This seems very trivial on other software packages.
In maya if I have a particle simulation and I change the opacity it updates in the view port giving me quick feedback of what my opacity are.
In Houdini it seems like I need to use black magic to do this.
If I create a particle system add a color pop set my color and my opacity.
the color shows up on the view port but the opacity does not.
The way I am doing it right now is to copy spheres to the particles and transferring that opacity but that seems ver inefficient.
It has to be away in Houdini to let me see my point opacities.
i also try switching the display to sprites and this does not work.
does anyone knows the right way to do this?
Thanks

Point display is point display in POPs. By default it doesn't show opacity.

In POPs, just add a Sprite POP and enable the Scale parameter and set the size of your sprites accordingly. Now you will see the opacity.

See the example file attached.

jeff thanks for your reply,
but when I open your example file the particles
dont show up opacity
they just show up solid white.
if I set the opacity to 0 the particles dont show up.
is there anything else that needs to be done to this to get it to work?

You have to open up the viewport display options, go to Particle and set the option to sprite display in the viewport.

yup
I did that as well.
I am using houdini 11 with no results yet.

That sucks as it works for me on linux, mac and windows…

First thing is to make sure you are using a very recent build. I usually go with the daily build. H11.0.580 or today's build looks like a good one.

After that, the next step is the machine specs and graphics card info to see if anything is up there.

There was a problem with a specific OpenGL 3 sprite codepath that would only send alpha if a color attribute was present, and alpha wasn't properly multiplying the sprite's color. This is fixed in 11.0.581.

I'll guess my copy sphere solution will have to do..
thanks though