Infrared Index of the Zoom Lens

When taking infrared photographs with the zoom lens, compensation in focus is necessary depending upon the focal length. The distance scale of the zoom lens has infrared indexes for each focal length.

Compensate for the focus according to the focal length in use (see page 9.).

 

50

 

20

ft

 

15

 

7

m

70

200

70

 

 

 

 

200

 

 

 

With lenses having indexes only for the longest and shortest focal length, such as FA Zoom 70-200mm, obtain the compensation value for intermediate focal length by using the scale as a guide.

28-105

ft

15 8

5

3

2

1.6

m∞ 5 3

2

1.2

0.7 0.5

The red line on the lens barrel of the FA28- 105mm f/4-5.6 (IF) is the infrared index line. Compensate for focus according to the focal length in use. See more details on page 9.

•The following lenses have no infrared index line.

FA Zoom 28-90mm f/3.5-5.6

FA Zoom 28-200mm f/3.8-5.6

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