The reason why there's bloom in real life is because of dust or refraction of particles in the air.
Surprisingly, this idea failed completely in every way when I tried it in cylces using a simple volume/add shader on a cube. I made a simple light that I want to have a bloom effect. Then I added a volume cube with both low and high density, and no bloom happened even though the volume itself clearly obscured other scene objects.
I truly cannot even begin to fathom why this didn't work. What's going on??
Okay, I'm extremely confused. I turned the emission strength up to 10,000, and I'm dealing with objects only less than a meter across, and it had no effect!! What the hell is going on? Why would turning the emission strength up have zero effect on other objects??????
You need to learn how to use volumetrics and bloom first, as well as be aware of its pitfalls, which are many. One of the things with Blender is that first things need to go wrong before you get the hang of them. I can link a couple of tutorials that focus on or use volumetrics if you want to watch them.
Hi Sid - While you may be correct about volumetrics contributing to light bloom, it's not an optimal way to achieve the effect. Volumetrics are very expensive in terms of rendering computation and should only be used when absolutely necessary. Bloom is far more easily achieved with post-processing, like the glare node.
Often I see students thinking computer graphics are a perfect simulation of reality. Thus if we set up a scene exactly how it is in reality, it should just work. But reality is far too complex to comprehensively simulate, and thus CG software is an approximation. While this may be disappointing, the good news is that approximations are good enough in 2025 to achieve very believable results!
Without screenshots it's hard to tell, but if emissions not showing usually is either you're using eevee render engine or you are in material preview instead of render(z->render) shading mode.
