theymos restricted them due to abuse.
https://bitcointalk.org/index.php?topic=1172918.0You could ask a higher rank member to quote your post and then the image will show.
Forgetting that you can wait until you're Junior Member and you will be able to post images.
How many posts required to become junior member?
8 More activity post. Though you need to have 8 eligible activity. Potential activity is 1 per day, updated every two weeks i believe. Basically after the next activity update, you'll be able to go up to 42 activity i think, up from 28.