been trying to study perspective since I really suck at it bought Marshall vandruffs course also got a book. Anyways I have been struggling with the sphere how can I improve sometimes my ellipse's are just wrong and it doesn’t make a sphere(one is too long or short)Also putting an ellipse inside a cube is hard along with trying to see trough it. Any advice?

Hello there I was hoping I could get some feedback and critique on my studies. I'm struggling and would love some help thanks!. This is for Spine studies 7-10. Thanks!

Hello there I was hoping I could get some feedback and critique on my studies. The first 2 pictures are before the video and the later 2 After the draw skelly video. Thanks!