useful links:
Using filters with vintage cameras
http://throughavintagelens.com/2013/09/vintage-filter-systems/
Guide to thread pitches used throughout the site
ES European standard male threads 0.75 standard threads today
E European fine male threads 0.5: for older cameras
F fine male threads 0.5mm between threads - same as E
C Coarse male threads 1.0
M medium male threads 0.75... standard threads today
FR fine (0.5) female
MR med (0.75) female
NFT slim > no front threads
SO slip-on (over lens barrel)
SS set screw (tightens over lens barrel)
*step-up, step-down rings: First number is your lens size, second the filter size.
Guide to condition of filters for sale
*new filters
“new” - current or recent packaging.
“n/o” - new filters in older packaging 7+ years.
NIB...new-in-box
NIC...new in original leather or plastic case
( n/o B+W and Heliopan filters are non-slim )
*pre-owned filters
“looks new” may be new (?) - out of original packaging
“clean” or “very clean” - used, near-mint condition - no flaws.
vg - good glass, some wear on frame
cs - with original leather or plastic case
unmtd - unmounted glass
MC - multi-coated; SC - single coated
(*) before the size - quantity discounts available
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All Nikon, B+W, Heliopan and other German filters are black anodized brass.
B+W and Heliopan filters are SC “single coated” on both sides
B+W “MRC” filters have “multi-resistant coating”
Heliopan “SH-PMC” filters have “super-hard premium multi-coating”
All other round filters are black anodized aluminum unless “chrome”.
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*Linear Polarizers are for new mirrorless and older manually operated cameras
*Circular Polarizers recommended for AF and Digital cameras
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Guide to Neutral Density filters
ND Wratten # Filter factor (ff) Increase exposure stops
0.1 1.25 1/3
0.2 1.50 2/3
0.3 2x 1
0.4 2.5 1-1/3
0.5 3 1-2/3
0.6 4x 2
0.7 5 2-1/3
0.8 6 2-2/3
0.9 8x 3
1.0 10 3-1/3
1.2 16 4
1.8 64 6
2.0 100 6-2/3
2.4 8
2.7 9
3.0 1000 10
4.0 10k 13-1/3
Basics for digital or film

UV - Haze Basic reduction of UV light...
Filter Factor 0 - 0 stops

Skylight 1A, 1B - B+W KR1.5 - Nikon L1A, L1B
Cuts UV light - pinkish cast for blue haze reduction...
Filter Factor 1 - 0 stops

Linear / Circular Polarizer
General use in outdoor photography - produces deeper skies and alters reflections.
Filter Factor 3-4...1-2/3 - 2 stops


Infrared 89B - B+W 092 - Hoya R72
Infrared 87 - B+W 093 - Hoya RM90

Enhancing Filter - Hoya Intensifier
Intensifies the yellow, orange, red spectrum while not affecting other colors, use with Polarizer to intensify blue skies. Enhances faded fabrics, fall foliage and landscape.
Filter Factor 1.4 - 1/2 stop
filters for black and white photography


General rule:
filters lighten their own color and darken their opposite
Yellow 5 - Y1 - Nikon Y44
Light yellow filter for mild contrast...high-altitude UV...Filter Factor 1.4 - 1/2 stop

Yellow 8 - Y2 - B+W 022 - Hoya K2 - Nikon Y48
This medium yellow filter offers the most correct tonal range contrast for clouds against blue skies...
Filter Factor 2 - 1 stop

Yellow 12 - Nikon Y52
Cuts haze in aerial work; used with color infrared; more contrast than yellow 8
Filter Factor 2.2 - 1 stop

Yellow 15 - B+W 023
Enhances landscapes, marine scenes and aerial photography with more dramatic effects than yellow 8 ...
Filter Factor 2.5 - 1-1/3 stop

Orange 16 - B+W 040 - Hoya G
More dramatic effect than Yellow 15...
Filter Factor 2.5 - 1-1/3 stop

Orange 21 - B+W 041 - O2 - Nikon 056
Absorbs blue and blue-greens.
Blue skies darken with dramatic cloud contrasts.
Foliage blackens.
Filter Factor 7 - 2-2/3 stops

