The QHY174GPS camera uses the 1/1.2-inch SONY IMX174 CMOS sensor with global shutter, 5.86um pixels,138FPS@1920*1200, high QE of 78%, and low read noise of 3-5e-. It is useful for imaging occultations, eclipses, meteors, and other scientific imaging requiring a highly precise recording of the time and location of the observation on every frame.

The QHY174GPS has a unique built-in GPS module that can sync with the atomic clock signals received from GPS satellites.  The QHY174GPS can record the start and end of exposure time with 1us precision anywhere on earth. The QHY174GPS was selected by the NASA New Horizons Team to successfully captured the MU69 occultation in the Summer of 2017. The QHY174M-GPS has dual stage TE cooling to -45C below ambient with full anti-moisture control including heated optical window and removable desiccant plug for the sensor chamber. The QHY174 also has an anti-amp glow function.  It can reduce the IMX174 sensor’s amplifier glow significantly in long exposures.

The QHY174M-GPS records the global shutter exposure starting and ending time with microsecond precision.  Two QHY174 cameras, for example, each located anywhere in the world, can have the same time base, accurate to microseconds.  In order to guarantee the starting and ending time of the exposure, the QHY174 has a built-in LED pulse calibration circuit precise to 1 microsecond.

Master mode:  In Master Mode, the camera is free running and the internal 10MHz GPS synced clock will measure and record the shutter’s opening and closing time.

Slave mode:  In Slave Mode you can input a target start time and the interval period for two frames. For example: You want three cameras in different locations (maybe thousands of kilometers apart) to start an exposure at 2016.3.9.UTC 14:00:00.000000 and then to continue with exposures at the interval time of 0.100000 sec.  After you input these value, all the three cameras will wait until this time and then simultaneously start video recording, e.g.:

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).

The time stamp and other GPS information is embedded into the image. The software decodes it in real time and displays the information on left.  Since the data is embedded, it will never be lost so long as you keep the original image.