Canon ER-h Eyecup

I was skeptical about the asymmetrical shape, but it really does block stray light perfectly when shooting in bright sun. The 360° rotation is a nice bonus for framing vertical shots without adjusting the camera.

The rotating design makes it so easy to switch between shooting portrait and landscape without taking my eye off the viewfinder. Really glad I picked this up for my R3.

I was skeptical about the asymmetrical shape at first, but it really does block stray light perfectly when shooting outdoors. The rotating design makes it easy to adjust for vertical or horizontal shots.