Theory is a statement of how and why particular facts are related. In the context of JAPB, theory is all that which is not directly pertaining to specific items of gear, but more to how gear relates to other gear (in the context of taking photos).
See below for a list of the more detailed musings. You can also look at our glossary for explanations of the more simple* concepts and terms.
* simple, as in “explainable in a few paragraphs”.
Articles on lens mounts:
Articles on lens mounts in general:
• An introduction to lens mounts
• Identifying a lens mount
• Intermediate mounts
• Being strategic with adapters
• Set lenses
Articles detailing specific lens mounts:
• Altix
• Canon EF
• Canon FL, FD and newFD
• Canon R
• Canon RF
• Contax G
• Contax / Kiev
• Contax/Yashica
• DKL
• Exakta
• Four Thirds
• Fujica X
• Fujifilm G
• Fujifilm X
• Icarex BM
• Konica AR
• Konica F
• L mount
• Leica M
• Leica R
• LTM (Leica Thread Mount)
• m42
• Mamiya Z
• Micro Four Thirds (MFT)
• Minolta A (Sony A)
• Minolta SR
• Nikon 1
• Nikon F
• Nikon S
• Nikon Z
• Olympus OM
• Pentacon Six
• Pentax K
• Petri FT
• Praktica B
• Praktina
• Rollei QBM
• Sony FE (including Sony E)
• T-4/TX
• Tamron Adaptall (1&2)
• Topcon UV
• Yashica AF
(and more to come)
JAPB series on optical flaws and aberrations:
• Introduction
• Distortions (optical)
• Vignetting
• Veiling and Ghosting (flare)
• Atypical ghosts
• Spherical aberration
• Focus shift
• Comatic aberration (‘Coma’)
• Astigmatism
• Chromatic aberrations
• Field curvature
• Uniform colour casts
• Partial colour casts
• Diffraction (even though it’s not an optical flaw or aberration)
JAPB series on exposure
• Introduction
• The components of exposure (and the side-effects)
• Working with Exposure (in practice)
• Various approaches to exposure automation
• EV tables, and how to use them
Articles that are not part of a series:
• Autofocus
• Effective Aperture
• Legacy, Classic and Vintage lenses? What are those?
• Practicalities of adapting lenses