In the past I've had problems with opening a folder of pictures in Finder, where I do like Select All, Cmd-O, and they all open in Preview. MOST of the time they'd all open in one window, but occasionally, preview would just get a wild hair and decide to open one or two of them in a separate window.
Most of the time I could just quit Preview and repeat the Cmd-O and it wold work. Sometimes I'd have to do that several times. On rare occasion it just didn't want to play ball with me and I'd give up the option of just using my up/down arrows to rapidly switch between images.
But
NOW Sierra has kicked it up a notch. Opening a folder with any significant number of photos is at extremely high risk of opening several of them in another window. Again, for no apparent reason. Quitting and relaunching Preview is only very rarely effective at getting it to open them in the same window.
So I go off to google to see if this is just me. Nope. Several are calling it a "preview bug". A few mention I can change this behavior in preferences. Oh, I hadn't even looked at that! Okay, perfect,
(o) Open all files in one window
(o) Open groups of files in the same window
(o) Open each file in its own window
Awesome, this looks like what it might have been doing. Make sure One Window is selected. Wow, that appears to have worked. Wait, I'm missing some. No, there's not another window open, just that one. Why didn't it open all of them? Repeat, repeat. No, this is consistently wrong.
Look closer... okay, it's opening pictures in the order 1, 2, 3, 5, 6, 8, 9, 10, 11, 12, 7, 4
Normally Preview (or anything else concerning opening multiple documents) opens them in the order you select them in Finder, or always sorts them alphabetically. (in this case, that means the same thing, 1 through 12,
in that order) Cmd-O to select all selects from top to bottom usually. So.... NO CLUE what it's using for the sort order with these. And it's happening with many folders of pictures, all taken from my digital camera at the same time per folder. Maybe it's opening "one group", and then opening "another group" after that, like the 7 and 4 are in group 2 so they get opened separately but in the same window?
So.... is there any "method to the madness" here? Is there some way I can get Preview to function the way it used to say, back in 10.6 or so, when Cmd-O opened every picture I selected in the same window, by order of filename?
Oh, also, making matters slightly worse... I occasionally open two different groups of photos in separate windows. NOW things really get annoying. If I have "one window" selected,
it really means one window, as when I open the second folder of images, it opens them
in the same window. Arg!
-- update --
I finally started hauling out bigger guns. Duplicating files, moving them to other storage and back to reset inodes, I even wrote a script to change ALL file dates to incrementally larger values to insure dates were in order. Nothing. I had a single folder of 8 images, that REFUSED to cooperate, either opening in two separate windows (with 3 and 4 in their own second window) or in order 1,2,5,6,7,8,3,4, despite whatever I did to the files or the preferences of Preview. Clearly it saw something in 3 and 4 that it demanded to group separately.
Finally came across a fix. "It's GOT to be getting its sort order out of the metadata since I've tried literally everything else." Flushed metatata.
instantly all images opened in alphabetical order, in the same window.
https://imageoptim.com/macI occasionally rotate images, and that is probably being stored in metadata rather than being resampled, so it may not end up being a perfect solution. (and no, 3 and 4 were not rotated, I have NO idea why it insisted on segregating them)
