Cooke Series XVa Triple Convertible Lens
Specifications for Comprehensive Focal Length Combinations

Front + Back

Back

Front

Back + Back

Front + Front
Focal Length

311mm

476mm

646mm

273mm

368mm
Aperture Range

f/6.8 to f/90

f/11 to f/90

f/16 to f/90

f/5.6 to f/90

f/8 to f/90
Format
Diagonal
Angle of View

8x10
325mm
55 deg.

8x10
325mm
38 deg.

8x10
325mm
28 deg.

8x10
325mm
61 deg.

8x10
325mm
48 deg.

Max. Useable Image Circle at Infinity
(Angle of View)
(Use Aperture)

381mm/15 in.
(63 deg.)
(f/16)


452mm/17.8 in.
(51 deg.)
(f/32)


452mm/17.8 in.
(39 deg.)
(f/32)


324mm/12.75 in.
(61 deg.)
( f/16)


420mm/16.5 in.
(60 deg.)
( f/16)

Max. Useable Image Circle at 10 feet and less
(Use Aperture)

420mm/16.5 in.
(f/16)

452mm/17.8 in.
(f/32)

452mm/17.8 in.
(f.32)


360mm/14.2in.
(f/16)


460mm/18 in.
(f/16)

Flange Focal Distance

312mm/
12.28 in.

542mm/
21.34 in.

733mm/
28.86 in.

270mm/
10.64 in.

367mm/
14.44 in.

Filter Size
77mm Screw in Front Cell
62mm Screw in Rear Cell
62mm Screw in Gold Ring
Location Bore in Lens Board
65mm Standard for Copal #3 Shutter

Overall Length
85mm / 3.35 inch (with Front + Back)

Weight
0.93 kg / 2.05 lbs (with Front + Back)

External Finish
Semi-gloss black anodised, with textured gold bevel ring.