Preview vs. Render - Differences with FX

Eddy Bee wrote on 6/9/2012, 3:46 PM

I just installed the free trial of Particle Illusion For Vegas. Really excellent, but I'm seeing a discrpency between the preview and renders.

The emitters appear larger in the Preview window than in the final rendered video. For example, a fireworks emitter will fill the entire video frame when previewing, but in the rendered file, the fireworks are smaller, filling only about half the frame.

I've also noticed something similar with VitaScene. Glows and sparkles look very large and promnient during preview, but when rendered, they're much smaller, sometimes to the point of being unnoticeable.

I've also seen similar behavior with some of the NewBlue art effects.

I'm using VP10, but I also remember seeing similar behavior when I was on VP8. (I know PI isn't certified for VP10, but so far, it seems to be working.)

I've tried tweaking my preview and project settings, but so far, I haven't been able to get the preview and renders to match when using the above effects.

Any insights or suggestions would be much appreciated. Thanks.

Comments

Grazie wrote on 6/9/2012, 4:36 PM

I'm getting the SIZE seen in Preview rendered-out correctly. I'm using one of the Fireworks Particles too.

Specs: 1440x1080i Media in a 1920x1080i Project rendered to MPEG2 for DVD prepping.

Cheers

Grazie

Eddy Bee wrote on 6/9/2012, 6:04 PM

Thanks for the reply. After poking around further, I think I hit upon something...

If I select a full preview mode, such as Good (Full), AND ALSO select the "Scale Video to Fit Preview Window" option, then the FX appear at the correct size; i.e., they match what gets rendered. This is true for both Particle Illusion and VitaScene.

This is the only combination of settings that seems to work. Unfortunately, these settings also significantly slow down my previews. Normally I preview using an "auto" mode with no scaling.

TheHappyFriar wrote on 6/9/2012, 7:26 PM

It's not just PI (I haven't tried), I've seen it in stock FX. The issue is because the FX is rendering out at a different resolution then the preview, so it's not exactly what you're seeing (don't use the nw OFX plugins much, I'm talking about the older DX ones). For PI specifically, this most likely is because PI is getting the preview resolution from Vegas and using that instead of the project resolution and have it scaled down by Vegas. It might be because of OpenGL/GPU/DX, or could be the OFX image processing workflow.