How to change the parameters of a Blendable Material from a PostProcessVolume?

I have a 0.0 to 1.0 GAMMA setting that I can set in a menu, and a “blendable” material set up as described here.

I have placed the blendable material into the blendables array of my post process volume.

I have a blueprint function that can successfully get that material.

I assumed that I need to use dynamic material instances to modify the parameter within that material and have tried to do so, but no change is visible.

I have tried using a parameter collection, with the same lack of effect.

I am unsure of how to proceed. Is there any existing examples of how to do this from start to finish?
Or even any clues as to what I am missing?

The only way to do this I have had success with is through a collection. Can you show the nodes you used for this?

The only way to do this I have had success with is through a collection. Can you show the nodes you used for this?

It is not currently connected but this is it:

39438-paramcollect.jpg

And here is the Material:

39439-gammamat.jpg

I was looking at the example [here][3], which does not mention a need to spawn or initialize the collection.

If I need to, I have been unable to find the related node.

I think this might help u

Sorry, i don’t know why but this topic has all wigged out on me. It double posted the answer and i get no notifications till now.

You don’t need to spawn or initialize anything, does your example above not work?

At some point in 4.6 (i think) the MID was broken and would not update. If this works now then this would be a good solution except for the fact that you would be required to do this per level transition if your post processing is controlled in each level. Using a collection guarantees it will be set for any postprocess component with the blendable plugged in.

This worked for me. Quick and easy!