CALIBRATION REPORT SUMMARY

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2 CALIBRATION REPORT SUMMARY Material Description Assembly 2PADI A / 09A Camera Module 1 CCD KODAK KAF 39Mp Full Frame Color Image Sensor SN CQ Lens Schneider Apo Digitar 4.0/80 N SN Shutter Rollei Electronic Shutter size 0 SN Camera Module 2 CCD KODAK KAF 39Mp Full Frame Color Image Sensor SN CQ Lens Schneider Apo Digitar 4.0/80 N SN Shutter Rollei Electronic Shutter size 0 SN Image Characteristics Image Process Development of RAW images in CaptureONE v4 and upper Image Size Across flight line 10,300 pixels Along flight line 7,150 pixels Across flight line Along flight line mm mm Pixel Size 6.8 µm Focal Length mm Principal Point of X = mm Autocollimation Y = mm Principal Point of X = mm Symmetry Y = mm Referring to image native orientation as imposed through DiMERGE processing (with X axis opposed to flight direction). For other image orientations see illustrations and values in pages 3 and 4. Distortion Not applicable Already corrected within merging process DiMAC sprl Calibration Report 1/14

3 CALIBRATION REPORT STRUCTURE While the information required to perform the post treatment of the DiMAC images is summarized into the first section of this document (see page 1), this report aim to define the whole process undertaken by DIMAC to determine the calibration of a DiMAC. As each user presents specific preferences and constraints on image orientation, the four image orientations and impacted calibration characteristics are described in pages 3 and 4. Secondly, the technical characteristics of the single image acquisition device are presented in page 5. Thirdly, the methodology used by DIMAC to realize the geometric calibration of its camera module is thoroughly explained (see page 6 8). Then, the radiometric calibration principles are described in pages 9 to 13. The document ends with certification agreement from DiMAC calibration authorities (see page 14). DiMAC sprl Calibration Report 2/14

4 IMAGE COORDINATE SYSTEM ROTATION ILLUSTRATION Orientation 1 Orientation 2 Rotation 0 Rotation 90 clockwise Y Y PPA X X PPA PPA Flight direction Flight direction Orientation 4 Orientation 3 Rotation 270 clockwise Rotation 180 clockwise Y Y PPA X PPA X PPA Flight direction Flight direction DiMAC sprl Calibration Report 3/14

5 IMAGE CHARACTERISTICS Image Orientation Orientation 1 Orientation 2 Orientation 3 Orientation 4 Orientation Definition Clockwise rotation from native Flight Direction To left To up To right To down Image Size Height [pxl] 10,300 7,150 10,300 7,150 Width [pxl] 7,150 10,300 7,150 10,300 Height [mm] Width [mm] Principal Point of Autocollimation X [mm] Y [mm] Principal Point of Symmetry X [mm] Y [mm] DiMAC sprl Calibration Report 4/14

6 SINGLE IMAGE TECHNICAL CHARACTERISTICS CDD SPECIFICATIONS The light sensitive unit used by DiMAC is a Dalsa Area Bayer RGB Charge Coupled Device (CCD) with to the following characteristics: - Number of Active Pixels: 7,216 (H) x 5,412 (V) - Pixel Size: 6.8 µm (H) x 6.8 µm (V) - Active Image Size: mm (H) x mm (V) - Aspect Ratio: 4:3 - Radiometric Resolution: 16 bits per color channel True color images generation is based on the Bayer Filter principle allowing direct measurement of incoming light in each true color bands (red, green and blue) as each CCD sub element is only sensitive to one of the three bands. MODULAR TRANSFER FUNCTIONS The light modulation due to lens cross is not constant from the lens centre to the edge, but also depends of aperture and line discrimination resolution. The light modulation from lens centre to lens edge is presented in the following figures as a function of aperture: k=4.0 (1), k=5.6 (2) and k=8.0 (3). Source: Jos. Schneider Optische Werke GmbH, Ringstrasse 132, Bad Kreuznach, Germany DiMAC sprl Calibration Report 5/14

