This will help explain the right guidelines for uploading photos that can attract your audience.
The product image size is: 600 X 400px
Meaning its aspect ratio is 0.66. It is suggested to use images with a 0.66 aspect ratio to avoid cropping or whatever.
Suggestions to use product images in action or out of action, white or black background.
Here is an awesome tool to help you resize images. Click here.
The company's page background image.
The image size for a company page is: 1480 X 500 Px
Meaning its aspect ratio is 0.33. It is suggested to use images with a 0.33 aspect ratio to avoid cropping or whatever.