UI Scaling On UHD 4K Monitor

I had this same issue and here is how I resolved it (Windows 10, works for almost any program that has this issue):

go to the folder in which your bridge.exe is located and right click

select properties

select the compatability tab

click "Change high DPI settings"

check the box "override high DPI scaling behavior

in the dropdown below, select "system (enhanced)"

Next time you open the program it should be in a more normal size.  Hope this helps someone!

MiaKai  wrote After setting up a new computer using an ASUS PB287Q - 28" - 3840 x 2160 Monitor, my images no longer open as their actual size...This image was created as follows: 358 x 327 pixels

Your ASUS PB287Q monitor has a resolution of 157 pixels per inch, so your 358 x 327 pixel image at 1:1 magnification (what the Photoshop View menu calls "100%") works out to about 2 1/4 inches by 2 inches. If that's how the graphic measures when you hold up a ruler to the screen, it's being displayed correctly at 1:1 size on that monitor.

One workaround you might try is that Photoshop has a command for 200% magnification, and you can customize the shortcut using Edit > Keyboard Shortcuts. If you customize the shortcut by defining Ctrl+1 as the shortcut for View > 200%, does that make the graphic easier to see and edit? If so, you can now use Ctrl+1 as a quick shortcut to zoom instantly to a more readable magnification on that display.

Thanks to everyone who worked at getting my head around to all of this.  I'm not really sure why I'm going to do at this point.  I just know that I can't keep my hobby in motion with things as they are.  Granted I'm not the type of professional user as was mentioned in one of the comments, but I pay for Photoshop just like everyone else.  I wasn't thinking outside the box when having my computer built.  I was simply thinking, damn, this is going to be awesome!  And, it is for World of Warcraft. 

It is the same size as it always was - it just displays smaller on a high density display, due to the higher pixel density. If you connect a standard 1920 x 1080 display, it's back to what you're used to.

This is a big issue at this particular point in time, because these two display technologies (that are basically incompatible) exist side by side. The only way to deal with it is by workarounds. In time we'll all have high density displays, and the problem no longer exists.

The common workaround currently used, is to scale up when a high density display is detected. Almost all non-critical applications - web browsers, photo viewers - do this. But Photoshop can't do that - it has to display accurately, and the scaling strategy is not accurate. Also, don't forget that this concerns a very small part of the Photoshop user base. For photographers, print designers, prepress, medical and forensic workers, and many others, the higher display resolution is all upside and no downside.

https://groups.io/g/apothecarium/files/Samples/Christmas%202016.gif

The above image was created with the following information:

358 x 327 pixels

72 resolution

1920 x 1200 monitor

I didn't use large file sizes because things never needed to be printed or processed otherwise.  When in Photoshop, I didn't have to zoom in or zoom out in order for things to look right, and even doing that now, there is no amount of zooming that makes it look okay. What I created and how it looked open in Photoshop, looked the same way to the members in my graphics group. In trying to duplicate the equivalent on this new monitor, it seems the only way around this is to start every project over from scratch. That being said, the file size more than doubles.

When you press CTRL+0 what do you get?  Have you tried it?