It looks like a bug affecting frames with alpha channel and zero opacity. If you use PI on an event with full opacity (e.g. a solid color generated media or a video clip with full opacity) PI and levels work correct.

What you can do is applying PI onto a black framed event (generated media: solid color) and then using track composite mode "multiply".

It would be overlay or hardlight on 125 = grey and add or screen for 0 = black

What you can also do is render your clip solid black and use the lumens of particle as a mask.
So duplicate the track = multiply and add mask gen to multiplied track = parent multiplied track for overlay.

You are right, "multiply" doesn't work the way intended for black, it's "add".

Wouldn't nesting fix this problem?

Bob.

Nesting a project with an pi event freezes Vegas Pro here. The only way I found to get it done quickly is using compositing.

Robert_NY,

I use PI standalone too and PNG sequences with alpha like most. I also tend to create subtle or glowy or whispy stuff -- and have actually created my own version of one of the Aurora -- and so I also want to retain as much of their in-PI presence. I've never nested but I do tend to use duplicates of the particles, one on the top track at 100% composite, the other on a track under it at 50% or whatever works.

I can use basic Source Alpha and/or use Add; if Add is too intense I can bring down the composite level or use Screen on one or the other. Then if necessary, I slightly tweak one or the other to kind of "bring back" or beef up the overall particle. Sometimes even changing the color of one or the other can be interesting, i.e. keep the high end white if it is that, the mid and other a slight coloring.

I don't use Levels much for I'm more of a Color Curves and Color Corrector/Color Balance guy since none of my stuff has to conform to broadcast standards, just online viewing. My visual style is also rather ethereal or artsy and so I have more latitude perhaps on experimenting.

Naturally, whatever one's particles and whatever one's tweaking choices depends on the footage over which the particle is doing its thing, so there is no formula I can offer.
Rely on your own instincts and preferences to get the particle presence you want.

You have to keep in mind solid illegal black = 0 is need for compositing you don’t want to use broadcast standard levels in-between.

Thank you all for your input. I have some time today so I will try the above methods and see how it goes.

Update is good, although somewhat confusing. At least to me.

What works... Nesting the PI project and using the levels plugin on it. However, I did have to put a solid black event at the bottom of the PI project first.

What's confusing... In the PI project itself, adding the solid black event still did not allow the levels plugin to work, even with using various compositing methods. I also noticed that just just enabling the levels plugin with the defaults (no level adjustment) wiped out the particle.

What actually happened was that the last 1/4 of the event in the PI project is overlapped (underlapped actually) by the next scene, when I nested the PI project and applied the levels plugin the PI only showed up in that last section. That is when I added the black event in the PI project and this worked.

I still believe it can be made to work in the original. I am not a master of compositing and I'm sure I just haven't figured out how to set up right.

Not sure how you did this. Adding a black solid color generated media in addition to an existing pi filtered event is not supposed to work different. But applying pi onto a black solid color event and then using "add" compositing mode to combine with another video event (in a track below) should work.