Panasonic Lumix DMC-G6 Owner's Manual page 175

Recording
About the focus distance reference mark
The focus distance reference mark is a mark used to measure the focus distance.
Use this when taking pictures with Manual Focus or taking close-up pictures.
A Focus distance reference mark
B Focus distance reference line
C 0.2 m (0.66 feet) (Wide to focal length 20 mm)
[When the interchangeable lens (H-PS14042, H-FS1442A) is used]
D 0.3 m (0.98 feet) (focal length 21 mm to Tele)
[When the interchangeable lens (H-PS14042, H-FS1442A) is used]
E 0.3 m (0.98 feet) (Wide to focal length 21 mm)
[When the interchangeable lens (H-FS14140) is used]
F 0.5 m (1.6 feet) (focal length 22 mm to Tele)
[When the interchangeable lens (H-FS14140) is used]
G 0.3 m (0.98 feet) [When the interchangeable lens (H-FS014042) is used]
H 0.9 m (3.0 feet) [When the interchangeable lens (H-FS45150) is used]
Focus range
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