Red 23A
Light red producing contrast effects that darken skies, water, rock formations and architecture...
Filter Factor 6 - 2-1/3 stops

Red 25A - B+W 090 - Nikon R60
Dramatic sky effects and cloud contrast.
Useful with Infrared films
Filter Factor 8 - 3 stops

Red 29 - B+W 091
Dramatic sky effects and cloud contrast. Useful with Infrared films. Deeper effect than 25 Red.
Filter Factor 10 - 4-1/3 stops

Yellow-Green - Hoya XO - B+W 060
Used with outdoor portraiture for good skintones when landscape is important. Enhances highlites in foliage, grass and trees. Same sky contrast as yellows.
Filter Factor 2.5 - 1-1/2 stop

Green 11 - B+W 061 - Hoya X1
Used with outdoor or studio portraiture for rich skintones;
Enhances shadows and highlites in foliage, grass and trees...Filter Factor 4 - 2 stops

Green 58
Dramatically lightens and enhances shadows and highlites in foliage, grass and trees.

Cyan Blue 38 - B+W 080, 081
Minimizes contrast; Bleaches daytime skies.

Blue 47, 47B
Accentuates fog; minimizes contrast giving shots a
wintery effect
warming filters for digital or film

Tiffen 812 - Tiffen FX Warm
Absorbs bluish haze in scenics; Adds warmth to skintones, similar to a dense skylight.
Filter Factor 1.5 - 2/3 stop

81A
Converts Tungsten 3200K Type B film to 3400K w/ indoor lighting
Warms up scenes and portraiture on overcast days w/ Daylight film... Filter Factor...1.4 - 1/2 stop

81B
Used with outdoor portraiture for good skintones when landscape is important. Stronger effect than 81A
Filter Factor 1.4 - 1/2 stop

81C - B+W / Heliopan KR3
Same as 81B but has increased effect
Filter Factor 1.5 - 2/3 stop

81EF
Same as 81C but has increased effect
Filter Factor 2.0 - 1.0 stop
color correction / color balance

Using Cinestill films
https://cinestillfilm.com/pages/frequently-asked-questions

80A - B+W KB15 - Nikon B15
Balances daylight film for use with most standard household tungsten lighting or studio lighting...converts 3200K to 5500K....Filter Factor 2.4 - 1-1/3 stops

80B - B+W KB12 - Nikon B12
Balances daylight film for use with most standard photo flood lamps and on-camera flash.
converts 3400K to 5500K...Filter Factor 2 - 1 stop

80C
Balances daylight film for use with most high intensity photo flood lamps and on-camera flash....Filter Factor 1.9 - 1 stop

82A - Heliopan B1.5 - B+W KB1.5
Reduces warmth during early morning and late afternoon while maintainig natural skintones.
Filter Factor 1.3 - 1/3 stop

82B - Heliopan B3 - B+W KB3
Same as 82A but has increased effect.
Filter Factor 1.4 - 1/2 stop
82C...Filter Factor 1.5 - 2/3 stop

85
Creative strong warming filter. Type-A lighter - Cine-still Tungsten
Filter Factor 2 - 1 stop

85A - Heliopan R12
Creative strong warming filter deeper than 85.
Tungsten Type A film - Cine-still Tungsten
Filter Factor 2 - 1 stop

85B - Heliopan R15
Balances Type B indoor film for outside - Cine-still Tungsten
Filter Factor 2.1 - 1 stop

85C
Creative strong warming filter. Balances Type B indoor film for outside like 85B but slightly cooler - Cine-still Tungsten
Filter Factor 2 - 1 stop

FL-D daylight
Balances daylight film to indoor fluorescents reducing green cast... Filter Factor 2 - 1 stop

FL-B
Balances Type B film to indoor fluorescents
Filter Factor 2 - 1 stop

FL-W
Balances daylight film to tungsten corrected or daylight simulated fluorescents.
Filter Factor 2 - 1 stop

CC 30 Magenta
General fluorescent correction with indeterminate ambient fluorescent lighting.