Black-and-white negative film · Discontinued

Efke KB 25 / R 25 / PL 25 M

Efke KB 25 / R 25 / PL 25 M is a black-and-white negative film rated at ISO 25, developed in Black-and-white. Below: specs, an exposure guide and similar stocks.

ISO 25Black-and-whiteDiscontinued135120sheet film
ISO 25
Box speed
Black-and-white negative
Type
Black-and-white
Process
Discontinued
Status
1990s–2012
Years made

Film specifications#

Manufacturer
Efke
Film
KB 25 / R 25 / PL 25 M
Speed
25
Process
B&W
Formats
135, 120, sheet film
Base
Triacetate
Made in
Croatia
Status
Discontinued

Character & history#

Ortho-panchromatic classic 1950s style single layer emulsion. 135 (KB 25), 120 (R 25) and sheet size (PL 25 M 4×5, 5×7 and 8×10). Sheet film has retouchable back.

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

Exposure guide at ISO 25#

Sunny 16 for this film: f/16 at 1/25 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—1/1000 s1/250 s1/60 s
EV 15 · Bright sun1/2000 s1/500 s1/125 s1/30 s
EV 14 · Hazy sun1/1000 s1/250 s1/60 s1/15 s
EV 13 · Cloudy-bright1/500 s1/125 s1/30 s1/8 s
EV 12 · Overcast / open shade1/250 s1/60 s1/15 s1/4 s
EV 10 · Sunset1/60 s1/15 s1/4 s1 s
EV 8 · Bright interior1/15 s1/4 s1 s4 s
EV 5 · Home interior at night0.5 s2 s8 s30 s
EV 3 · City street at night2 s8 s30 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 12Lower contrast, finer grain
Push 1 stopEI 50More contrast and grain
Push 2 stopsEI 100Strong contrast, coarse grain, blocked shadows
Push 3 stopsEI 200Strong contrast, coarse grain, blocked shadows
Developing Black-and-white: Traditional black-and-white development (e.g. D-76/ID-11, HC-110, Rodinal, XTOL) — easy to do at home.

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 Efke films#

Frequently asked questions#

What ISO is Efke KB 25 / R 25 / PL 25 M?

25 — set your meter to ISO 25 for box speed.

Is Efke KB 25 / R 25 / PL 25 M still made?

No, it has been discontinued (1990s–2012).

How do I develop Efke KB 25 / R 25 / PL 25 M?

B&W process. Traditional black-and-white development (e.g. D-76/ID-11, HC-110, Rodinal, XTOL) — easy to do at home.

Is Efke KB 25 / R 25 / PL 25 M available in 35mm?

Yes — formats: 135, 120, sheet film.

Sources & licences#

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