Expand "Additional Options" below the text box. You need to shrink your awesome photos down to <512KB in size first.
Allowed file types: gif, jpg, mpg, pdf, png, txt, xls
Maximum attachment size allowed: 512 KB, per post: 8
As attachment, reader needs to click on the thumbnail to see the enlarged size, and only users logged in can see the attachments.
By default, all attachments appear below your main post, which may not be what you want. Here is a workaround if you want to embed the image: you can use this thread as your attachment dump, i.e. uploading your attachments here. You just need to click on the thumbnail to get the enlarged image to display, then right click to get the image URL (or image address) . Save that URL, and then go to your desired thread to embed the image in your photo report.
P.S. Here is the example code that I did for that embedding test post.
Don't abuse it, kids! Supertopo shut down because they hosted photos.