| FP4 plus | |
|---|---|
 | |
| Maker | Ilford Photo |
| Speed | 125/22°[1] |
| Type | B&W print |
| Process | Gelatin-silver |
| Format | 35mm, 120, sheets |
| Application | General |
| Introduced | 1990 |
| FP4 | |
|---|---|
| Speed | 125 ASA |
| Type | B&W |
| Introduced | 1968 |
| Discontinued | 1990 |
| Replaced by | FP4 plus |
| FP3 | |
|---|---|
 | |
| Speed | 64 ASA, 125 ASA (1960) |
| Type | B&W |
| Introduced | 1942 |
| Discontinued | 1968 |
| Replaced by | FP4 |
| FP2 | |
|---|---|
| Speed | 40 ASA |
| Type | B&W |
| Introduced | 1939 |
| Discontinued | 1942 |
| Replaced by | FP3 |
| FP | |
|---|---|
| Speed | 40 ASA |
| Type | B&W |
| Introduced | 1935 |
| Discontinued | 1939 |
| Replaced by | FP2 |
FP is a cubic-grain[2] black-and-white film from Ilford Photo with a long history.[3] It originated as Fine grain Panchromatic roll film in 1935. Like its faster partner product, HP film, it has gone through a number of versions since then, with the latest being FP4 plus (FP4+ for short).
The film is known for being versatile, with usable results even when underexposed two stops or overexposed six stops.[1] This is due to the fact that FP4 features a double layer emulsion. It combines a low sensitive fine grain layer and a highly sensitive layer with larger grains. This kind of film was already known in the 1920s and 1930s (e.g. Agfa Isopan F 17/10° DIN). Being perfect for the amateur's 6x9 roll film cameras these old types lacked sharpness in the 24 x 36 mm format due to the overall thickness of both layers. But the FP4 of 1968 combined an amateur-friendly double layer emulsion with the sharpness of a typical thin layer emulsion. This was possible because both layers together were only 7.5 µm thick.[4]
References
- 1 2 "Archived copy" (PDF). Archived from the original (PDF) on 2016-06-04. Retrieved 2016-05-23.
{{cite web}}: CS1 maint: archived copy as title (link) - ↑ "Film stock review: ILFORD FP4 PLUS in 35mm, 120 format and sheet film". Emulsive.org. 29 June 2015. Retrieved 22 March 2019.
- ↑ "Ilford History and Chronology". Photomemorabilia.co.uk. Retrieved 2007-07-27.
- ↑ Solf, Kurt Dieter (1975). Fotografie. Frankfurt am Main: Fischer. p. 28.