From a marketing point of view, you should keep the uploader as simple as possible.
If you have already created a page and added the
[imagepress-add] shortcode, then head over to ImagePress Settings -> Upload and set it up accordingly.
If you want to keep a close eye on your disk space, set image quality between
90. Depending on what images your users are going to upload, go with 8Mb or 16Mb (
In most cases you won’t need secondary uploads, but if you need them, know that all secondary images will be attached to the image post type and displayed in a sequence, below the content.