I am 100% sure that this is possible, but I'm also 100% sure that I can't tell you how. LOL! Does that help?

Reason I say it's possible is that there are many applications I've seen in the wild that will snap a pic and return it to a userform. The questions, though, comes down to:
-Does the camera expose its object model to code?
-Is there an API that you can use to trigger it?
-What format is the default output?

Once you've got all that, then things might be easy. Copying/renaming/deleting files is really easy in VB(A), so you'd just need to find the most recent picture and move/rename it to what you want. I'm sure that you'd be able to come across code on the internet to convert and scale your picture from one format to another. And from there it's importing it into your userform which again should be do-able.

The part that gives me most cause for concern is sending commands to your camera. Now... if you had a camera that always snapped a pic and dumped it immediately into a directory... Then you could just manually tigger your macro after you'd taken the picture. Copy it to a new folder, rename it, delete the original, and you're always clean for next time. Then it's the image conversion etc...

Hopefully some of this helps a bit conceptually, if nothing else.