@johnnyrr

I wouldn't have thought to look for an fX to do Slow Motion without you bringing the problem to the forum. It's working OK for me on the system from my signature with 120 fps video source.

Have you tried doing slow motion the old fashioned way? That process has worked for years and years and years and years.

I found the Vegas fx plugin does not crash my computers which have amd cards. But I found it difficult to control. Because I used it in conjunction with an animated bezier mask and about 4 instances of secondary color correction and everything shifted when I applied the slomo fx. Plus it was doing allot of unnecessary interpolation... I shot at 120 fps and all that was needed was to drop the frame rate to 30 for 1/4 speed. Found it better all around to edit and render out of Vegas 18 at the full frame rate and knock it down to 30 externally with ffmpeg or vDub2 using its ffmpeg codec option. It does recompress the frames but at least does no interpolation or mask shifting.

This process works well with my NVIDIA RTX2080 card.

@Espadon My dynamic RAM preview is set to 1000, but I can't remember what the default setting was (above or below 200)? Are you suggesting that utilizing more RAM than the default is better... or not as good? I would think utilizing more RAM would be better?

I also tried your suggestion to render out the clip in slow motion before trying to use it... seemed like an excellent idea. But, it crashed my computer. I rendered it w/o using "GPU assist" but I think I may have had the "GPU acceleration of video processing" turned on in the Video Preferences Tab? I wanted to double check it, but...

Upon reboot, there was an error when I tried to launch Vegas (error code -59, "You don't have the license to use this software"). Not cool. After doing some research, it appeared that the best solution was to uninstall / reinstall Vegas. I did that and Vegas was running again. But now, each time I launch Vegas it goes thru the license validation process (it should've only done it the first time after installation)... which takes a few extra clicks and about 20 seconds of time to say my license is activated. I'll have to figure out how to eliminate this little bug now.

However, I still wanted to see if I could run the slow motion plugin. So, I rendered it out with the Magix Intermediate HQ codec. It was a 3 second clip that I setup at 30% speed so I rendered out 9 seconds. It didn't crash my computer but took about 35 minutes to complete the render. Wow, incredibly slow, but I'm not sure if it was completely the fault of the slow motion plugin or the Intermediate HQ codec (since I never used that codec before). The payoff was the worst part though.... the clip look horrible after reviewing it, very poor intermediate frames, did not look natural at all. I used it on a clip that was handheld and panning so maybe it was a poor choice for the plugin??

@johnnyrr

I wouldn't have thought to look for an fX to do Slow Motion without you bringing the problem to the forum. It's working OK for me on the system from my signature with 120 fps video source.

Have you tried doing slow motion the old fashioned way? That process has worked for years and years and years and years.

@john_dennis I was using the slow motion vfx with 29.97fps footage. It's supposed to create new intermediate frames so the footage can be slowed down. If I had 120fps footage, just reducing the rate to 1/4 speed would work perfectly and there'd be no need for this plugin. However, if you wanted to create a 10% speed with your footage, then you'd need something like this plugin to achieve a good looking / smooth clip. Unfortunately, I have not had good luck using this plugin yet.

@johnnyrr

I used the Slow Motion fX on XAVC-S UHD 29.97p and rendered successfully with these results:

UHD 30P Analyze Fine PB Rate 0.5

UHD 30P Analyze Fine PB Rate 0.33

UHD 30P Analyze Fine PB Rate 0.25

Compare that to FHD-120 FPS media of the same subject at twice real time:

...or the same subject at four times real time:

It becomes very clear: miracles only exist in fairy tales.
In (video) technology you should create the best possible conditions during the recording and not rely on the possibilities of the software in post-production.

That's very insightful. I try my best to do everything perfectly during the shoot but more often than I like find myself dreaming up creative ways to cover up my lapses somehow in post. Flexible software helps. B-cam may be the best insurance.

@walter-i.

An astute observation.

That's very insightful. I try my best to do everything perfectly during the shoot but more often than I like find myself dreaming up creative ways to cover up my lapses somehow in post.

Unfortunately, that's the way it is with me again and again.😰
It's just a hobby for me

@john_dennis
Also from my side: Thank you very much for this informative comparison.

The payoff was the worst part though.... the clip look horrible after reviewing it, very poor intermediate frames, did not look natural at all. I used it on a clip that was handheld and panning so maybe it was a poor choice for the plugin??

You don't get twixtor quality optical flow slow motion with VegasPro. It makes too many mistakes. There's twixtor and Happy Otter Tools as Paid options, and Davinci Resolve as a free option. They are similar in quality. I don't use Vegas slowmo. it's not dependable, and interface buggy

It would be better if the TO uploaded their source footage so someone who has Vegas and Twixtor could render a comparison.
Commercials are of no use because there is no comparison.
And - as already mentioned above - miracles only exist in fairy tales.