Variable filter
Consists of a disc with 5 small filters of different densities arranged in a circle around the centre of the disc. This disc is sandwiched between 2 larger discs each with a hole at the centre small enough for each filter to fill it entirely. The middle disc (with the filters) is pivoted off centre from the other 2.
Object details
| ID: | ZBA0767 |
|---|---|
| Collection: | Astronomical and navigational instruments |
| Type: | Variable filter |
| Display location: | Not on display |
| Creator: | Unknown |
| Date made: | Unknown |
| Credit: | Components. National Maritime Museum, Greenwich, London, RGO Collection |