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Pathescope B&W Reversal Processing
| First Developer (1947) | ||
| Sodium Sulphite (anh) | 20 g | |
| Para-phenylene-diamine | 10 g | |
| Potassium Bromide | 8 g | |
| Sodium Hydroxide | 8 g | |
| Water to | 1 litre | |
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| Reversal Bath | ||
| Water |
750ml | |
| Potassium Dichromate | 5 g | |
| Sulphuric acid (conc) - see note | 10 ml | ADD THE SULPHURIC ACID DROP BY DROP TO THE 750ml WITH CARE. |
| Water to | 1 litre | |
| Clearing Bath | ||
Sodium Sulphite (anhyd) |
20 g | |
| Sodium Hydroxide | 0.8 g | |
| Water to | 1 litre | |
| Second Development | ||
| Metol | 2 g | |
| Sodium Sulphite (anhyd) | 75 g | |
| Hydroquinone | 10 g | |
| Sodium Carbonate (anhyd | 25 g | |
| Potassium Bromide | 2 g | |
| Water to | 1 litre | |
| Fixer | ||
| Sodium Thiosulphate |
250 g | |
| Sodium Metabisulphite | 20 g | |
| Water to | 1 litre | |
| First Developer | Develop 17 - 18°C (62 -64°F) 8-10 minutes |
|
| Wash | 7-10 mins | All other solutions at 16 -17°C (60 -62°F) |
| Bleach | 5 - 7 minutes | |
| Wash | Wash 1 - 2 minutes | |
| Clearing Bath | Clear for 2 - 3 minutes | |
| Wash | 2 mins | |
| Re-exposure | Expose to white light. No specific time is given but 5 - 10 mins
1.5 metres from 500 watt bulb should be sufficient |
|
| Second Development | Development to finality, approx 3 minutes. | |
| Wash | 10 minutes | |
| Fixer | Fix in normal acid fixing bath. | |
| Wash | 20 mins | |
| Alternative First Developer (1954) | ||
| Sodium Sulphite (anhyd) | 70 g | |
| Hydroquinone | 10 g | |
| Sodium Carbonate (anhyd) | 35g | |
| Potassium Bromide | 8 g | |
| Potassium Thiocyanate | 3 g | |
| Sodium Hydroxide | 5 g | |
| Water to | 1 litre | |
| British Journal Photographic Almanac 1947 & 1954 |