Own

Brand	Focal Length	Max Fstop	Mount	Ø	Notes
Industar-69	28mm	f/2.8	M39	22.5mm	Lomo Russian rangefinder pancake
Pentacon	29mm	f/2.8	M42	55mm	German lens with an interesting look
Chinon	35mm	f/2.8	M42	-	Japanese lens
Canon	50mm	f/1.8	FD	55mm	No marking = multicoated (SSC)
Industar	50mm	f/3.5	M42	33mm?	50-2, 50mm Russian pancake
Helios	58mm	f/2	M42	52mm	44M-5. 44-2 has “character”, 44M-5 is sharpest
Vivitar	85-205mm	f/3.8	M42	58mm	Thrift store zoom

Wanted

Canon FD Mount

Brand	Focal Length	Max Fstop	Mount	Ø	Notes
Canon	17mm	f/4	FD	72mm	Widest, priciest
Canon	20mm	f/2.8	FD	72mm	Wider, spendy
Canon	24mm	f/2.8	FD	52mm	Convex front element runs close to filters
Canon	28mm	f/2.8	FD	52mm	More common, cheapest of the wides
Canon	35mm	f/2	FD	55mm	Rare thoriated “concave” early FD
Canon	55mm	f/1.2	FD	58mm	Versions: cheap one, the Aspherical, and later “L”
Kiron	105mm	f/2.8	FD	-	1:1 Macro. Very sharp, $. AKA: Ricoh Rikenon, Vivitar

M42 Mount

Brand	Focal Length	Max Fstop	Mount	Ø	Notes
Carl Zeiss Jena	20mm	f/2.8	M42	-	Spendy but probably best for APSC
Asahi Pentax	28mm	f/3.5	M42	-	Super-Takumar, cheaper but not fast
Carl Zeiss Jena	35mm	f/2.4	M42	-	Flektagon
Mir-1	37mm	f/2.8	M42	-	Soviet with character, cheap
Asahi Pentax	50mm	f/1.4	M42	-	Rare version is 8 element
Carl Zeiss Jena	50mm	f/1.8	M42	-	Pancolar
Meyer Optik	50mm	f/2.8	M42	-	Domiplan, weird German bokeh
Industar	50mm	f/3.5	M42	-	50-2. Soviet pancake, cheap
Tomioka-Made	55mm	f/1.4	M42	-	OEM for Super-Takumar
Asahi Pentax	55mm	f/1.8	M42	-	Cheapest Super-Takumar
Jupiter-9	85mm	f/2	M42	-	Russian portrait lens
Meyer Optik	100mm	f/2.8	M42	-	Gorlitz Trioplan. Weird bokeh.
Tair 11	135mm	f/2.8	M42	-	20 aperture blades. “T” = television
Tamron	35-80mm	f/2.8-3.8	M42	-	SP Adaptall. Very cheap, decent.