I am not sure why the images are quite big in the Dawn Theme but do not worry. It is just an easy fix.
Note: You cannot just edit the the images since you will end up having a big space on the right side. The product info width has to be adjusted too.
- Go to your Online store > Themes > Actions > Edit code
- Go to Asset folder and open the section-main-product.css file.
- Find the code below
4. Change the max-width to 50%
5. Next, find the other code for the product info, see below
6. Change the padding-left to 5rem, max-width to 50%, then click SAVE
Let me know if you have questions. You can easily contact me at the "chat with us" (",)