Yes, I've done this (others have, too).
I did it "the old fashioned way":
I installed HS onto an EXTERNAL platter-based hard drive pre-initialized in HFS+.
The install went through "as HFS+", and all subsequent upgrades HAVE NOT "converted" it.
The drive remains at HFS+.
I was even able to "clone that over" to an SSD, and it ran High Sierra fine in HFS+, as well.
How you accomplish this, depends on "where you are right now", and whether or not you have an EXTERNAL drive available.
It's also possible to use the terminal utility to FORCE the installer to install as HFS+, without converting an internal SSD to APFS beforehand.
Here's a page that discusses the issue:
https://apple.stackexchange.com/que...ent-conversion-to-apfs-on-high-sierra-install
In short, I think you have to do this:
- Have the "target drive" pre-initialized to HFS+ (Mac OS extended with journaling enabled, GUID partition format). This -might- work to "upgrade" an existing OS install as well, I just don't know the answer to that.
- Have the High Sierra installer located in your Applications folder (I would also keep a copy of it somewhere else, in case you need to access it again).
- Run the following command in Terminal:
/Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/startosinstall --converttoapfs NO
- Agree to the license agreement, and go on from there.
DISCLAIMER:
I HAVE NOT tried the above procedure yet myself (again, I did it differently as I outlined earlier).
I believe others have done this and it worked out fine.
