QHY990/QHY991/QHY992 SWIR Cameras

Gain0：-50 – +10 Dark Current

QHY992

Before using software, make sure you have connected the cooling camera to the 12V power supply and connected it to the computer with a USB3.0 data cable. If it’s an uncooled camera, 12V power is not needed. We recommend 64-bit Software, like SharpCAP x64 , N.I.N.A x64. etc., especially when you’re using 16bit cameras.

Launch SharpCap. If the software and drivers mentioned above are installed successfully, the video image will appear automatically about 3 seconds after the software loads. You will also see the frame rate in the lower left corner of the software window as shown below.

If you have already started the SharpCap software before connecting the camera, in order to open the camera, click on the “camera” in the menu bar and then select the device.

Offset adjustment. When you completely block the camera (i.e., like taking a dark frame) you may find that the image is not really zero. Sometimes this will reduce the quality of the image contrast. You can get a better dark field by adjusting the offset. You can confirm this by opening the histogram as indicated in the figure below.

If you want to enter the 16-bit image mode, select the “RAW16” mode.

By selecting the “LX” mode you can expand the exposure setting range and take long exposures.

After cooling devices connected to the 12V power supply, the temperature control circuit will be activated. You can control the CMOS temperature by adjusting the settings in the figure below. Basically, you can control the temperature of CMOS by either adjusting “Cooler Power” or clicking “Auto” and setting “Target Temperature”. You can also see the CMOS temperature at the lower-left corner of the software window.

1. There are holes in the two sides of the camera near the front plate that is normally plugged by a screw with an o-ring. If there’s moisture in the CMOS chamber that causes fog, you can connect the desiccant tube to this hole for drying. There would better be some cotton inside to prevent the desiccants from entering the CMOS chamber.Please note that you may need to prepare desiccants yourself, because for most countries and regions desiccants are prohibited by air transport. Since QHY always deliver your goods by air, sorry that we can’t provide desiccants for you directly.
2. Cyclic Drying: The front end of the camera body is equipped with two drying interfaces with M5 threads, which are used in conjunction with drying tubes and circulation pumps for drying treatment inside the sensor chamber. The position of the drying interface is indicated by the red circle in the figure below (take the QHY600 as an example):Under the vacuum pump, the gas inside the sensor chamber is drawn out through one drying interface, enters the drying tube, and then undergoes filtration. It is then reintroduced into the camera through the other drying interface, circulating back and forth for drying.

   Note:1.Do not reverse the order of the intake and exhaust ports

   2.Before circulating drying, it is necessary to turn off the refrigerator, and then turn on circulating drying after the temperature returns to normal temperature. Only by following this step can the water vapor in the sealed chamber be effectively removed. If the cooler is turned on, the cooler inside the camera will absorb water vapor, causing more water vapor to condense inside the camera instead of being absorbed by the desiccant.

If you find dust on the CMOS sensor, you can first unscrew the front plate of the cam and then clean the CMOS sensor with a cleaning kit for SLR camera sensors. Because the CMOS sensor has an AR (or AR/IR) coating, you need to be careful when cleaning. This coating can scratch easily so you should not use excessive force when cleaning dust from its surface.

All QHY cooling cameras have built-in heating plates to prevent fogging. However, If the ambient humidity is very high, the optical window of the CMOS chamber may have condensation issues. Then try the following:

1. Avoid directing the camera towards the ground. The density of cold air is greater than of hot air. If the camera is facing down, cold air will be more accessible to the glass, causing it to cool down and fog.

2. Slightly increase the temperature of the CMOS sensor .

3. Check if the heating plate is normally working. If the heating plate is not working, the glass will be very easy to fog, the temperature of the heating plate can reach 65-70 °C in the environment of 25 °C. If it does not reach this, the heating plate may be damaged. Please contact us for maintenance.

Please avoid thermal shock during use. Thermal shock refers to the internal stress that the TE cooler has to withstand due to the thermal expansion and contraction when the temperature of the TEC suddenly rises or falls. Thermal shock may shorten the life of the TEC or even damage it.

Therefore, when you start using the TEC to adjust the CMOS temperature, you should gradually increase the TEC power rather than turning the TEC to maximum power. If the power of the TEC is high before disconnecting the power supply, you should also gradually reduce the power of the TEC and then disconnect the power supply.

Under normal circumstances, the frame rate of a CMOS camera will increase accordingly after reducing the exposure time, but the Sony IMX990/991 chip supports two modes.

In the first mode, when the exposure time is lower than the reciprocal of the frame rate, two different background biases will be generated, and the boundary position will change up and down with the exposure time setting.

In the second mode, when the exposure time is less than QHY990 (15ms) 991 (8ms), the frame rate will no longer increase. This mode can avoid the generation of two different background biases in the image.

The modification mode can be installed in QHYSDK and executed as follows: