I had tested some indoor photogrammetry for 3D reconstruction of a square section artificial stream in an urban scenario.
It was 2 meters heigh, 4 meters wide and 10 meter long.
It was a test.
So i tested my stuff.
I tested 360° cameras and also full frame DSLR.
In order to have good quality pictures from my FX camera to be processed with Structure from Motion i needed to light the hole.
It was not pitch black, but it was dark.
And it was cloudy too.
There was little space and light should have been even distributed over the area in each pictures.
Camera was moving so light had to follow it.
I decided to build a DIY (Do It Yourself) system mad by:
- photographic tripod with ball head;
- full frame DSLR camera (Nikon D800) with 24mm lens;
- 500Ws battery flash (Profoto B1);
- bracket and tilting joint to adjust the position of the camera and flash;
- remote shutter release cable;
- external exposure meter to control the exposure of the scenes illuminated by the flash;
- laser distance meter to check the measurements to be respected in order to have right overlap between pictures.
I moved the camera back and forth the tunnel in order to photograph right and left side, ceiling and floor.
Flash light was bounced back to the wall opposite to the camera, and was able to cover the whole surface in each frame step by step.
With nice soft light.
It was not fast and a little bit tricky too.
I made it with the equipment i had.
It was nice!
Most important, i reached the goal to have well lit pictures, taken with good depth of field and low ISO.
Many thanks to David Umberto Zappa of Duzimage for the technical support in setting up the “system”.