TriCCS is open in shared risk in the 2021B-2022A semesters.
Some stray light was detected. Its strength and shape vary as the telescope moves.
Images after the flat-field correction may have sky non-uniformity of ~10%. It degrades the limiting magnitudes or produces a false detection of diffuse sources.
z-band filter was not tested well. There may be some problems we don't recognize.
# Limitations
The available filter sets are "g, r, i-bands" and "g, r, z-bands." Observers can switch the filter set with remote access.
The maximum data rate is one frame per second for object frames in the 2021B semester. Observers are allowed to take dark and flat frames at a higher data rate.
# Recommendations
Observers should take flat frames using twilight in sunset or sunrise to collect the non-uniformity of throughput in optics and detector pixels.
To subtract the dark current pattern in CMOS sensors, observers should take dark frames with the shutter closed. The dark pattern varies depending on the exposure time and the CMOS gain. We recommend obtaining about the same total exposure time of dark frames as object frames at one field.
We advise observers to take not a single long exposure frame but multiple 10- to 30-second exposure frames for obtaining deep images. TriCCS frames saturate in a short exposure time by sky background due to the small output depth, 14-bit. Observers can reject frames affected by cosmic rays or other unexpected noises in data reduction.
TriCCS produces enormous data in the fast mode. The data amount of a 10-fps 8-hour observation is 5.2 TB, and it takes about 7 hours to copy it to a hard disk drive.