Operation at the ASTE site (2008-)
Operation at the ASTE site and Realtime data monitoring
- A sky image is automatically obtained every 5 minutes.
- Raw data for every single time consist of 7 images (FITS format) with a different brightness parameter of the infrared camera ("BR" = -10,0,4,8,12,16,20). The parameter "BR" gets larger, the camera gets more sensitive to the difference in less bright regions. We used the image of "BR"=-10 to determine the brightness level of the temperature standard, which is usually much brighter than the sky and clouds. Other six images (BR= 0 -- 20) are for the sky.
- A combined sky image was created by the control PC and is stored in FITS format. The brightness in the combined image is expressed by the "emissivity" of the sky.
- For realtime monitor of the sky during observations, a gif image is also created from the combied FITS by the control PC and is sent to the web server in Mitaka. The average and standard deviation of emissivity in each sky area are also calculated and shown on the web (see below: averages are shown in red, standard deviations are shown in blue).
Example of the monitor display on the web. The sky is divided into 12 areas; the boarder between the higher- and lower- elevation areas is located at about 60 degree in elevation.
Examples of Raw Data and combined images (2008/05/12)
- Below is an example of data taken on May 12nd 2008. It seems that it was cloudy before 03:00AM, but the cloud was gone after 03:00AM.
- The compressed raw data ("rawdata_20080512.afz")
- To uncompress the file, download it and then use the below command at your unix-base machine
- "afio –ivZ rawdata_20080512.afz "
- After uncompressing, you will find fits files of raw data in the directory "./data/fits/20080512/"
- The filename is like "ICMD_20080512_1200_-10.fits", which means the data taken at 12:00 of 2008May12nd with the brightness parameter=-10.
- The combined gif images ...
