1st Observation Battery, 1922-1929
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75%
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Brightness:
-100
-90
-80
-70
-60
-50
-40
-30
-25
-20
-15
-10
-5
0
5
10
15
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25
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Contrast:
-100
-90
-80
-70
-60
-50
-40
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
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100
Grayscale