How to calculate the focal length for old lenses (m42 or m39) mounted on Sony Nex?
129196
Does crop factor still apply to a vintage film SLR lens?
148588
Lens correction in darktable when my lens isn't known?
49187
What is focal length and how does it affect my photos?
95190
What should I look for in lenses for long range and close up animal and natural shots?
18161
How would one use filters with the "bulb"-like shape front element lenses?
26448
How does a DX-format sensor support FX lenses?
7818
How can I get dramatic shallow DOF with a kit lens?
96529
How can I calculate magnification ratio I get by reversing a lens?
42940
How do I calculate the distance of an object in a photo?
83556
What are the theoretical minimum and maximum apertures?
101736
What is the difference between Canon "L" lenses and non-L lenses?
37632
How to compare the focal length of a 50mm prime lens with the default lens of a point and shoot camera?
7212
How to read ND filter description?
41934
How do zoom, magnification, and focal length relate?
22374
What methods can be used to micro-adjust autofocus of a camera body to a particular lens?
145744
How do I meter for long exposures (10+ minutes)?
86838
What do the red values mean on the distance scale of a lens?