Took a lot of work and concentration. Of course I'm using the mirror tool for a piece like that, with the canvas split in 4. But to make one picture look like something else while upside down, makes my head hurt just thinking about it.
Hence the name.
it must take hours to do, way beyond my skillset
Takes a fair amount of time. Could have kept going as well. So many finer details could be added but I sometimes wonder if it's worth putting it in or if it just gets overlooked.
always see different things the more you look, guess the brain doesn't take it all in at frst glance
Just like staring at the clouds. Same effect. Hard to explain. Even that black and white image I placed in a comment; look closely and you might start seeing the cave painting I stashed away in there.