Color negative film · Discontinued

Agfa Agfacolor CN17S

Agfa Agfacolor CN17S is a color negative film rated at ISO 40, developed in Agfacolor. Below: specs, an exposure guide and similar stocks.

ISO 40AgfacolorDiscontinued135120
ISO 40
Box speed
Color negative
Type
Agfacolor
Process
Discontinued
Status
1966–1968
Years made

Film specifications#

Manufacturer
Agfa
Film
Agfacolor CN17S
Speed
40
Process
Agfacolor Process N
Formats
135, 120
Base
Triacetate
Made in
Germany
Status
Discontinued — replaced by Agfacolor CNS

Character & history#

S for Special. General purpose double masked color negative film with extra fine grain.

Description adapted from Wikipedia’s “List of discontinued photographic films” (CC BY-SA 4.0).

Exposure guide at ISO 40#

Sunny 16 for this film: f/16 at 1/40 s in bright sun. Negative film tolerates 2–3 stops of overexposure; slide film needs accuracy within about ⅓–½ stop.

Lightf/2f/4f/8f/16
EV 16 · Snow / beach, bright sun—1/1600 s1/400 s1/100 s
EV 15 · Bright sun1/3200 s1/800 s1/200 s1/50 s
EV 14 · Hazy sun1/1600 s1/400 s1/100 s1/25 s
EV 13 · Cloudy-bright1/800 s1/200 s1/50 s1/13 s
EV 12 · Overcast / open shade1/400 s1/100 s1/25 s1/6 s
EV 10 · Sunset1/100 s1/25 s1/6 s0.6 s
EV 8 · Bright interior1/25 s1/6 s0.6 s2.5 s
EV 5 · Home interior at night0.3 s1.3 s5 s20 s
EV 3 · City street at night1.3 s5 s20 s> 1 min

Push & pull options#

Tell your lab how many stops you pushed or pulled so development is adjusted for the whole roll.

AdjustmentRate the film atEffect
Pull 1 stopEI 20Lower contrast, finer grain
Push 1 stopEI 80More contrast and grain
Push 2 stopsEI 160Strong contrast, coarse grain, blocked shadows
Push 3 stopsEI 320Strong contrast, coarse grain, blocked shadows

Long exposures#

Most films suffer reciprocity failure beyond about 1 second: they need more exposure than the meter says. As a rule of thumb add ⅓–1 stop for 1–10 s and 1–2 stops beyond 10 s for older emulsions; modern T-grain films (and Fuji Acros) need much less. Check the manufacturer's datasheet.

More Agfa films#

Frequently asked questions#

What ISO is Agfa Agfacolor CN17S?

40 — set your meter to ISO 40 for box speed.

Is Agfa Agfacolor CN17S still made?

No, it has been discontinued (1966–1968).

How do I develop Agfa Agfacolor CN17S?

Agfacolor Process N process.

Is Agfa Agfacolor CN17S available in 35mm?

Yes — formats: 135, 120.

Sources & licences#

Last updated October 03, 2026 · How we calculate · Sources