I did 16384*16384 as a test. I just slapped on heaps of huge images.
First, i started to resize the prokit, photoshop crashed. So i got rid of all the layers cept for the black mask, and resized it. It didn't crash
I then imported some 7MB images to photoshop. It then crashed.
Last time, i did the same thing and it didn't crash. i then saved it at maximum quality, which ended up crashing photoshop.
Last time i saved it again, saved it at medium quality. IT SAVED!
i then went to my folder i saved it in to see the damage. It ended up being 300MB.
Quite big ey?
So i thought i'm at this stage, i may aswell try lfs.
Went into lfs, and it said error, too much graphics or something.
And that's my story of the 16384*16384 image.
Never again. EVER