Video camera compare test images
Star cluster M67

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This page contains links to more than 100 real sky images captured from as many video sequences for direct comparison of seven different video cameras. Some of this video cameras were kindly lent to me by Dr. David Dunham from USA, Dr. Terrence R. Redding from USA and Olivier Thizy from France. Without this additional cameras this extensive sensitivity comparison recordings and other timing measurements would not have been possible. Therefore, I want to thank all for the great support and the patience because of the long delay mainly caused by bad weather situation here in Austria.

All test recordings were made in the same night on March 04, 2013 under very good, stable and unchanging sky conditions in Nonndorf, MPC C47. The elevation of the recorded object M67 was always 40 degree above the local horizon. Star cluster M67 is located in constellation Cancer at position RA 08h51m18s, DEC +11° 48´ 59". The used telescope system was a 1200/254mm (f/4.72) Newton, mounted on a motor driven equatorial mount. To avoid any system caused wavelength influence no coma corrector was used. Due to the small video CCD sizes coma is not a problem. So no glass and no filter affected the optical path. A sky brightness measurement in zenith with a SQM-L showed a stable value of +21.2mag/sqas or +6.2mag visual limit in this night. The ambient temperature was in the range of -5° Celisus or 268 Kelvin. So the majority of thermal image noise was surely caused by self-heating of the not self cooled cameras.

The used analog video converter was an external USB video grabber DFG/USB2-lt device from "The Imaging Source". The digitized video was recorded direct to a Notebook HD in AVI container format and with the lossless and non-compressing B/W video codec Y800. The Y800 codec stores only the luminance value as one byte for every pixel. The software VirtualDub was used for video recording. Because of the two different video systems used by the tested video cameras, the image sample size was set to 768x576 for CCIR and 640x480 for EIA to create always a final video format with the same 4:3 ratio as primary optical exposured by the CCD video sensors.

All images presented on this page are single frames in original state captured with VirtualDub from the video file without any further image processing. No darks, flats or bias were used. The color cameras were set to work in permanent B/W mode. But we have to consider that color cameras always have a Bayer matrix filter mounted in front of the CCD. The cameras were all set to Gamma=1 to work with linear characteristic. And all possible image changing features in the cameras were deactivated. Only exposure time and signal gain of the cameras was changed between the recording sequences in this night.

Tested video cameras

Type	Signal / System	Color or B/W	Integration feature	Sensor size - Type	FOV with FL=1200mm
WAT-910HX/RC	Analog / CCIR	B/W	Yes	6.4x4.8mm - Type 1/2"	18.3 x 13.7 arcmin
WAT-120N	Analog / CCIR	B/W	Yes	6.4x4.8mm - Type 1/2"	18.3 x 13.7 arcmin
PC165DNR	Analog / EIA	Color and B/W set to B/W	Yes	4.8x3.6mm - Type 1/3"	13.7 x 10.3 arcmin
SCB-2000N	Analog / EIA	Color and B/W set to B/W	Yes	4.8x3.6mm - Type 1/3"	13.7 x 10.3 arcmin
WAT-902H2 Ultimate	Analog / CCIR	B/W	No	6.4x4.8mm - Type 1/2"	18.3 x 13.7 arcmin
PC164C-EX2	Analog / EIA	B/W	No	4.8x3.6mm - Type 1/3"	13.7 x 10.3 arcmin
DMK21AU618	Digital - USB	B/W	Yes	3.6x2.7mm - Type 1/4"	10.3 x 7.7 arcmin

Left click to select captured video image and open it in a new browser window
Right click to select captured video image and download it as a gif file to your local drive

Guide reference star maps of star cluster M67 with stars shown in real spectral colour
FOV of Type 1/2" CCD		FOV of Type 1/2" CCD + mag values