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Right yes, my bad i did mean what size in KB

Well, having a smaller image size in terms of width and height, like 800x480 for example, essentially does result in not having a large in terms of file size image, so that should not be a problem. If publishing photos and you want to have a higher- resolution version, you just link the smaller image to a high-res version, so that when it is clicked om it will open the larger version in a new window.

Awesome thanks for the advice

To optimize the loading of your images on the web try to keep them under 600 ko and all will be fine.