I want to edit a very decorative cc ceiling lamp to not fade when you zoom in the way most ceiling lights do. I know it's possible, because some of them don't - like the store Starlight Satellite Chandelier, for example. I have a fixed package of that light I can look at in S3PE, but I have no idea what the relevant difference between them is. I was really hoping for a simple "fade yes/no" kind of thing I tried changing the script class, and also deleting the rig (the store lamp doesn't have one), but neither did anything. I'm stuck! Please tell me if you know where to look.

Comparing the two was a good instinct!
The one discrepancy I can spy between that light and one of the base game ones is the FadeType entry on the MODL resource.
You can edit this by selecting the resource, pressing the Grid button, and going through the dropdowns for ChunkEntries > [0] ChunkEntries > RCOLBlock. The FadeType for the store light is 0x00000000 - which sounds promising.

I actually have a Sims4Studio thread to thank for the hint to look there- I figured EAxis probably hadn't changed their formula that much.

+ Additional recommendation for the No Fade Camera mod- not 100% sure if it covers ceiling lights but I've relied on this for years now.

It worked perfectly! Thank you! Now I can see all the hanging crystals on this chandelier in gameplay

I never thought there would be anything like this anywhere but the OBJD. Now I know to be more thorough with the expand all on everything I can find! And I guess I shouldn't have ignored all the TS2/TS4 results I found, for once...

(I thought about that mod, but I wasn't sure I wanted it for all lights, let alone for trees & sims too - but thank you for the recommendation!)