Preview - Zoom in full screen?

You use OS X's built in zooming in feature

Go to system preferneces, then go to the universal access pane.

Next click the "seeing" tab and look for the options on zooming, and simply turn them on.

I discovered that if you're using a macbook that has the newer trackpads that support multi-touch, you can use the two-finger spread gesture to zoom in while in full screen mode in preview.

However, I can't figure out how to replicate this functionality with the keyboard or via menus, which means I can't use it on my older MBP... anybody know if this is even possible?

I don't know why they'd hide this functionality, but it's certainly not immediately obvious to me.

I can see that this thread is from all the way back from two-thousand and bloody nine, but this simple feature doesn't seem to be available in the latest mountain lion, ffs. 😡
Yeah, you can zoom using the screen zoom, "control+two fingered swipe" but the BIG problem with that is it zooms in on the resolution that the screen is already at, NOT on the possible/potential resolution of the actual image.
So it's always going to come out pixellated as all buggery in this way.
Windoze "image and fax viewer" allows us to do this perfectly.
Pick up your bloody act apple. You're supposed to be the go-to graphics machine. This is by no means a fix. So fix it! [please, pretty please with sugar on top. I'm not clever enough to rewrite and recode your applications]
I have no idea why the OP deleted their original posts. A bit weird. A perfectly legitimate complaint.