Today Google+ made an update and changed all the sizes for your profile images. The new art required is broken into three definitions and sizes:
1. Profile picture — larger than before with a minimum upload of 250 pixels X 250 pixels and a recommended format of jpg or png.
2. Cover photo — a large panoramic style photo that goes behind and extends past your profile picture on the right side. This new format ties the images together nicely, making a lot of impact. It can also create a beautiful branded image for you and/or your company. The size is 940 pixels X 180 pixels and the recommended format is either jpg or png.
3. Scrapbook photos — these can either be five individual photos or one large photo cropped into individual squares that are 110 pixels X 110 pixels. The recommended format is jpg, png, or gif.
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So, you have the option of using one large cover photo, five individual photos or five coordinated photos that make one long image (see image above). The cover photo is deeper and extends further across than the scrapbook configuration with the five square photos.
Once you have chosen your photos, go to the profile and click “Edit Profile” to edit your photos. Alternatively, if you mouse over the cover photos, it asks if you would like to “Change Cover Photo.” There are two small graphics over the scrapbook photos where you can choose a template for the large cover photo or the five scrapbook photos.
You can preview your work before making it public, which is always a good thing. Enjoy!
More information can be found on Google.