Solution for changing Big Sur login wallpaper to custom.

Thank you, applewarm.

However, in my case, I have multiple users.

As such, I wouldn’t even want the login wallpaper to, necessarily, be the same as mine.

However, I now have a potential target for experimentation in providing a login-screen wallpaper.

(Incidentally. Within my /Library/Caches/Desktop Pictures, folder, I have UUID folders for each of my users, already.

In a sense, the question is simply Where is the appropriate place for the login-screen wallpaper? Or, what is it supposed to be called?)

Yep, that's it. I have both an admin account and a regular daily-use account; don't want to get rid of the admin account as that's my emergency backup if something goes seriously awry with the daily-use account; I can always get in and try to fix things if necessary (it's saved my hash a couple of times).

I also have a couple of computers which need to have the Guest account enabled.

I'll keep a watch out for a new version of OnyX; hopefully it will do the trick.

Thanks....

@Halliday, I'm a novice at going this deep into making system changes. I was just hoping that a simple renaming of a couple of files would allow the system to load a different desktop image. I guess I've exhausted the current options and will wait and see if someone develops a new approach.

The startup screen does not change in my scenario. I have 3 users and clicking on each user for login brings up the selected background. When the select user screen is up, the background is the default Big Sur picture (if you can call it a picture). Where is the system background picture located??

Does anybody actually understand why Apple did this? They really need to change it in an update or, at least, design an easy way to change it without having to go through 10 steps that don't work with Vault or Guest User. Google searching, I found multiple complaints about that image from months before Big Sur was released to the public. If Apple knew a lot of people find it "ugly" or "hideous" (other people's descriptions I found in google searches), why didn't Apple either change it to something that meets the aesthetic tastes of a larger number of people or, at least, design a way to give people a choice? Did they think the image appeals to a target demographic? I'm assuming it was just not something Apple thought really mattered to anybody. For me, that image has brought up long dead memories, including my Southern mother saying something is "as ugly as homemade sin" (hadn't thought of that in decades) and, more peculiar and perhaps more telling, memories of running Microsoft Vista with Parallels when Vista was new. I think it just reminds me of the ugly green Vista box and the Vista green and blue screen, but it's probably also the pointless complexity of actually putting up with Vista on Parallels or Boot Camp. It's actually kind of disturbing, and I can't for the life of me figure out why they didn't change it when it drew so many complaints in Beta.

I know this is the Big Sur section, but, the same exact steps work in Catalina! And although the Catalina stock login screen is not as obnoxious as Big Sur (what were they thinking!!!), I still prefer to have my chosen desktop background as the login screen.

Thank you applewarm for the tip.

Like you hildegard47, I am a long time Apple user/supporter and advocate. Only I go back to 1984 when my first rep firm employee was a Macintosh. Since then, I must have had just about every model Apple produced. And I agree, the last few years have just not been the same. Apple has lost sight of and contact with their user base. Maybe its the iPhones, maybe its the iPads, maybe its the Apple TV, or maybe I'm just getting old and fondly remember the days of Steve Jobs being at the helm.

But I'm also keeping the faith. Apple is a great company, with great products, and I'm sure that we're just in a cycle that's sadly being driven by deadlines rather than by innovation.

I too agree that Apple has lost its vision, their way or their innovation especially when Steve jobs left. For example the iPhone 12 they borrowed from the iPhone 4 design. I hope they can be innovative again or come out with a product that will wow people.

Then please choose an inclusive image that appeals to a broad spectrum of users, not one that looks like a middle aged man in loud golf shorts thinking he’s cool.

And thank you for the added security. I do appreciate that very very much.

Hey, hildegard47, I agree about the “loud” Big Sur image. (I suppose it’s an artists impression of the hills near the coast of Big Sur, or some such.)

However, Apple isn’t here.

We are but fellow users, like yourself.

That's a good point, but Apple should have a tick box in system preferences to sync the login screen with the desktop picture.

I've had my share just as you said of clients who have damaged their computers due to tinkering, thinking they can trash something out of the library folder or other things, Clean My Mac or virus programs, etc and the system is slow or the machine doesn't boot as expected.

To summarize, this method is easy to follow and won 't damage one's system if they follow it step by step.