Depending on how new you are to the forum, there are different photo posting options.
Everybody can post images that are hosted on other websites, including sites like flickr and even facebook, if the facebook post has permissions that are open to the public. All you have to do is post the link to the image on flickr in the text of your post, and it will automatically be parsed as an image. So, for example, if I paste a link like this into my post:
If you're just posting a link from your own website, click the PHOTO icon at the far right of the tool bar above the posting window, and it will give you a field to paste the link into, and you can embed the image that way.
If you've been a member for a while and know that you're not a spammer or scumbag trying to hijack my site, I'll upgrade your user level from "subscriber" or "member" to "trusted member".
Once that's done, you can upload your images directly to this site and post them here.
You can upload JPGs, PNGs, or GIFs, but they'll all be transformed into JPGs at no larger than 2000 pixels on a side. Still a decent size, but manageable for our servers. You can upload up to 5 images per post.
Still working on making this method a little more user friendly... more details to come.
For the time being, posting photos on these forums is disabled, as I'm switching to new forum software. So, hold tight. If you would like to post something, just let me know, and I'll move this up my priority list.