I see a few topics about image sizes and I'm not sure I'm using the optimal settings in Gallery. My sizes might be carried over from older upgraded versions. If you run Gallery, what are you using for your sizes? This is what I have currently:

 

There is also a setting for 

However, mine are rectangle and probably because of my low thumbnail size.

(1) I'm not a fan of square thumbnails personally, but to each their own.

(2) You only have two sizes available in 4.3, and the defaults are 1600x1200 for large images and 600x600 for small (note that this does not make the image square - it means the width and the height cannot exceed 600 so the image will be resized to fit within those constraints while retaining its width/height ratio, unless you enable square thumbnails)

Got it, I haven't updated this site yet to 4.3. Thanks for the information!

10 hours ago, bfarber said:

(2) You only have two sizes available in 4.3, and the defaults are 1600x1200 for large images and 600x600 for small (note that this does not make the image square - it means the width and the height cannot exceed 600 so the image will be resized to fit within those constraints while retaining its width/height ratio, unless you enable square thumbnails)

Do we have an option to customize these sizes before rebuilding the gallery or it will be done automatically and again after that if we change the settings? Question not only for you, but for anyone that have upgraded to 4.3 :)

When you change the settings, you will be asked/prompted at that point in time if you want to rebuild your images or not.

1 hour ago, bfarber said:

When you change the settings, you will be asked/prompted at that point in time if you want to rebuild your images or not.

Thats fine. But the initial rebuild during upgrade is made with the settings you mentioned or the old settings are preserved with simply removing thumbnail and medium?

We do not adjust your existing settings during upgrade.