Vegas 8c. I have the same max # of RAM for preview with or w/o motion blur: 1024. Doesn't matter what amount I set the motion blur to.

Xberk,
yes, you're testing it correctly.

The HappyFriar,
the amount of Preview RAM doesn't change. The amount of video it will hold is what changes e.g. No MB, I can buffer 16 seconds in my 1024MB, 4 frames of MB then my 1024MB will only buffer 4 seconds.

Bob.

ok. Here's my retest then:
0MB: 00:00:25;18
4frame MB 00:00:3;08

So I get a definite difference.

Thanks,
so as that was in V8 then a reasonable conclusion is its always been this way.

Bob.

Doesn't motion blur get applied globally to all tracks? There is a setting to bypass motion blur on each track, where it isn't needed. See if that improves RAM usage. My experience with motion blur is that it is a total RAM hog. The only ways around it are to reduce the preview quality or prerender.

Motion blur is applied to the Video Buss.
Don't know of anyway to bypass it on a per track basis. There is an icon to bypass buss FXs and MB. Bypassing it might improve the amount of video the Preview RAM can hold but that's not the issue. The issue is why does having MB decrease the amount of video the preview buffer can hold.

Maybe the answer is Vegas needs more RAM as more frames have to be buffered to calculate the motion blur. The more frames of MB, the more buffering Vegas needs to do internally and it uses some of the Preview RAM to do this. Not that this theory holds up well either. One way to stop Vegas going wobbly is to decrease Preview RAM so that suggest Vegas holds it and will not use it, even to prevent a crash.

Bob.

> Don't know of anyway to bypass it on a per track basis.

Er? Unless I don't understand your concept of tracks, do you mean Events=Time(?), then slap in a MB Envelope and add points for the MB? - But I'm guessing you knew this already?

Grazie

Now I'm confussed :)
Original statment by Jabloomf1230:

"There is a setting to bypass motion blur on each track, where it isn't needed."

Darned if I can find anyway to do this. I did look and I can see no switch that causes a track to bypass MB or being routed through the Video Buss Master which is the only place where MB can be applied, via an envelope.

Yes indeed, the envelope means one can control MB over time however if two tracks have events being comped at the same point in time they either both get MB or they don't. No way to apply it to only one of those tracks and hence events.

Maybe I cannot find this elusive switch, if anyone can I'd love to be found wrong.

Bob.

I'm not at my Vegas PCs at the moment, but each track (not the Video bus track), has a little icon (looks like some boxes, as I recall, heh, heh) that if you click on it, will allow you to bypass motion blur, just for that track. Don't get your hopes up, though. I tried it last night, before posting my message and it doesn't help much with the RAM issue and motion blur.

I'm positive that this is included in the arcane Vegas help file.

Not sure how this works as I have not used MB for anything .. but I do see the icon on each track -- further explanations of uses for Motion Blur would be appreciated ..
Regards the preview buffer being reduced when using MB -- it just must suck up the RAM and thereby shorten the preview time- unless I'm not thinking of this right.

Motion Blue Track icon - Paul

Thanks "x". You saved me the trouble of posting my own screen shot.BTW,

I estimate (via Everest) that the motion blur effect uses ~ 1 GB of RAM, using Vegas 9.0d x64. The number of keyframes in the envelope has no effect, nor does bypassing motion blur on other video tracks.

For example, if you are running Vegas x64 with 4 GB RAM, you might have 2.5 GB physical RAM free under Windows 7 x64. If motion blur uses 1 GB by itself, you can see that you have limited how much preview RAM is available, no matter what value that you have it set to in Vegas. Of course, if you have 8 GB or 12 GB physical RAM, the influence of motion blur on the RAM pool becomes less pronounced.

I'm amazed at my own, what can I call it, lack of observation, stupidity??

I did or I thought I did, carefully check every icon in the track header and somehow completely missed that one. Having found it I thought, well OK, when did that get added. So I checked V4 and its been there all along, friggin hell. No excuse, back in V4 days I didn't need glasses either and still I missed it

I've used MB to repair problems in old tapes. It can work wonders if there's little or no motion to cover up dropouts etc or for noise reduction.

Its primary use is to add motion blur that is normally created by the shutter in a camera when compositing. Say you've created moving text. It can appear quite juddery due to the infinitely fast shutter. Adding MB adds motion blur helps prevent the judder. Use it in conjunction with Supersampling to get good looking motion blur.

You can also use it as an unnatural effect to add ghost like trails to moving objects.

Bob.

> You can also use it as an unnatural effect to add ghost like trails to moving objects.

Any chance of seeing a small snippet? Before and after? What's the Compo setup?

I have a job on that was shot in Las Vegas recently and would like to add this to some of the street scenes.

Nice one Bob!

Grazie

"Any chance of seeing a small snippet? Before and after? What's the Compo setup?"

Sure, except this took a bit as too much MB and my Vegas goes into red frame mode. Darn simple to invoke really.
Anyways here's ahot with increasing MB upto the max of 1 second. MB is asymetric gaussian.






Here's a demo of Superampling and GB. Starts with neither and then ramps MB to 1 frame and SS to max. Following that MB ramps upto 6 frames:




Just for anyone whose not familiar with Superampling, it only works with motion created within Vegas.

Bob.