It's a mix between PNG and JPG if I recall... However, for the second chapter, I'll switch to JPG for a smaller size.
And thank you! I'm glad that you like her name :)
;-)
png is only good for buttons and ui elements. Anything coming out of a rending app should be compressed lossy with webp and appropriate settings. You can even get away with half the size of jpg in many cases.
From my understanding, the rendering app did practically the opposite of what lossy webp will do. So it should compress fantastically. It used math to flesh out the picture and render the model. So math should be able to compress it even better than a natural picture.