Shad-o-Scan User Manual, Rev04
49
Shad-o-Scan 3001/4501 X-Ray Detector
Teledyne DALSA
Name
Description
Bits
Bytes
Endian
offset
Header Version
Version number of header
8
1
Big
0
File Type
0. Defectmap
1. Darkmap
2. Gainmap
8
1
Big
1
Serial Number
Serial number of the detector
128
16
Big
2
CRC
CRC of total data fle excluding the header
16
2
Little
18
Width
Number of columns in full resolution of the
detector
16
2
Big
20
Height
Number of rows in full resolution of the detector
16
2
Big
22
Image format
0. Full res
1. Binned 2x2
2. Binned 4x4
3. Binned 1x2
8
1
Big
24
FullWell
0. HFW
1. MFW
2. LFW
8
1
Big
25
File Format
1, 1bit per pixel
(for defect maps)
2, 2 bytes per pixel
(for gain and offset
maps)
8
1
Big
26
Division Factor Nominal value of gainmap as a power of 2.
A value of 15 means a division of 2 to the power
of 15
8
1
Big
27
Extra1
Reserved
16
2
Big
28
Extra2
Reserved
16
2
Big
30
Total
256
32
32
Example of Gain map header (hex format):
•
Gain map (offset 1, 02)
•
Serialnumber: 123456
•
Width: 1488 (offset 20, 05 D0)
•
Height: 1148 (offset 22, 04 7C)
•
Image format: 0: fullRes (offset 24, 00)
•
FullWell: 0 HFW (offset 25, 00)
•
FileFormat: 2 bytes per pixel (offset 26, 02)
•
Division factor: 2^12 = 4096 (offset 27, 0C)
•
Data: offset 32.
•
First data CF 0F represents a value of 4047 (0FCF) as the data is big endian
UINT16.
How to Create a New Gain Map
To use FFC to correct for system specific spatial intensity variations, new Gain maps
should be created and uploaded to the detector as part of the factory system
calibration routines.
For optimal gain correction, the Gain reference map should be created at an exposure
of approximately 25% of the full scale output signal.
To create a new Gain map:
•
Average at least 16 images captured by the detector, without any object
placed in the X-ray beam.
