Color slide film · Discontinued

ORWO UT 23

ORWO UT 23 is a color slide film rated at ISO 160, developed in ORWO 9165. Below: specs, an exposure guide and similar stocks.

ISO 160ORWO 9165Discontinued135120
ISO 160
Box speed
Color slide
Type
ORWO 9165
Process
Discontinued
Status
1982–1989
Years made

Film specifications#

Manufacturer
ORWO
Film
UT 23
Speed
160
Process
ORWO 9165
Formats
135, 120
Base
T/P
Made in
GDR
Status
Discontinued

Character & history#

High speed slide film for daylight. Roll films had PET base.

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

Exposure guide at ISO 160#

Sunny 16 for this film: f/16 at 1/160 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 s
EV 15 · Bright sun—1/3200 s1/800 s1/200 s
EV 14 · Hazy sun—1/1600 s1/400 s1/100 s
EV 13 · Cloudy-bright1/3200 s1/800 s1/200 s1/50 s
EV 12 · Overcast / open shade1/1600 s1/400 s1/100 s1/25 s
EV 10 · Sunset1/400 s1/100 s1/25 s1/6 s
EV 8 · Bright interior1/100 s1/25 s1/6 s0.6 s
EV 5 · Home interior at night1/13 s0.3 s1.3 s5 s
EV 3 · City street at night0.3 s1.3 s5 s20 s

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 ORWO films#

Frequently asked questions#

What ISO is ORWO UT 23?

160 — set your meter to ISO 160 for box speed.

Is ORWO UT 23 still made?

No, it has been discontinued (1982–1989).

How do I develop ORWO UT 23?

ORWO 9165 process.

Is ORWO UT 23 available in 35mm?

Yes — formats: 135, 120.

Sources & licences#

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