Differences in size betwen an image visualized on photoshop and on finder?

[Alba5C9E]

Hello,
I've been working on some banners and I've realized that when I'm working on them in photoshop the proportions are smaller than when I open it in finder or in the web browser?? It's annoying mostly because they look worse in the "correct" size, obviously. Does anybody know why this happens?? It's somehting related to the screen or it's something wrong? :S

This (on the left as seen on photoshop, on the right in finder):

Thanks!!!

[D Fosse · Accepted solution]

It's because you have a retina screen. Photoshop is the one that displays it correctly.

Consumer-oriented viewers/browsers scale up 2x linear dimensions when they detect a high-resolution screen. They do this so that everything will display at roughly the same screen size as it would on a traditional screen.

This is the industry-standard workaround to ensure the same material can be used regardless of the screen technology the user happens to have.

In Photoshop, 100% has nothing to do with size. It means one image pixel is represented by exactly one physical screen pixel. To replicate the browser behavior in Photoshop, View > 200 %. This maps one image pixel to four screen pixels.