Sometimes haze is caused by too high a setting on variations that feature Blur. I like it in some 3D flames
Another cause is inaccurate placement of the triangles. Being off the "highwire" even a smidgen will make things fuzzy. Variations have specific areas in fractal space where the highest concentration of pixels live, just part of the math of combining functions.
Also, there are some variations with built-in artifact that's sometimes correctable by using different gradients or changing weights or XAOS. It takes lots of practice to get things totally clean, so don't get discouraged!
I'm still struggling with this.
I'm trying to get crisp flames, which I tend to get is like this dots and haze. I had to put a tiny attachment.
I can't for this life of me figure out how to clean it up.