Custom Convolution Bloom Kernel UE5 Issues

Development Asset Creation
1

I’m having issues with all bloom kernel textures other than the default kernel that comes with the engine. The image appears extremely blurred regardless of the post process volume settings.

I tried a kernel pack that worked perfectly in UE4 and tested it with UE5.1, 5.3 and 5.5 and it has the same blur issue on all the UE5 versions. The default kernel appears to have an alpha channel now which it didn’t have in the UE4 version of the same image file. However even adding an alpha image to either custom made kernels or editing the ones in the pack to have it does not solve the issue for them.

Has anyone managed to make any custom bloom kernels work in UE5? The only videos I’ve seen with it working are in UE4 or use the default kernel.

Cheers,
Chris

2

I messed with it today and got it to work but it seems like a bit of hassle to make it look good. I followed the instructions on epic’s article for it.

Main takeaways are:

Export your image as an .exr file

Go into the image texture, and set “Mip Gen Settings” to “NoMipmaps” and to check “Never Stream”

And from what little I’ve practiced on, I think you need to have a really small texture, like one to two pixels in the middle of a 2048x2048 image, otherwise the blur gets massive. The article mentions that extreme blurring can become an issue.

This should at least get you started, cheers.

https://dev.epicgames.com/documentation/unreal-engine/bloom-in-unreal-engine?application_version=5.3