The ability to squint and focus - what is it called and is it used in optics?
37531
Pinhole camera: How "How to See Without Your Glasses" works?
147537
Detecting an ellipse in a glaucoma photo
47620
How does a circular lens produce rectangular shots?
60690
Optical microscope magnification limits?
142585
Is there a theoretical maximum for refractive index?
101300
What to look for in a wide angle lens?
117114
Naturally improve eyesight
21637
How does one use circular polarizers?
113163
Why do some lenses focus past infinity?
113574
What is a macro lens?
26351
What macro techniques offer an alternative to expensive optics?
23865
Why do prisms work (why is refraction frequency dependent)?
17126
Significance of the second focus in elliptical orbits
31697
Do eyeballs exhibit chromatic aberration?
6871
Is it possible to blur an image in such way that a person with sight problems could see it sharp?
130932
Effective Refractive Index
58732
Can you concentrate on a special ability while also concentrating on a spell?