Employees photos equal size


I’m having a problem with the photos of employees found here under the section “artists”:


the photos are exactly the same size (500x500) but get resized in different measures when displayed. Could you help me with this?



None of those images are 500x500. Please check them again.
This is what I see 552 × 548 and 383 × 432.

this is very strange… I’ve checked both images in photoshop and both are 500x500 72dpi. also on the wordpress media section I see the same, as shown below. Do you have any idea about what is going on?



I know see one of them at 500x500.

I think that Photon or whatever that thing from Jetpack is called is causing the issue.
The image with issues has this link inside the src: http://i0.wp.com/www.gravitationalattraction.com/wp-content/uploads/2014/10/Artist-Yancy-Way.jpg?w=640
When it should have this one instead:

I changed it in Chrome debugger in your website and it looks alright.