, 512mb VRAM and a 1TB internal disc. I open, process, sharpen and close 12mb RAW photo files to and from ACR and CS5 all day long. The 1 to 4 second delay is of no consequence to me. In fact, reading that sentence just took you longer.<br>

In practical terms it's gives me just about enough time to move the mouse pointer up to the close button or reach for the cocktail. <br>

When I upgraded from the standard 4GB of RAM (two 2GB sticks) to 8GB I did it by buying two 4GB sticks. The Apple store bought back the two 2GB sticks. This leaves me with two empty slots allowing me to upgrade to a full 16GB of RAM in the future.</p>

<p>i have a 2.8ghz, i7, 16gig ram and 1TB internal HD.... the images are flying ; )</p>

<p>Yes the i7 will make a difference, i test it vs a i5 with the exact same computer model, same file, same Photoshop etx.. the i7 was quicker.<br>

I ahve the ATI Radeon HD 4850 512meg video card and i dont see any problem.</p>

<p>I dont have the SD drive as i bought the first 27inch 2years ago.. but honestly, i have post speed test result last years and the result where pretty amazing.. was opening a 2GIG file in 10 sec or so i think.. and save this big file in less than 20sec i think.. a regular file from a MarkII open and close in a blink.</p>

<p>I have a Western DIgital RAID disk connect with firewire 800 for backup purpose only, never acces file on it directly.. all is on my Imac, system, software and file i work on.</p>