QHY174M-GPS has a unique GPS based Precision Time function for star eclipse, meteor discovery, UFO recording and any other scientific exploring things which require extremely high time base.

• QHY174 has dual stage TEC cooling, -45C below ambient and fully anti-moisture functions which includes the CMOS optic window heater, and the removable silicon tube for CMOS chamber dry control.
• QHY174 has the 4pin QHYCFW2 filter wheel control port and 6pin autoguide port.
• QHY174 and an anti-amp glow function. It can reduce the IMX174 sensor's amplifier glow significantly in long exposure.

The most interesting thing is the QHY174's optional Precision-time functions. It allows two QHY174s to have the same time base up to microseconds at anywhere in the world.

QHY174 will record the global shutter exposure starting and ending time in microsecond precision. The time base is synced to the GPS timing which is highly accurate. To guarantee the physical exposure starting and ending time, QHY174M-GPS has a built-in LED pulse calibration circuit in 1 microsecond (us) precision.

This function is available in the form of a small optional GPS module for QHY174M. This module is tiny and is pre-installed inside the camera for QHY174M-GPS version.

Two working mode 

Master mode: The camera is free running and the internal 10MHz GPS synced clock will measure the shutter open and close time.

Slave mode: You can input a target start time and the interval period of two frames. For example: You want three cameras in different position (maybe thousands of kilometer) to start exposure at 2016.3.9.UTC 14:00:00.000000 and the interval time is 0.100000sec.

After you input this value. All the three cameras will wait till this time and start video recording. The exposure time should be

2016.3.9 UTC 14:00:00.000033

2016.3.9 UTC 14:00:00.100033

2016.3.9 UTC 14:00:00.200033

2016.3.9 UTC 14:00:00.300033

(The 0.00033 is a global delay of the CMOS shutter).