Nikon D6 Reference Manual page 371

Option
•
[Add]: The exposures are overlaid without
modification; gain is not adjusted.
•
[Average]: Gain is adjusted before the exposures are
overlaid.
- The gain for each exposure is equal to 1 divided by
the total number of exposures taken. For example, in
a photo made by combining two exposures, the gain
for each exposure will be set to
combining three exposures, gain will be set to
•
[Lighten]: The camera compares the pixels in each
exposure and uses only the brightest.
[Overlay
mode]
•
[Darken]: The camera compares the pixels in each
exposure and uses only the darkest.
Combining Multiple Exposures in a Single Photo (Multiple Exposure)
Description
1
/ , while in a photo
2
1
/ .
3
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