Preview - photos to stop at the last photo in the folder

By definition, Preview is a preview in larger size than the selected thumbnail. If you select more than one (up to nine), they will do what they can do to fit in the Preview window. That's how it is designed to work.

BTW, the default location for the Preview window is, well, stupid. I have found it much more effective to have it occupy one whole column. The Bridge's structure is to have three columns and as many rows as you can fit in each of those columns. You can move a Panel to a new location by grabbing the title area of the Panal and dragging it to the location of your preference. A Blue line will show where it will end up. If you see a full rectangle, it will go there. If you see a solid Blue line it will insert itself into that space. I like the Content Panel on the right (three thumbnails wide) and the Preview Panel in the middle. Then all other Panels are on the left side. Like everything in life YMMV.

Good luck!

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