Quote Originally Posted by uv8452 View Post
The viewfinder image of digital SLR cameras is smaller than those of analog SLR.
I tried to understand the optical basics and experimented a little bit. Without success. Olympus e-410.
Has somebody experience with a self made magnifier eyepiece?
Every hint will be welcome.
Ulrich V.
Your Amazon search-fu is weak. Go here...

https://www.amazon.com/s?k=camera+ey...ref=nb_sb_noss

or, if that doesn't work, go to Amazon and use the search phrase "camera eyepiece magnifier".