When linking to images in Dropbox, by default a link is created to a web page with an image on that page.
To directly link to the image itself:
- Add the image to Dropbox
- Right click image -> Share Dropbox Link
- This will copy an image URL to your clipboard. The end of the URL will be "...?dl=0"
- Simply change the last 0 to a 1 so that it now reads "...?dl=1".
For example, this link:
Will now be: