To make Photoshop CS6 behave like a non-retina application, select the Photoshop application in the Finder and choose File > Get Info. If you have a Retina display, under General, there will be an option to “Open in Low Resolution”. This probably isn’t something that most people will do, but I used it when demonstrating Photoshop last week.
You will only have Retina support if you have downloaded the update to Photoshop CS6. Here’s how to get the update:
1. In Photoshop, choose Help > Updates.
2. The Adobe Application Manager will launch. Select Adobe Photoshop CS6 and choose Update.
How to confirm that the Update worked
1. In Photoshop, choose Help > About Photoshop (Win), or Photoshop > About Photoshop (Mac)
2. For Mac perpetual customers, the version at the top should be Version: 13.0.3
3. For Win/Mac Creative Cloud members, the version at the top should be Version: 13.1.1