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.

The instructions below are based on SharpCap 3.1

• Launch SharpCap.

Click Camera in the menu bar and select your camera.

If the software and drivers mentioned above have been installed correctly, the image will appear automatically. And the frame rate can also be seen in the lower-left corner of the software window, as shown below.

• Main Interface Functions:

Capture Profiles
Preset management.
After SharpCap is restarted, the default settings are restored. If you frequently use one or more specific parameter configurations, you can adjust the parameters as needed and then click Save to store them as a preset. The preset can be directly recalled the next time you open the software.

Exposure
Sets the exposure duration. When LX Mode is enabled, the single-frame exposure time can be extended to longer values.

Gain
Equivalent to the ISO setting on a standard digital camera. Higher gain values result in higher sensitivity.

Frame Rate Limit
Limits the maximum frame rate. By default, no limit is applied. Users can set the limit manually if needed.

Offset
Adjusts the bias level. Even when the camera is completely covered, the image may not appear perfectly black. By adjusting the offset value, a more optimal dark frame can be achieved. The Histogram can be used to verify the adjustment.

USB Traffic
Controls the data transfer speed (frame rate). When set to 0, the camera operates at its maximum frame rate.

Enable Broadcast Mode
Enables the broadcast driver. For detailed usage instructions, please refer to the documentation available on the download page.

Read Mode
Some camera models support high-gain and low-gain readout modes.

Color Space
Select the output format.
Raw8 / Raw16 are 8-bit or 16-bit formats. Images and videos saved in Raw8 or Raw16 format will be monochrome, even when using a color sensor. Color information must be restored through debayering during post-processing.
RGB24 is a non-RAW format that outputs color images directly, but requires more storage space.

Capture Area
Select the resolution used for image capture.

Binning
Enable pixel binning for image capture.

Output Format
Select the output file format.

Debayer Preview
When this function is enabled, the live preview will be displayed in color even if a RAW format is selected. Please note that the saved images will still be monochrome.

Gamma, Brightness, Contrast
Under normal operating conditions, we recommend leaving these settings unchanged.

White Balance (R/G/B)
This function is used for white balance calibration on color cameras. For detailed calibration instructions, please refer to the corresponding section on the color camera page.
This function is not required for monochrome cameras.

Histogram
The histogram is an important image reference tool. It can be used to check whether the white balance is set correctly, whether the offset value is appropriate, and whether the image is overexposed.
Its operating principle is the same as that of the histogram used in standard DSLR cameras.

Thermal Controls
After the cooled camera is connected to a 12 V power supply, the temperature control circuit will be activated. You can control the CMOS sensor temperature by adjusting the settings shown below.

There are two main methods for temperature control:

Adjusting the cooler power
Setting a target temperature

If you wish to control the CMOS temperature by setting a target temperature, first click “Auto”, and then use the slider to set the desired target temperature.

Scope Control: for filter wheel control
Select the corresponding filter wheel slot to control the rotation.

Note: The software must be started after the filter wheel has completed its rotation and returned to the home position; otherwise, the position will not be displayed correctly.

QHY devices can operate with many software applications that support the ASCOM platform. MAXIM DL is used as an example below.

First, make sure that both the ASCOM platform and the QHY ASCOM driver have been successfully installed. Launch MAXIM DL and follow the instructions shown in the figure below to complete the setup.

Click “Connect”

Set the cooling temperature.

EZCAP_QT is software developed by QHYCCD. For QHYCCD cameras, it provides basic image capture functions.

Install the EZCAP_QT software and connect the camera to your computer using a USB 3.0 cable. Launch EZCAP_QT, then click “Connect” under Menu → Camera.
If the camera is successfully connected, the EZCAP_QT title bar will display the camera firmware version and camera ID, as shown in the figure below.

In Camera Setup, click Temp Control to set the CMOS sensor temperature.
You can enable Auto to define a target temperature. For example, here we set the target temperature to –10 °C. The CMOS sensor temperature will quickly drop to the target value, typically within 2–3 minutes.

To disable cooling, select Stop. If you prefer to control the cooling power without setting a target temperature, you can manually set the cooling power as a percentage.

In EZCAP_QT, there is an Image Task Planner for sequence imaging.

Check Use to enable the task.

Set the following parameters:

Bin

ExpTime – exposure time

Repeat – number of frames

CFW – filter wheel position

Gain – gain value for the sequence

Click Folder to set the save path. (It is recommended to avoid special characters in the path and use English letters.)

Click Start to begin the sequence capture, and Force Stop to close the current task.

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: