General Information

Serial #

N/A

Part Number

1

Total Parts

1

AKA

N/A

Patents

N/A

General Description

Synthetic with metal hardware

Dimensions

Note: These reflect the general size for storage and are not necessarily representative of the object's true dimensions.

Length

6.6 cm

Width

6.4 cm

Height

N/A

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Photography

Category

Still camera accessories

Sub-Category

N/A

Manufacturer

AKA

Johnson

Country

Unknown

State/Province

Unknown

City

Unknown

Context

Country

Unknown

State/Province

Unknown

Period

probably 1950s

Canada

A piece of equipment used with a Bolsey camera purchased by the donor around 1951 in Flint, Michigan while he was a co-op student with General Motors. He used the camera for scenic and portrait photography while living in Michigan and travelling throughout the U.S. and Mexico, and upon his return home to the U.K.

Function

A device used to calculate the correct camera lens opening for a proper exposure depending on light available.

Technical

One of a series of Johnson plastic disc type calculators for use in determining exposure under daylight condition for all types of still and cine colour reversal films. Weather conditions and seasonal variations in lighting are considered. The calculations were compiled in accordance with the British Standards exposure tables BS935 and applies to latitudes 45-degrees to 55-degrees north, but correct light value tables for other latitudes were supplied for pasting over the standard values. (Ref. 1)

Area Notes

Unknown

Details

Markings

Red lettering on front reads 'JOHNSON FLASH EXPOSURE CALCULATOR'/ Black and red lettering and markings on front and back for scales and instructions.

Missing

Appears complete

Finish

White synthetic/ gold coloured ring

Decoration

Red logo on back reads 'JS'