Experimental aerial photogrammetry with professional non metric camera Canon

EOS 5D

Galileo Geo SustaviAnte Sladojević, Goran Mrvoš

Content

• Introduction• Project Specification• Camera Calibration• Flight plan• Aerotriangulation• Creating DEM and digital orthophoto• Conclusion

Introduction

• Test professional non metric camera• Aerial photogrammetry purpose• Will it work in aerial photogrammetry?• Reliability?• Accuracy?

Project specification - equipment

• Camera Canon EOS 5D• Sensor type • 35.8 x 23.9 mm CMOS

• 12.8 million effective pixels • Image size: • 4368 x 2912 pix• Dimensions: • 152 x 113 x 75 mm

• Wide angle lens (24mm)• Camera box and carrier• Airplane Cessna 172 Rocket• PHOTOMOD 4.1

Project specification - work flow

• Camera calibration• Making flight plan• Flying and taking images of selected area • Loading images in photomod,

aerotriangulation• Creation of DEM and digital orthophoto• Analyzing results

Camera Calibration

• Lens (24mm)• Characteristics of a camera (focal length, lens

distortion) • Used software PhotoModeler pro 5.0. • 2D dimensions calibration grid• Results of camera calibration:

• Focal Length - Value: 23.811862 mm• Principal point (Xp, Yp)

• (17.311063 mm, 11.615114 mm) • Radial distortion (K1, K2 ,K3)• Decentering distortion (P1, P2)

Flight plan

• Area = 2.2 km long (city highway)

• Two strips (52 images)

• Base 120 m (60%)

• Distance between strips 310 m (30%)

• Flying height (300m)

• Scale 1:12500

• Navigation with Garmin GPS

Aerotriangulation

• PHOTOMOD 4.1 (default configuration)

• Automatic aerotriangulation (1272 tie points)

• Correlation (>0.94, parallax <0.010 mm)

• 10 GCP, 4 beginning and the end of the strips, 2 in the middle of the strips

• GCP residuals• Xm-Xg Ym-Yg Zm-Zg Exy (m)• mean absolute 0.038 0.045 0.160 0.062 • RMS 0.046 0.053 0.184 0.070 • Maximum 0.087 0.102 0.316 0.134

Creating DEM and digital orthophoto

• DEM (1m) • Vectors and breaklines (Stereo Restitution, PHOTOMOD StereoDraw)• Digital othophoto (PHOTOMOD Mosaic)• Geometric resolution (0.1m) • Digital orthophoto control:

• Overlap with exisiting data

• The results were very good - max overlap error was 0.4 m.

Conclusion

• Good accuracy

• Large number of images for small areas (1 km=10 images)

• Not good for large areas (time)

• Digital non metric camera are getting better and better (16 Mpix, 32 Mpix)

• Better accuracy's

• Better resolution (good calibration)

Thank you for your attention !

• Questions?