Rua / Whitepaw &🏳️🌈🇳🇱After recapping a dead Macintosh SE/30 at the #HomeComputerMuseum, we switched it on to see if our work had made any improvements. We were greeted with this startup screen.
Scott Small 🇨🇦@ruawhitepaw Wow, is that startup screen archived anywhere? I’d like to use it with my SE 😁
@smallsco It's on that computer somewhere I assume, but I know next to nothing about Macs, old nor new. Any idea where a startup screen would be set/stored within the system?
@ruawhitepaw Yeah, there will be a file located under the System Folder named “StartupScreen”. It’s a PICT file with the image data stored in the resource fork, so it will need to be converted to BinHex or MacBinary before it can be uploaded to the net in order not to destroy the resource fork (you can use a file compression program called Stuffit to do this).
https://apple.fandom.com/wiki/Mac_OS_startup_screen
https://www.macintoshrepository.org/software_search.php?s=stuffit&sid=&p=1
Mac OS startup screen
The Mac OS startup screen is the image displayed by a Macintosh after the Happy Mac icon that indicates bootable media with a proper System Folder has been found. The image is displayed by the operating system while it is loading from the startup disk. From the original Macintosh System Software through System 7.5, this was a white rectangle with a black border displaying the words "Welcome to Macintosh". This was updated during the Macintosh System rebranding with Mac OS 7.5.1, such that 7.5.3
@smallsco @Silver_Tusk
I was able to extract it and convert it to a PNG. I have the original file too, but Mastodon doesn't let me upload that.
I was able to extract it and convert it to a PNG. I have the original file too, but Mastodon doesn't let me upload that.
fenarinarsa 
From what I could see inside the file, it's a raw image with no header containing metadata. 512x342 resolution, 1 bit per pixel, 21888 bytes exactly.
@ruawhitepaw Oh strange, what System version? It changed after that, on System 7.5 at least it was a PICT file in the resource fork of a file to change with ResEdit, if I remember well.