I wanted to copy subset of photos into a new folder but also keep the originals in original folder. Can I undo this?

I'm thinking that you mean albums rather than folders. In the Photos app, folders contain albums; albums have pictures. In fact, albums really just have lists of pictures, and so a "picture" can be in several albums--on several lists. You can delete a picture from an album (really you're deleting the picture from a list), and the lists of pictures in other albums are not affected.

So you can select a group of pictures in an album and go to "File>New Album With Selection" and get a new album. All the pictures remain in the original album--they're still on its list. And you can manipulate pictures in this new album. But, again, deleting a picture from this new album doesn't delete it from the other albums it may be in.

If you want to delete a picture from the Library, from all the albums, then you can use command-delete. That removes the picture from the active Library and puts in the "Recently Deleted" album where it stays for 30 days and then disappears forever.

I use keywords to help me organize and "weed out" pictures. Keywords are a very powerful feature of Photos. With Keyword Manager you can set up shortcuts that let you use a single character to mark pictures. This article talks about keywords:

Find photos by keyword in Photos on Mac - Apple Palaikymas (LT)

"It says "Delete 2 Photos" -- is this different in German?"

It will depend where you are looking, Richard.

When I am looking in a standard album, created by myself, where photos can be removed, I am seeing the "remove from album", but not in "All Photos" or other predefined albums, or smart albums, where we cannot remove photos from the album, only delete them from the library.

• In "All Photos" or in a smart album or any predefined album in Photos, where we can only delete and not remove from the album, I am seeing this in the "Image" menu, when I select a photo - only the "delete" command.

The contextual menu is showing the same commands, but without the shortcuts.

• In any standard album, created by myself, the Image menu is showing me both commands, the "Delete ⌘⌫ " and the "Remove from album ⌫".

And in the contextual menu the keyboard shortcuts are also missing.

That's a better way of talking about the process. Of course, the source of confusion is that ⌫ button that says "delete" on it.

Hold it-- I just looked at the menu:

It says "Delete 2 Photos" -- is this different in German?

And it doesn't list the shortcut, ⌫ !

If you're not emailing, then you should select the pictures you want and then choose File>Export>Export nn Photos, and specify a folder to put them in. You will be shown a dialog in which you can choose how you want the pictures named and what metadata you want included:

You can also choose File>Export>Export Unmodified Originals, but you don't get any choices about what's included. The picture files will be exactly what was originally imported.

"But, again, deleting a picture from this new album doesn't delete it from the other albums it may be in. "

I would rephrase this slightly, Richard, as "remove from album" or "delete" are different commands, and say

"But, again, removing a picture from this new album doesn't delete it from the library or remove it from the other albums it may be in. "

Photos has two command for photos in album , when you ctrl-click a photo or select it or use the "Image" menu: "Image > Remove one Photo from album ⌫ " or "Image > delete one photo ⌘⌫ "

Lynne needs to use the "remove" command and not the "delete" command.

Ahh-- I've been working in a Smart Album and, of course, you can't "remove" a picture from a Smart Album, since what's in it and not in it is already specified. "Remove" is the word used for removing a picture from an album, even though you use the "delete" key. You'd think I would have noticed that, before....

Thanks!

I'm from the age where one sent film to be developed!

I'm with you. I'm working on slides and prints that have been scanned. No metadata, no GPS, no dates.

Probably the easiest way to send pictures from you Photos Library by email is to use “Share.” 

First, select the pictures you want. When you see the thumbnails in an Album, you click on the first one. Then, if you want several in a row, you Shift-click on the last one, and all the pictures in between will be selected. (Alternatively, you can click on the first one and then command-click on each additional picture, selecting them without getting the ones in between.)

 Once they’re selected, control-click (or right click) on any one of them, and select Share>Mail from the menu. A new email will pop up with your pictures in it. If you like, you can choose a different size instead of Actual Size. 

There are other ways if you want to explore...

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