Basic3D makes my image smaller

Hi all,

So I am making a small video with pictures in it. And I wanted to make a picture flip over and I do this with Basic 3D and then the function 'swivel '. And actually it does exactly what I want which is good. However, the only thing is, as you can see in this video (https://imgur.com/a/VMjQ6lj) it makes the size of my picture smaller and therefore not fit the screen during the animation. The weird part however is, that it seems to get its original size back when I let go of the blue line thingy. So I think okay maybe the rendering is slow but eventually it will be okay. However, this is not the case, when I try to export my video the size in the video is still small, see image.

Does someone know how to fix this? Do I need to change something in my export settings?

Thanks in advance