What a Grade Is
A paper grade indicates the density range converted into full print tones. A soft paper accepts a wide negative range. A hard paper accepts a narrow range.
The measure is the useful log exposure range. One stop equals 0.30 in log exposure.
| Grade | Approximate log exposure range |
|---|---|
| 0 | 1.50 |
| 1 | 1.30 |
| 2 | 1.05 |
| 3 | 0.90 |
| 4 | 0.75 |
| 5 | 0.60 |
Each whole step shortens the range by roughly half a stop. For a successful print, the negative's density range must fit the paper's exposure range.
Paper Surface choices also affect maximum black.
Variable Contrast
Variable-contrast papers like Multigrade carry two emulsions in one coating. One emulsion has high contrast, and the other has low contrast. Enlarger filtration controls the balance between them.
- Yellow light exposes the soft emulsion.
- Magenta light exposes the hard emulsion.
- No filter at all gives roughly grade 2 under tungsten.
Filters span from 00 to 5. Crucially, grades 00 to 3½ all need the same exposure. However, grades 4 and 5 need twice as much exposure. A 12-second base at grade 3 becomes 24 seconds at grade 4.
Common pitfall: reaching for a hard grade when a print looks dull. Dullness usually stems from underexposure, not low contrast.