Film specifications#
- Manufacturer
- Efke
- Film
- KB17 / R17
- Speed
- 40
- Process
- B&W
- Formats
- 135-36, 120
- Base
- Triacetate
- Made in
- Yugoslavia
- Status
- Discontinued — replaced by KB 50 / R 50
Character & history#
Ortho-panchromatic classic 1950s style emulsion. Last stock expired in 1993.
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.
| Light | f/2 | f/4 | f/8 | f/16 |
|---|---|---|---|---|
| EV 16 · Snow / beach, bright sun | — | 1/1600 s | 1/400 s | 1/100 s |
| EV 15 · Bright sun | 1/3200 s | 1/800 s | 1/200 s | 1/50 s |
| EV 14 · Hazy sun | 1/1600 s | 1/400 s | 1/100 s | 1/25 s |
| EV 13 · Cloudy-bright | 1/800 s | 1/200 s | 1/50 s | 1/13 s |
| EV 12 · Overcast / open shade | 1/400 s | 1/100 s | 1/25 s | 1/6 s |
| EV 10 · Sunset | 1/100 s | 1/25 s | 1/6 s | 0.6 s |
| EV 8 · Bright interior | 1/25 s | 1/6 s | 0.6 s | 2.5 s |
| EV 5 · Home interior at night | 0.3 s | 1.3 s | 5 s | 20 s |
| EV 3 · City street at night | 1.3 s | 5 s | 20 s | > 1 min |
Push & pull options#
Tell your lab how many stops you pushed or pulled so development is adjusted for the whole roll.
| Adjustment | Rate the film at | Effect |
|---|---|---|
| Pull 1 stop | EI 20 | Lower contrast, finer grain |
| Push 1 stop | EI 80 | More contrast and grain |
| Push 2 stops | EI 160 | Strong contrast, coarse grain, blocked shadows |
| Push 3 stops | EI 320 | Strong 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.
Similar films#
Other black-and-white negative film around ISO 40.
- Argenti Nanotomic X ISO 32
- SPUR DSX ISO 32
- ADOX HR-50 ISO 50
- Agfa Copex Rapid ISO 50
- FILM Ferrania Orto ISO 50
- Film Photography Project Eastman Kodak Hi-Fi 2374 ISO 50
- Ilford PANF Plus ISO 50
- Silberra Orta 50 ISO 50
- Silberra Pan 50 /Ultima 50 ISO 50
- ADOX KB 17 / R 17 / PL 17 ISO 40 · disc.
- Agfa Agfacontour Professional ISO 40 · disc.
- Agfa Isopan F ISO 40 · disc.
- Agfa Isopan F / IF ISO 40 · disc.
- Efke 17 ISO 40 · disc.
- Foma Fomapan Brilant 17 ISO 40 · disc.
- Foma Fomapan F 17 ISO 40 · disc.
- Foma Mikropan 17 ISO 40 · disc.
- Foma Panchro Super ISO 40 · disc.
More Efke films#
Frequently asked questions#
What ISO is Efke KB17 / R17?
40 — set your meter to ISO 40 for box speed.
Is Efke KB17 / R17 still made?
No, it has been discontinued (1974–c1991).
How do I develop Efke KB17 / R17?
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 KB17 / R17 available in 35mm?
Yes — formats: 135-36, 120.
Sources & licences#
- Wikipedia: List of discontinued photographic films — CC BY-SA 4.0
Last updated October 03, 2026 · How we calculate · Sources