After Effects region of interest

Here’s the one-sentence summary of this post:

You don’t need to run the 64-bit kernel on Mac OS X to run 64-bit applications (like After Effects CS5).

Now that I’ve written that sentence, I can spend the rest of this post elaborating on it. But, really, you can stop reading now.

The 32-bit Mac OS kernel can run 64-bit applications, and it can manage ~32GB of RAM. With any current computer, there is no disadvantage to running the 32-bit kernel. Running the 32-bit kernel will not change which applications you can run, and it will not change how much address space your 64-bit applications can have.

The design of Mac OS separated the kernel address space from the client (application) address space, which is why Apple can fully support running a 64-bit program on a 32-bit kernel. On Leopard, this is the only option; and it’s the default on Snow Leopard.

This article explains the distinction between a 64-bit kernel and 64-bit user processes (applications) pretty well. This article is pretty good, too.

So, to say it again, 64-bit applications will run on Leopard (10.5) and Snow Leopard (10.6) versions of Mac OS X running their 32-bit kernels.

For Windows, you need a 64-bit OS to run 64-bit applications, and you need a 64-bit OS to use more than 4GB of physical RAM in the machine.

I’d point to the system requirements page here, but we haven’t updated it for After Effects CS5 yet. So, I’ll just tell you that 64-bit Windows 7, 64-bit Windows Vista, and Mac OS X 10.5 or higher are the operating systems that After Effects CS5 will run on.

[UPDATE: The system requirements for After Effects CS5 are public now.]

(Sorry for the rambling, somewhat redundant post, but I wanted to make doubly sure that this piece of confusion—which I see repeated everywhere—was nipped in the bud regarding After Effects CS5.)

For more information on After Effects CS5, go to Michael Coleman’s blog and sign up for the CS5 launch event.

There’s a lot of talk right now about what’s coming with After Effects CS5. Those of you who have already upgraded to After Effects CS4 will need to wait until April 12th to find out about all of the additions and improvements in After Effects CS5.

But there are some of you who are still using After Effects CS3. For you, the upgrade to After Effects CS5 is going to be an even greater advance, because you’ll finally be able to take advantage of the improvements that we made in After Effects CS4.

So, when you’re thinking about making the move from After Effects CS3 to After Effects CS5, don’t forget about this other great stuff that comes along.

Michael Coleman just announced on his blog that the details of After Effects CS5 will be released on 12April2010. On that day, I’ll be publishing the entire After Effects CS5 Help document, which will include detailed information about all of the new and changed features. I’ll also be accumulating links to other people’s feature summaries, reviews, and such on this blog.

You can sign up for the CS5 launch event to get additional news.

As most of you know, you can add comments to the pages of After Effects Help on the Web. We encourage you to add comments to share tips, tricks, links to tutorials, and other information that will help other users of After Effects.

Also, Adobe hosts a very active After Effects user-to-user forum. Many of the people who add comments to the pages of After Effects Help to provide useful information are the same people who help to answer questions on the forum.

I’d like to thank these folks for helping out their fellow After Effects users. This community generosity is one of the things that makes me so glad that I’m lucky enough to have the job of working with After Effects. It seems that the people who use After Effects are very often willing to help each other out. I like working in a community where everyone tries to help each other succeed in their art and work.

It would be nice if you did what you could to thank these people, too. You could stop by their websites, leave a note of thanks, consider buying what they’re selling… even use the PayPal donation buttons that some of them provide.

Here is a list of people who have been helping out a lot lately:

• Lutz Albrecht (Mylenium)
• Michael Szalapski (Szalam)
• Sébastien Périer
• Rick Gerard
• Andrew Yoole
• Steve Patterson
• Dan Ebberts
• David Bogie (bogiesan)
• John Dickinson
• Adolfo Rozenfeld
• Gyorfi Szilard
• Shabaz Bhat
• David Torno
• Bruno Quintin
• Jeff Foster
• Jorge Mochon
• Lloyd Alvarez

(Note that this list doesn’t even consider the work that some of these same people do as Community Help moderators, moderating the comments that are added to Help, which is itself a valuable service.)

Of course, there are a lot of folks who help out in other places, too, like all of the people answering questions on Creative COW forums, MoGraph, and so on. I’ll leave it to the folks running the respective leader boards on those sites to call those folks out. I will say a general thanks, though. There are a lot of places to get help for After Effects. Take your pick.

Again, thank you, all. I’m sure that everyone reading this thanks you, too, but I’ll let them speak for themselves.

This advice is similar in spirit to the advice given in a previous post, “Performance tip: Don’t starve your software of RAM.”

In many cases, performance is improved by using fewer than the maximum number of processors for Render Multiple Frames Simultaneously multiprocessing, even when you have enough RAM for all of the processors.

After Effects is a multithreaded application that can also use other forms of multiprocessing beyond just Render Multiple Frames Simultaneously multiprocessing, and it is possible for the processors to become “overscheduled” if these threads are competing for the same resources as the background processes used for rendering with Render Multiple Frames Simultaneously multiprocessing.

Therefore, the best approach is to begin by using a small number of processors for Render Multiple Frames Simultaneously multiprocessing; and then increase the number of processors used until you find the optimum number for your computer system and compositions.

For an 8-core computer system, the optimum number of processors may be 4 for some compositions, 6 for others, et cetera.

Run your own tests for your own scenarios. Remember: The reason that these settings are preferences is that the optimum values are different for different computers, compositions, and so on. There is no one “right” setting.

Keep in mind that using the Render Multiple Frames Simultaneously multiprocessing feature does not speed up the rendering of all compositions. The rendering of some compositions is memory-intensive, such as when you are working with very large background plates that are several thousands of pixels tall and wide. The rendering of some compositions is bandwidth-intensive (I/O-intensive), such as when you are working with many source files, especially if they are not served by a fast, local, dedicated disk drive. The Render Multiple Frames Simultaneously multiprocessing feature works best at improving performance when the resource that is most exercised by the composition is CPU processing power, such as when applying a processor-intensive effect like a glow or blur.

For tips on improving performance, see “Improve performance” in After Effects Help.

For details of RAM usage in After Effects CS5, see “Memory (RAM) usage in 64-bit After Effects” in After Effects Help.