Nikon D3100 2 manual 171, AF-Assist Illumination, Calculating Angle of View

Lens	Zoom position	Minimum distance without vignetting
AF-S VR Zoom-Nikkor 200–400mm f/4G IF-ED	250 mm	2.5 m/8 ft. 2in.
	350 mm	2.0 m/6 ft. 7 in.
	200 mm	5.0 m/16 ft. 5 in.
AF-S NIKKOR 200–400mm f/4G ED VR II	250 mm	3.0 m/9 ft. 10 in.
	300 mm	2.5 m/8 ft. 2 in.
	350–400 mm	No vignetting
PC-E NIKKOR 24mm f/3.5 ED *	24 mm	3.0 m/9 ft. 10 in.
* When not shifted or tilted.

When used with the AF-S NIKKOR 14–24mm f/2.8G ED, the flash will be unable to light the entire subject at all ranges.

DAF-Assist Illumination

AF-assist illumination is not available with the following lenses:

•AF-S NIKKOR 14–24mm f/2.8G ED

•AF-S NIKKOR 28–300mm f/3.5–5.6G ED VR

•AF-S DX NIKKOR 55–300mm f/4.5–5.6G ED VR

•AF-S VR Zoom-Nikkor 70–200mm f/2.8G IF-ED

•AF-S NIKKOR 70–200mm f/2.8G ED VR II

•AF-S Zoom-Nikkor 80–200mm f/2.8D IF-ED

•AF-S VR Nikkor 200mm f/2G IF-ED

•AF-S VR Zoom-Nikkor 200–400mm f/4G IF-ED

•AF-S NIKKOR 200–400mm f/4G ED VR II

At ranges under 1 m (3 ft. 3 in.), the following lenses may block the AF-assist illuminator and interfere with autofocus when lighting is poor:

•AF-S Zoom-Nikkor 17–35mm f/2.8D IF-ED

•AF-S DX Zoom-Nikkor 17–55mm f/2.8G IF-ED

•AF-S DX NIKKOR 18–105mm f/3.5–5.6G ED VR

•AF-S DX VR Zoom-Nikkor 18–200mm f/3.5–5.6G IF-ED

•AF-S DX NIKKOR 18–200mm f/3.5–5.6G ED VR II

•AF-S NIKKOR 24–70mm f/2.8G ED

•AF-S VR Zoom-Nikkor 24–120mm f/3.5–5.6G IF-ED

•AF-S NIKKOR 24–120mm f/4G ED VR

•AF-S Zoom-Nikkor 28–70mm f/2.8D IF-ED

•AF-S NIKKOR 85mm f/1.4G

•AF-S VR Micro-Nikkor 105mm f/2.8G IF-ED

ACalculating Angle of View

The size of the area exposed by a 35mm camera is 36 × 24 mm. The size of the area exposed by the D3100, in contrast, is 23.1 × 15.4 mm, meaning that the angle of view of a 35mm camera is approximately 1.5 times that of the D3100. The approximate focal length of lenses for the D3100 in 35mm format can be calculated by multiplying the focal length of the lens by about 1.5.

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

Lens Picture diagonal

Picture size (D3100) (23.1 × 15.4 mm)

Angle of view (35mm format)

Angle of view (D3100)

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