Zoom.it is a great tool for viewing an online image. Zoom.it allows you enter the URL of an image on the Internet. Then you can zoom in and out or view the image in full screen. You can share the link to your image or copy the embed code to post the image on your blog or website.
Check out this image made with Zoom.it.
Putting an image on Zoom.it and then projecting it onto your SMART board would be a neat way to interact with the image. I personally like the ability to put the image onto a webpage.