There are a lot of posts regarding real vs virtual images. I 'think' I understand the distinction clearly, however, there is one thing that I can't quite wrap my head around. What is the "shape" or apparent shape, of a virtual image?
I understand that I can photograph a virtual image because a real image is eventually formed on the sensor. I am not sure what it means for a camera to focus on a virtual image though.
I assume that a virtual image from a mirror, will remain the same proportion to the object, but if a virtual image is formed from a lens, does it become "curved"?
In case I'm not asking the right questions, the very specific use case that I'm trying to understand is a camera in a underwater housing, looking out a curved glass port into water. Everything I have read states the camera focuses on a virtual image that and that the virtual image is curved.
However, all of the lens examples I've found show 2 dimensional - if the image flipped, where it's located, and it's magnification. From that, I don't see how I could determine if a virtual image is curved. Can anyone help guide me to what I'm missing here?