Panasonic LUMIX DMC-GM1 Operating Instructions For Advanced Features page 152

6. Focus and Brightness (Exposure) Settings
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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) (focal length 12 mm to 20 mm)
[When the interchangeable lens (H-FS12032) is used]
D 0.3 m (0.98 feet) (focal length 21 mm to 32 mm)
[When the interchangeable lens (H-FS12032) is used]
E 0.2 m (0.66 feet) [When the interchangeable lens (H-H020A) is used]
Focus range
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