7 GEOMETRIC CALIBRATION DIMAC bases the calibration of its camera on a set of eighteen images per camera module of a defined geometry target including 275 control points and multiple lines. This is the DiMAC Lab Calibration Site (DiLCS), which is used to define the three parameters linked to the imagery: the focal length, the image centre and the distortion values of each camera module. In addition, the DiLCS enables to establish the relative position of each camera module from a DiMerge pair, which ultimately allows DiMerge to merge two specific camera modules to reach a rectangular, perpendicular and flatness re composed image. The DiLCS is built in a way to offer planimetry as well as 3D views. During the calibration process, eighteen pairs of images are produced: six image orientation at three positions. DiMAC sprl Calibration Report 6/14

8 THREE POSITIONS The first position acquired corresponds to a visualization of the flat part, which is in principal used for distortion determination. The second and third positions provide larger views of the DiLCS but at two different scales and enables 3D information used for focal length and image s centre definition. First position Second position Third position DiMAC sprl Calibration Report 7/14

9 SIX ORIENTATIONS At each position, a set of six images are taken corresponding to six different orientations: centre, right, left, up, down and centre again but rotating the camera block of 180 degree. Those six images allow reproducing the plane surface variation and its consequences on image point location. TARGETS AND LINES In addition to the 275 targets, the DiLCS also contains vertical and horizontal lines meant to help defining the distortion of each camera module as well as its geometric position towards its associated camera module. Each target has a principal point of control (see red square), which corresponds to its centre as well as 4 secondary points of control (see black square) that is located at each side of the target. As this principle is applied to six images at three positions, no less 24,750 points of measurement per camera are used to define the geometric calibration parameters. DiMAC sprl Calibration Report 8/14

10 RADIOMETRIC CALIBRATION For each relevant standard aperture and for each delivered filter (RGB and NIR), an image of a flat white panel exposed under a known standardized light intensity is captured. As such, the camera module has gone through the following aperture: f stop Based on those images, a Lens Cast Correction (LCC) will be defined for each relevant camera settings, which will be applied during development process. Based on those pre settings, each camera module image will have a color profile applied every time a development of images will occur. Following this step, DiMerge will reconstruct a merged image where it will apply a radiometric balance taking into account the overall radiometric specifications of a given set of exposures. This balance is by default a mean calculation between radiometric values of both exposures, but it can focus on one sensor rather than another according to the exposure conditions. DiMAC sprl Calibration Report 9/14

11 CAMERA MODULE 1 CCD KODAK KAF 39Mp Full Frame Color Image Sensor SN CQ Lens Schneider Apo Digitar 4.0/80 N SN Shutter Rollei Electronic Shutter size 0 SN f stop Checked DiMAC sprl Calibration Report 10/14

12 APERTURE SETTING DiMAC sprl Calibration Report 11/14

13 CAMERA MODULE 2 CCD KODAK KAF 39Mp Full Frame Color Image Sensor SN CQ Lens Schneider Apo Digitar 4.0/80 N SN Shutter Rollei Electronic Shutter size 0 SN f stop Checked DiMAC sprl Calibration Report 12/14

14 APERTURE SETTING DiMAC sprl Calibration Report 13/14

15 CERTIFICATION Manufacturer Camera Module 1 Camera Module 2 Assembly Calibration Revision Calibration Reference DiMAC sprl Charleroi Airport, South Terminal Rue des Fusillés, Building S13 B 6041 Gosselies, Belgium CQ CQ A R6W C4B14D4v50 Calibration Date August 25 th 2010 DiMAC recognizes that the sub mentioned camera module is being in a serviceable condition and certifies its geometric and radiometric quality as defined above. FOR CERTIFICATION François COLLETTE Julien LOSSEAU Data Integration Engineer DiMAC sprl Managing Director DiMAC sprl DiMAC sprl Calibration Report 14/14