I'm new to using Reg Ex and I think I can manage to use it for more simple tasks. But i just cannot figure out how to replace specific characters within a file name.
So I figured I'd ask advice of those more knowledgeable than myself (which is you guys

I'm trying to rename some jpg's from this format 2012-01-22 14-46-26.JPG
to this format 2012-01-22 14.46.26.JPG
Therefore replacing the dashes "-" in the second part of the file.
I have figured out how to replace all of them, or remove them, but not what I'm after. I'm stuck

Any advice would be greatly received.
Many Thanks in advance