I have APHANTASIA (and you may too...without realising it!)

It's hard! There are some professional artists who are aphantasic, e.g. this YouTube video talks about it ▶ this video IIRC, the artist does lots of sketches, and looks at them to see what looks right. And also uses computer models to get angles of what she's drawing which she struggles with otherwise.

A little slow, but this video is fantastic for describing the feeling of aphantasia and it's sort of doubly fascinating that the incredibly talented artist who made it suffers from it (as I'm the flip side, great at visualizing and horrid at creation) ▶ this video

So I have aphantasia, and I first realized when talking to someone about mental images and memories. They have photorealistic pictures in their mind, or even video scenes like a movie. At my best I have something like an expressionist painting with words and concepts arranged spatially on blobs of color representing the object. More typically, just blackness. Here is another description of it, and a test in the first part: ▶ this video