Here are some points to consider:
when you export files from photoshp and test them out on your macbook , does the quality look The same as it was in photoshop before exporting ?
How about the file size? How much the file size is ? and the file dimentsions?
I keep seeing that the new Retina screen might have something to do with it.
It does indeed.
When you look at your files in other picture viewers and browsers, outside Photoshop, these applications pixel-double so that each image pixel is displayed as four screen pixels. They all do this when they detect a high-resolution display, it's hard-wired.
They do this so that everything will display at the same size on screen that people are used to from traditional displays. Otherwise they'd be flooded with user complaints. The higher the screen resolution, the smaller things get. This is just how it works. More screen pixels = smaller screen pixels.
Photoshop cannot do this. It has higher standards to live up to, and has to display accurately.
Other people without the retina screens are seeing it in the same way, unfortunately.
The quality is completely different. And when I import that exported file back into Photoshop, it looks terrible. But while I'm working in PS, everything looks great.
Well, what are the pixel dimensions? Open Image Size and check.
4288 x 2740 with 300 resolution