Lens Flares on purpose
61989
How can I intentionally include lens flare in my photographs?
133548
How can a speedbooster improve the light performance of a lens?
124074
Does stacking more lens filters decrease overall image quality?
51013
How to correct flares and sharply focus on my telescope when viewing planets.
103113
Why do zoom lenses and compact cameras have varied maximum aperture across the zoom range?
62822
How can lens cause consistent front or back focus?
52967
Can screw-on macro lenses produce decent results?
156969
How does autofocus work?
87470
Is it reasonable to use a ring flash that encircles the lens for non-macro (general) shots?
113574
What is a macro lens?
67822
How to determine lens undistortion values for motion tracking?
79654
What is the effect of the number of cross-type focus points on sharp focus?
52691
Sign convention in optics
101960
Why are crop lenses indicated with focal lengths they don't have?
54818
Why does fungus form in lenses, and how to get rid of it?
94456
Why does my one lens have different exposure (t-stop) than my other lens?
51290
Does my crop sensor camera actually turn my lenses into a longer focal length?