Quick look scaling in Mojave

You need to press "Command + O" to switch to "Actual Size".

alekseyfromsan francisco wrote:

I am sorry about misunderstanding. I actually meant Quick Look, not Preview application. I corrected the question details.

And yes, command 0, -, + work in quick look too. Thanks for the tip.

In Mojave they added edit capabilities to Quick Look, which is nice, but now "option" button handles changes in rotation direction. I am not sure if this is an overlap or they removed the former functionality completely. It was convenient though - I could use just one button when going over my gallery to identify images with focus issues and delete them. command 0 is better than nothing, but it does not go in the other direction.

Yes your "Quick Look" will take some getting used to.

You can always submit your user experience for improvements to the interface—

Apple Feedback http://www.apple.com/feedback

I checked High Sierra and you are correct. If you open an image with Quick Look using the space bar, then press option, it would switch to actual size.

Try "option + space bar".

Of course? You'd be surprised. 😎

alekseyfromsan francisco wrote:

I am very pleased with new features of Mojave, but I am disappointed to find out that I can no longer switch to 100% scale while previewing images in macOS Mojave. Previously when I open an image in Preview, I could click "option" keyboard button and quickly switch to 100% resolution. Now this does not work. Is it a bug or they deliberately removed this useful feature?

You still have the option for defining scale on PDF's and images— Preview>Preferences>Images/PDF

and as dialabrain suggest above the keyboard short cut works like it always has

command 0 (actual)

command - (smaller)

command + (larger)

https://support.apple.com/guide/preview/welcome/mac

How to edit images and mark up PDFs with Preview on your Mac - Apple Support