Page #1 - Main page with EXTA description

Page #2 - Measurements with analog video camera modul SK1004XC

Page #3 - Measurements with analog video camera WAT-902H2 Ultimate

Page #4 - Measurements with integrating analog video camera WAT-120N

Page #5 - Measurements with Astro CCD camera Atik 314L+ (this page)

Page #6 - Measurements with IOTA-VTI device

Page #7 - Measurements with integrating analog video camera MINTRON 12V1C-EX

EXTA measurement setup for Astro CCD camera Atik 314L+

The source for the FITS header time stamps was the capture software which used the PC system clock as reference. So it is very important to have the PC system clock synchronized to UTC with a very low offset. This can be accomplished with a good LAN or WLAN connection and a special time server software. Because a PC system clock is not long time stable the synchronisation should be repeated in time spans of minutes. To power on the system about 30 minutes before the first exposure start could prevent or reduce a big time drift caused by the warming up pc oszillator. So in this application it is very important that the two involved software packages, the capture software and the time server software, can handle the time with a high accuracy.

All the Atik 314L+ CCD images below were scaled down to the half size for a better fit in browser windows. The PC system clock was hold within 50ms to UTC and the FITS header times are allocated to the exposure start times. FITS header times are given by the capture software with a resolution of 100ms.

Atik 314L+ CCD image with exposure duration set to 500ms

EXTA LED step time = 1ms, FITS header time = 20:46:32.8 UTC

Real exposure time = 20:46:32.870 - 20:46:33.393 UTC (Duration 523ms)

Atik 314L+ CCD image with exposure duration set to 1s

EXTA LED step time = 2ms, FITS header time = 20:43:14.5 UTC

Real exposure time = 20:43:14.568 - 20:43:15.614 UTC (Duration 1.046s)

Atik 314L+ CCD image with exposure duration set to 2s

EXTA LED step time = 5ms, FITS header time = 20:39:25.5 UTC

Real exposure time = 20:39:25.570 - 20:39:27.660 UTC (Duration 2.090s)

Atik 314L+ CCD image with exposure duration set to 5s

EXTA LED step time = 10ms, FITS header time = 20:49:43.1 UTC

Real exposure time = 20:49:43.110 - 20:49:48.190 UTC (Duration 5.080s)

Atik 314L+ CCD image with exposure duration set to 10s

EXTA LED step time = 20ms, FITS header time = 20:55:58.0 UTC

Real exposure time = 20:55:58.020 - 20:56:08.100 UTC (Duration 10.080s)

Atik 314L+ CCD image with exposure duration set to 30s

EXTA LED step time = 50ms, FITS header time = 21:06:53.9 UTC

Real exposure time = 21:06:53.900 - 21:07:24.000 UTC (Duration 30.100s)

Atik 314L+ CCD image with exposure duration set to 45s

EXTA LED step time = 50ms, FITS header time = 21:23:53.0 UTC

Real exposure time = 21:23:53.000 - 21:24:38.100 UTC (Duration 45.100s)

Pages of the EXTA project

Page #1 - Main page with EXTA description

Page #2 - Measurements with analog video camera modul SK1004XC

Page #3 - Measurements with analog video camera WAT-902H2 Ultimate

Page #4 - Measurements with integrating analog video camera WAT-120N

Page #5 - Measurements with Astro CCD camera Atik 314L+ (this page)

Page #6 - Measurements with IOTA-VTI device

Page #7 - Measurements with integrating analog video camera MINTRON 12V1C-EX

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