I have an asset with lights attached to sockets on the bones.
It is possible to expose those light parameters so i can edit them without having to recompile the BP?
and can these parameters be accessed by matinee so i can tweak values on a shot by shot basis of a cinematic sequence?
There is Expose to Matinee option for variables in blueprints. If you create a variable for the light intensity and then expose it to Matinee you should be able to have access to it. I havent tried this myself though.
thank you for the reply- i assume this is done in the graph section, rather than on the light components?
thank you- im very new to blueprints 
how do i link the variable to my light
thank you so much for this - its exactly at my level!
however, i cant add a tick event as it does not seem available
i have most likely set up my initial BP wrong.
I had dragged my asset into the world, scrolled to the bottom of its parameters and clicked the “create skeletal mesh actor blueprint”
in here i have added my lights under the component tab
and exposed the parameter in the graph- which does appear as a slider at the game level but has no effect (i guess caus there is no event tick!)
Yeah. Create an exposed float variable to set the light’s intensity. You’ll need to set it every tick i think. That is, Event Tick > Set Intensity.
Make sure you are doing this in the Event Graph of your BP, not Construction Script. Construction script executes only when the BP is placed in a level so you cant use EventTick there.
Here is a screenshot of how it should look in the event graph of your BP:
thank you for your patience 
i got there in the end
part of the problem was the light changes are not visible in matinee
i only see the intensity change when i hit play (in the engine)
playing via matinee still shows no change, however if i export a movie it does!
a minor, but frustrating issue!
That is strange. It should work when you hit play. I’ll have to try it myself in order to see if there is a workaround or if it is broken, so that we can report it as a bug if need be.
If you change the lights intensity (either on the assets parameters or via a matinee key frame) do you see a change
I font. but assumed it needs played to see a result.
Hitting play or loop (inside matinee) I don’t see any change.
If I close matinee and play my level it works. Equally on export matinee I see the changes.
My matinee is set to load on event play yes.
Ideally I want full control over lights intensity, colour and position. Like a controlled light rig that follows my chr
Well i’ve taken a look and it does change when i play in the editor. Is your matinee set to Play on Level Load?
Oh, that is expected behavior then. Since we are setting the intensity in event graph it affects can be seen only during play(or when simulated.) If you want to make a light that follows the player though i would use a Timeline in the character BP instead of Matinee.
so even hitting play inside matinee you still wouldn’t expect to see any changes?
and my lights are all attached via the BP, only using matinee to change intensity, colour, slight position via matinee
No, you wont be able to see any change like that. If it was a light component inside the level then it would work, but not when you control a BP variable with Matinee like this.
As i said, since the lights are already in the BP give Timeline some thought. It will give you more flexibility in the long run.
