Using the sharpen/masking button and holding the option key...

Though you can change the key commands for screenshots on mac, Phtoshop does nto let go to allow you to do that.

You can also use grab to take a timed screen shot.

I personally prefer Jeff's Method having the images resolution to match the original, but mentioning incase that helps anyone.

There are many "edge finding" methods in Photoshop.

As previously suggested, Filter menu > Filter gallery > Stylize > Glowing Edges is one such method (not for CMYK files). This tends to round off sharp corners.

Another is Filter menu > Stylize > Find edges which can sometimes do a better job of preserving sharp corners (you may/would need to invert the result).

Then there are a whole host of other methods, using "Difference of Gaussians" or "Difference of Median" or similar approaches, or using a matrix of values in the Filter menu > Other > Custom filter. I'll try to dig up and post a link to this last batch of methods as I made some actions many years ago exploring these alternative methods.

brianm51947426  schrieb I am trying to figure out a way to save a picture when using the sharpen/masking button and holding the Option key - it turns the picture black and white - like an outline of what you're sharpening.  Is there a way to save this as a photo?  I just like the looks of it.

As far as I konw there's no way to save the picture at this point.

The only thing you can try is to create a screenshot. But I don't know if it's possible at this point.