Picture Angle and Focal Length

A 35-mm camera has a diagonal picture angle approximately one-and-a-half times that of the D70. When calculating the focal length of lenses for the D70 in 35-mm format, you will therefore need to multiply the focal length of the lens by 1.5, as shown in the following table:

 

 

 

Approximate focal length (mm) in 35-mm format

 

 

 

Picture angle

 

 

(modified for picture angle)

 

 

 

35-mm film camera

17

20

24

28

35

50

60

85

 

 

D70

25.5

30

36

42

52.5

75

90

127.5

 

 

 

 

 

 

 

 

 

 

 

35-mm film camera

105

135

180

200

300

400

500

600

 

 

D70

157.5

202.5

270

300

450

600

750

900

 

Technical Notes—Optional Accessories

Calculating Picture Angle

The size of the area exposed by a 35-mm

 

camera is 36 × 24 mm. The size of the

 

area exposed by the D70, in contrast,

Lens

is 23.7 ×15.6 mm. As a result, the picture

 

angle of photographs taken with the D70

 

differs from the picture angle for 35-mm

 

cameras, even when the focal length of

 

the lens and the distance to the subject

 

are the same.

 

Picture size (35-mm format) (36 mm 24 mm)

Picture diagonal

Picture size (D70) (23.7 mm 15.6 mm)

Picture angle (35-mm format)

Picture angle (D70)

185

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Image 195
Nikon D70 manual Picture Angle and Focal Length, 185, Calculating Picture Angle