Did you ever make a mistake? It happened to me...
Even then, you have no proof it worked correctly before the update, so these are just wild allegations at this point
I'm not sure where you are going with have I ever made a mistake and wild allegations....
Of course I have made mistakes....I bought $#!+ cameras before I found this site LOL. I updated a perfectly working camera once and bricked it. I have blown up BI and had to restart it from scratch. The list goes on just within this field LOL.
My intent was I have at least six of the 5442 cameras, from when they first came out to one purchased within the last 6 months or so - all are running different firmware and I cannot tell a difference in picture quality from the camera running the first version of the firmware to the camera with the most recent version. So either you hadn't dialed in the cameras to your field of view so there were setup differences between the two that resulted in one having what you say was significant enough differences in picture quality that the updated firmware changed or you got a dud. But I am learning towards not being dialed in. I have seen two identical cameras each looking at the same thing and their setup be completely different after dialing them in.
You are the one that said your camera was working OK until you did the firmware update, not me, so with you being a NOOB to this site, I was simply pointing out a lesson learned that many of us have experienced with firmware updates.
So have you tried my proposed solution or not LOL. My proposal will keep the camera on what you call the firmware that resulted in better picture quality.
Contrary to the term "factory reset", it doesn't reset it back to the firmware that the camera came from the factory with - if you updated the firmware, that is the firmware that will be on it after a factory reset....