Could you add a "dim" or "black" the non-framed area option?

Firstly, thank you so much for Telescopius. As is, it’s an amazing website and people such as yourself who just give freely to the community are brilliant.

I have had a thought as to simple ways the framing experience could be improved as it’s surprising how much focusing on the target can make it appear different.

Would it be possible to add a toggle to dim or black out the background around the framed area? Only show the framed image and allow it to be rotated to landscape/portrait?

See imgur for my crappy example!

Standard framing: Imgur: The magic of the Internet

Framing with black background and rotated makes it look very different: Imgur: The magic of the Internet

Just an idea!

Seconded, I would also like this!