What size lens do I need?
11001
What is "angle of view" in photography?
91826
How do I install the Ask Ubuntu Unity Lens, and how do I use it?
87632
How do I find the thread diameter of my lens?
49187
What is focal length and how does it affect my photos?
40865
What should I do when I have lenses with different filter thread sizes?
116792
Is there a single lens suited for flying birds, mountains, and close-up portraits?
131157
Should I replace the Canon 18-55mm f/3.5-5.6 kit lens with a 40mm f/2.8 or 50mm f/1.4?
18645
Is a UV Filter required/recommended for lens protection?
114778
What is the difference between DX format and FX format lenses, and which to choose for what purpose?
17968
Does 4.0-72mm on the lens when equivalent focal length is 24-432mm mean crop factor of 6×?
41048
If I have a 18-55mm lens, is there a point in buying a 35mm prime lens?
1032
What is the reference point that the focal length of a lens is calculated from?
10956
How do I choose a macro lens for a Canon APS-C camera?
6598
How to calculate the correct focal length needed for a subject of a given size and distance?
46184
What should I consider when purchasing a macro lens?
18161
How would one use filters with the "bulb"-like shape front element lenses?
12460
Why prefer the 18-55mm and 55-250mm lenses vs 18-200mm?