The Ilford SP816T is a black and white film. It was manufactured by Ilford in the UK and designed as a film for traffic control. It was offered by ILFORD Imaging UK Limited until the 2000s.
The ILFORD SP816T is a black and white film designed specifically for photographic traffic surveillance, both fixed and mobile. It has extended red sensitivity up to 740nm, making it ideal for use with in-camera red filters or for traffic monitoring with red flash.
The film has full panchromatic sensitivity, ensuring good image contrast with or without the use of a red filter. It has a wide exposure latitude and can be used under various exposure conditions, both day and night.
SP816T film can be used with all the red filters normally used for photographic traffic control, RG665 being the most common. It was recommended by Ilford to traffic monitoring operators that the red filter be used over the flash unit during the day and night, and over the camera lens during the day. In addition, a polarizing filter is recommended over the camera lens to reduce reflections from car windows.
Developing the film
The Ilford SP816T is developed in a black and white developer. You can hand in the exposed film in some developing laboratories in Germany. However, it is also possible to do the development yourself. A well chosen developer can influence the result positively and negatively.
Of course, the film can be processed in Ilford developers. But it can also be processed in other developers.
Development times for the Ilford SP816T
| Developer | Dilution | ISO | Time | Temperature |
|---|---|---|---|---|
| ILFOTEC DD-X | 1+9 | ISO 400 | 10 min | 20 °C |
| ILFOSOL S | 1+9 | ISO 400 | 9:30 min | 20 °C |
| ILFOTEC HC | 1+15 | ISO 400 | 5 min | 20 °C |
| ILFOTEC HC | 1+31 | ISO 400 | 9 min | 20 °C |
| ID-11 | Stock | ISO 400 | 10 min | 20 °C |
| MICROPHEN | Stock | ISO 400 | 8:30 min | 20 °C |
| PERCEPTOL | Stock | ISO 400 | 14:30 min | 20 °C |
| Agfa Atomal | Stock | ISO 400 | 9 min | 20 °C |
| Agfa Refinal | Stock | ISO 400 | 8 min | 20 °C |
| Studional | 1+15 | ISO 400 | 7 min | 20 °C |
| D-76 | Stock | ISO 400 | 10 min | 20 °C |
| Tetenal Neotenal | Stock | ISO 400 | 8 min | 20 °C |
Calculation of the development solution
| Dilution | Developer (ml) | Water (ml) |
|---|---|---|
| 1+9 | 50 | 450 |
| 1+15 | 31 | 469 |
| 1+31 | 16 | 484 |
| Stock | 500 | 0 |
Availability and alternatives
The SP816T was only available in 35mm format. It was coated on a 0.075 mm gray polyester base that provided halation protection and would not tear off in the camera. It was sold in cartridges of 36 frames and by the meter in lengths of 17m and 30.5m without spool or core for use in stationary units.
Production of the film stock was discontinued. An alternative for 35mm format is the Ilford HP5* a possibility. It is very flexible in use and available in many formats.
