Speeding up Render TIme- Selective Prerender?

goldentwig wrote on 5/21/2006, 7:00 PM
I might just a get a lot of laughs for asking this, but does anybody have any tricks or tips on how to speed up the render process? I have a 15 minute piece which has 8 regions in it plus a graphic intro. The intro is a Sony-generated text (3D alpha with compositing) that is over a cropped area of a ActionPack/JumpBack Animated motion graphic, about 15 seconds long. The rest of the segment only uses a few transitions (maybe 5 short ones) and overlays an alpha channeled Photoshop lower third with Sony generated text on top of it, 8 times, for about 2-3 seconds each.

Each time I've started to Batch Render the output in MPEG-2 for DVD Architect, Vegas wants between 8-10 hours to render this. Does anybody have any ideas on how to speed that up a little? Does using the "Selective Prerender Video" option actually do anything to improve the final render performance?

Thanks!

Comments

Chienworks wrote on 5/21/2006, 7:04 PM
Selective prerender can save final rendering time, but at a cost of eating up time before you start the render. No matter which way you slice it, it's still gonna take all that time. My advice? Start it and let it run. It'll finish eventually, and probably long before you can find out any other tips that may or may not help.
johnmeyer wrote on 5/21/2006, 7:17 PM
Network render is the ideal tool for this situation, if you have a few other computers on the network. Install Vegas on those (you can install on two machines for network render purposes only). You can cut the render down to about 1/3 the time it now takes, if those other computers are as fast as your main computer.
goldentwig wrote on 5/22/2006, 7:50 AM
Okay, great!! This was what I asked elsewhere and was waiting for an answer.... so you DO have to have Vegas installed on both computers to use network rendering, but it's allowed under our license agreement... Good!!

If the second computer is FASTER than the main editing computer, I imagine that will help increase the render speed even more? I'm looking at replacing a desktop on my network that just died last week and this would be a good thing to plan for when purchasing... Thanks so much!!!
riredale wrote on 5/22/2006, 8:38 PM
I do a poor man's network render--I open two instances of Vegas on the same PC, and use one of them to do the render. With CTRL-ALT-DEL you can set the priority of the rendering Vegas to Idle. Now you have full use of your PC with the other instance of Vegas, and rendering will take place when the processor is not needed by you. It's amazing to me how much idle time is available for a background render.
arem wrote on 5/22/2006, 8:38 PM
Is the rest of your video on the same track as the 3D Alpha? Whenever I do a project using the 3d alpha, it makes render time 50 times longer. I usually render the 3d part separate or make sure that it is only on one track for short periods of time.
Laurence wrote on 5/23/2006, 7:24 AM
Oh my God, I just read your post after trying to figure out why my current project was taking so long to render! I had "3d Alpha" selected on two tracks, even though it was only being used on a couple of seconds of one track. I started rendering a project that is about 120 minutes long last night, this morning after four hours of rendering it still had almost thirteen hours left to go and I was watching the render proceed at about a frame a second with just two layers of simple video!.

I rendered the small animation I needed the 3d alpha for, brought that render back into the project with 3d alpha turned off on all tracks, and now it is rendering like it should... which is to say it is going to take a couple of hours, but nothing like the absolutely INSANE amount of time it was taking with the 3d alpha!
johnmeyer wrote on 5/23/2006, 9:33 AM
Oh my God, I just read your post after trying to figure out why my current project was taking so long to render! I had "3d Alpha" selected on two tracks, even though it was only being used on a couple of seconds of one track.

This was definitely a big-time problem in Vegas 5, at least in earlier versions. Once you had even one second of this fX on the timeline, the whole darn thing slowed down to a crawl. The workaround was exactly as you describe: pre-render the affected sections, put those back on the timeline, remove the 3D, and then render the rest. As I remember, virtually any compositing would cause this problem.

I am pretty sure this has been fixed for awhile, but I cannot remember which release fixed it. Perhaps it is disclosed in the release notes.