User should be able to render multiple vessels from the same distance to compare scale.

Seconded. I know this is an old request, but it would make Kronal VV so much better.
Ideally it would be great if the zoom/image size functionality could be reversed; so that rather than the scale changing when using the zoom function, the scale could be 'fixed' and then the image size is reduced or enlarged. This would allow us to create multiple screenshots, and the vessels would always be the same relative size; and could be pasted into a single image without additional re-scaling.