1. All the plotted data and images are just for browsing purpose and
are not fully calibrated. Please do not use the data at any
presentations and publications without contacting the Principal
Investigators, K. Shiokawa (shiokawa at stelab.nagoya-u.ac.jp).
2. Digital data are available on request. Please contact the Principal
Investigator to copy the data. The Principal Investigator
may limit the use of the data in order to avoid possible confliction of
the scientific directions of the users.
3. The all-sky image data at Rikubetsu (camera 3 after October, 1998) is
upside down (upward is toward the south) for October 20, 1998 - March 31,
1999. Please see figure captions.
4. For the SATI data, the values of temperature may be corrected in the
future by using new calibration data sets. Please also see the background
level in the plots. High background means cloudy sky during which the
temperature and intensity data become meaningless.
5. Please refer Shiokawa et al.  for details of the instrumentation.
**************** some additional local notes *******
1. Camera A (10) at Paratunka was stopped for March 5-11, 2008,
due to condensation in the lens system after severe cyclone
on February 28, 2008. The lens was cleaned on August 16-17, 2008.
2. The CCD temperature of FP01 at Tromso raised from -80C (normal)
to ~-65C at Feb.16-Mar.11, 2010 due to water flow degradation.
So the 630-nm temperature data may be affected.
3. The FPI04 at Darwin has scanning problem. The sky scanner does
not move for May 21-July 7, 2011, due to missing the position
4. The Camera #11 (Camera B) at Magadan has a problem of A/D converter
of CCD since early 2014. We make fast-scan measurements since April 2015.
The sensitivity becomes ~1/16.5 from slow scan to fast scan, and
the satulation level becomes from 65535 counts to 4096 counts.
5. The Camera #10 (camera A) at Paratunka was repaired due to CCD cooler
trouble and restarted the observation from 16 June 2015.
6. In Dec 25, 2017, we found a problem on the timing recorded on the
filename of the OMTI all-sky imagers for PTK, MGD, ERK, KAP, NYR,
GAK, IST, and HUS. The time in the filename can be incorrect for
some data. Details are shown in this file.
This problem has already been fixed for most of the stations by
Dec. 30, 2017. When you use the 2017 data of these imagers, please
be careful on the timing. Please feel free to contact us if you
have any questions on the timing delay of each station.
7. From December 16, 2015 to March 17, 2018, the sky-scan direction of the
Fabry-Perot interferometer at Darwin (FP04) is 7.5 degree shifted from
north-south (N-S) and east-west (E-W) to NNE-SSW and ESE-WNW.
This is due to the wrong setting of home position of the azimuth-scan
motor of the FPI skyscanner for 7.5degree.
8. On April 19, 2018, we noticed that the router/IP setup of the FPI
PC was incorrect, causing the NTP automatic time correction was not
working. The time difference from the correct time was 289.567s
delayed from the correct time on April 19, 2018.
9. For Istok, GPS synchronization seems to be failed. It was found on
March 5, 2019. The PC clock of the imager is ~1 minute different from
correct time. This error was corrected at 06 UT on March 5, 2019.
This error may be caused at the power failure on September 20, 2018.