>Secondly, if I put the supersampling to 2, does that mean that my dv video at 50% will now be at 29 fps again?

This is not what supersampling is for. The idea that it is good for slow motion comes from old marketing material and is not accurate.

"Resample" is the thing you want. Right click on your event and make sure the resample switch is set to Force Resample.

From Vegas help:
Vegas will resample video frames

By RESAMPLING your 15fps footage, Vegas will generate 30fps by simply blending two adjacent frames to create a new one between each of the existing frames in your media - thereby bringing the total frame rate up to the level demanded by the velocity envelope / project frame rate.

Not sure I'm understanding, so I need clarification.

If one were to take a clip (30fps) and reduced it to 15fps, then played it back (presuming a 30fps playback), wouldn't that make the motion within the clip appear faster?

J--

Thanks cheesehole, I guess I read too fast through the other long thread to catch that.

By the way, that sounds funny... "thanks cheesehole." Kind of like, shut your keg hole that my wrestling coach would always yell at us when we were talking during practice! :)

VC, The short answer is yes. But you are assuming that you play the entire clip. If you halve the velocity, you double the clip length. But if you use 1second of video @30 fps, and you lower the velocity to 50%, you get 2 seconds of video @15 fps. So in your example for your one second of vid at 50%, adding sampling, you get 30 fps for the one second and then 30 fps for the second. If you keep the time variable constant, such as a one second gap on the TL, the motion is slower.
Or, if your one second clip @30fps, is reduced to 15 fps, without sampling it appears faster because you knock out every other frame. I hope this helps and doesn't add to the confusion. John

>>>If one were to take a clip (30fps) and reduced it to 15fps, then played it back (presuming a 30fps playback), wouldn't that make the motion within the clip appear faster?

If you have a 15fps clip to start with, and you wanted to use it in a 30fps project, just drop it on the timeline. Vegas will automatically resample your clip so that it has enough frames to play on a 30fps time line without affecting the speed of the motion within the clip. There are two ways it can do this... it can either clone existing frames from your media to fill in the gaps, or it can generate new frames by blending adjacent frames - giving you a softer look. To control it, just enable/disable resampling by right clicking the event and choosing from the switches menu. This is all in the help/manual.

If I didn't answer your question, please clarify what you mean by taking a 30fps clip and reducing it to 15fps.

Just to add to the confusion, try this:

1. Take a clip of some fast moving video. Put that event on the timeline, right click on it, select Properties, and select "Disable Resample."

2. Ctrl-click and drag the right edge and move it to the right as far as it will go. This will set a playback rate of 0.25 (you can also set this in step 1 while you are in the Properties dialog).

3. Render this slo-mo clip.

4. Now, add a Supersample envelope to the Video Bus track. Set it to 3 for the duration of the slo-mo clip.

5. Render this clip.

6. Place both clips on the Vegas timeline and play them both back through an external NTSC monitor, (You MUST play them back to the external monitor).

What you should see is that without Supersampling, you will get interlace flicker. With Supersampling, this flicker is gone.

You can also demonstrate this by applying a velocity envelope in step 2 above, and setting the motion to reverse slow motion.

I am not claiming that Vegas Supersampling is actually doing any actual supersampling in this example, but I AM claiming that it isn't leaving the video untouched. The video is definitely changed.

The improvement when using Supersampling in this instance may be what has lead some people (including me) to think that Supersampling could improve slow motion.

Nice observation john. I was able to reproduce the effect using your steps. Enabling supersampling got rid of the interlace flicker for 3 out of every 4 frames in the result.

But actually, I didn't have to even use slow motion video to get the de-interlace effect. It seems to work as a de-interlacer on normal video too - with some caveats...

A couple more observations:
1) Using resample instead of supersample gave far smoother slow motion (because it generates interpolated frames)
2) Using supersample on top of resample seemed to have no additional effect
3) Using supersample on progressive material that has not been slowed down CREATES an interlace flicker
4) There shouldn't be interlace flicker in EVERY FRAME of the non-resampled footage!!! Why the heck is that there in the first place? I would expect interlace flicker when the frame changes (every 4th frame after slowing down to .25%)

Conclusions?
1) Why does slo-mo flicker so bad in the first place when resample is disabled?
I think disabling resample on interlaced footage and then slowing down the clip kind of mucks it up. Vegas needs to resample the footage in order to de-interlace it properly - otherwise it just shows the same interlaced frames for 4 frames, then moves to the next one! Not very smart. The help file does indicate that resample can solve interlace problems.

2) Why does enabling supersample on un-resampled slow motion interlaced footage fix the flicker?

What supersample is doing in this case is actually de-interlacing - using "interpolation" and it is only using the upper field for some reason - even if I change the field order setting on the media.

Is it useful? I guess if you want to render slow motion interlaced video without resampling (to avoid getting blended frames) - to an interlaced format - this would be the way to do it. Disable resample, and enable supersample (2 does the trick).

BUT be aware that you are throwing away all the lower fields of your source video.

You can accomplish something very similar by disabling resample and instead of enabling supersample, enable "Reduce Interlace Flicker". This will do a "blend" de-interlace operation which gives you both fields blended together... it's down to which look you like better in the end. Blended fields or interpolated fields.

I was actually looking for a way to get Vegas to eliminate fields at the event level... but this supersampling method is too unpredictable. It makes progressive footage flicker, and it doesn't let you choose which field to use.

What would solve this problem is if the media properties allowed you to not just choose "Reduce Interlace Flicker" but to choose which method to use "Interpolate" or "Blend". The project level setting doesn't seem to have any effect on it.

- Ben