I’ve recently loaded a 5.2 project in 5.3 that I’m working on for a cinematic shot and I’m getting this weird issue.
The mesh is in the shape of a logo that’s extruded as a light beam and as a result has several layers when looking at it from the side, the material is using a Fresnel node and is translucent and emissive. I’ve not changed anything in the material. In UE5.2 it works fine (second image) but as you can see from the first image the light seems to change colour or goes completely black in places when viewed from specific angles.
I’ve only just noticed this in the sequences and have already done a load of work on the landscape in UE5.3.
Does anyone know why this is happening or any settings that I need to adjust to fix it… as I’ve literally no idea what’s happened.
It’s a total bummer as now I’m going to have to do a composite of two different renders, one from each engine.
So, after a little bit of playing around I managed to fix this issue, it turns out that I needed to clamp part of my signal flow into the emissive. I basically had a Fresnel node that was being used for my translucency opacity but it was also being sent into my emissive chain of nodes, doing so gives a higher contrast and a more detailed effect. I found though that if the value goes below 0 when going into the emissive chain of nodes then it has this effect where colours are inverted or it goes black in places. I’m still not 100% sure why this wasn’t happening in 5.2, maybe the value was being clamped in one of the nodes or the fresnel chain wasn’t outputting below 0. Something’s definitely changed with 5.3 that effects the overall signal values as I didn’t change anything. Anyway, after clamping the signal to a min of ‘0’ going into the emissive chain of nodes from the fresnel chain it fixed the issue and the effect looks pretty much identical to before.
Maybe this might help someone else that’s having this issue.
