Photogrammetric processing of a shaded valley floor

[SteveBCH]

I need to use my P4 RTK to fly and prepare a photogrammetric point cloud and orthophoto (using 3DSurvey) of the floor of a narrow valley that is fully shaded until about 9am. There are some tall trees and the shadows are getting rather long already even at high noon. With the P4 camera set to "Cloudy", is there enough light in the shade before the sun crests the ridge to get photos bright enough for photogrammetric processing? Thanks

 

[Meta4]

I need to use my P4 RTK to fly and prepare a photogrammetric point cloud and orthophoto (using 3DSurvey) of the floor of a narrow valley that is fully shaded until about 9am. There are some tall trees and the shadows are getting rather long already even at high noon. With the P4 camera set to "Cloudy", is there enough light in the shade before the sun crests the ridge to get photos bright enough for photogrammetric processing? Thanks

The way to deal with shadows is to shoot on an overcast day.

 

[Harleydude]

I need to use my P4 RTK to fly and prepare a photogrammetric point cloud and orthophoto (using 3DSurvey) of the floor of a narrow valley that is fully shaded until about 9am. There are some tall trees and the shadows are getting rather long already even at high noon. With the P4 camera set to "Cloudy", is there enough light in the shade before the sun crests the ridge to get photos bright enough for photogrammetric processing? Thanks

Set exposure manually. The histogram is your friend. I don't know how many stops of dynamic range the P4 camera has, but I would guess at least 10. The problem with auto exposure is it is dynamic (which creates inconsistent results) and it is based on overall lighting, not just the thing you're focused on. It's a real balancing act that requires diligence during flight.

D

 

[SteveBCH]

Set exposure manually. The histogram is your friend. I don't know how many stops of dynamic range the P4 camera has, but I would guess at least 10. The problem with auto exposure is it is dynamic (which creates inconsistent results) and it is based on overall lighting, not just the thing you're focused on. It's a real balancing act that requires diligence during flight.

D

Thank you.