(Old Editor)

You can change an image's resolution when you upload it to thewebconsole. 

Resize the image to be either "small", "medium", "large", or specify a size in pixels when you upload to the image manager. For a general indication of size:

1. Small is typically used for thumbnails
2. Medium for most general images
3. Large for when you want to show a bigger version of your image in a popup

(New Editor)

Your image resolution is always controlled by you prior to upload.

Your image sizes can be adjusted by hovering over your image within the website editor, clicking on the image box in the top right of the image, then you can resize, crop, flip and turn your image as you wish.

Please note for SEO and correct display purposes, images can only be resized using aspect ratio, this also means once an image has reached the maximum width of the column it is in it will not be able to be made any taller as aspect ratio will try to make it wider - to achieve this you would first need to crop your image width to be able to make it taller and vice versa.