TO EXPLORE THE UNKNOWN UNIVERSE
Leo Trio in LRGB with Tidal tail
Integration 10h 50'
Imaging telescope: Takahashi Epsilon 130D
Mount: 10 Micron GM 2000 HPS II Combi
Filter: Astronomik LRGB 36mm · L · G · R
Different from QHY268PH, QHY268PRO is specially designed for scientific using with advanced qualities and functions. QHY268Pro M is a cooled scientific CMOS camera with a SONY IMX571 APS-C format CMOS sensor inside. 26mega pixels, Back-illuminated, native 16BIT ADC. QE is up to 91% and readout noise is as low as 1.1e Even with a 3.76um pixel size, it has a big full-well up to 75ke.
It has extremely low thermal noise 0.0005e/pixel/sec @ -20C, ZERO amplifier-glow performance, It has a maximum frame rate of 6.8FPS@16bit full resolution. QHYCCD IMX571.SONY IMX571/16bit/26Mpixels/BSI/APS-C Format. QHY268PRO has both USB3.0 and 2*10Gbps optical fiber interface. It has a 2GBytes big DDR3 memory buffer. It has the 6pin GPIO port support complex Trig-In and Trig-Out signal. It can connect with QHY GPS-BOX to get the high-precision GPS timestamp onto the image head.
*Since 2022, QHYCCD ONLY provide Mono version for QHY268Pro (QHY268Pro-M).
*Please contact QHYCCD for details and price.
QHY268 Pro M has SONY IMX571 APS-C format CMOS sensor inside. 26mega pixels, Back-illuminated, native 16BIT ADC. QE is up to 91% and readout noise is as low as 1.1e Even with a 3.76um pixel size, it has a big full-well up to 75ke. It has extremely low thermal noise 0.0005e/pixel/sec @ -20C, ZERO amplifier-glow performance, It has a maximum frame rate of 6.8FPS@16bit full resolution.
QHY268PRO-M has only monochrome version. QHYCCD also supplies its liquid-cooling version, which is a customized type and needs to be pre-ordered).
Native 16 bit A/D: The new Sony sensor has native 16-bit A/D on-chip. The output is real 16-bits with 65536 levels. Compared to 12-bit and 14-bit A/D, a 16-bit A/D yields higher sample resolution and the system gain will be less than 1e-/ADU with no sample error noise and very low read noise.
BSI: One benefit of the back-illuminated CMOS structure is improved full well capacity. This is particularly helpful for sensors with small pixels. In a typical front-illuminated sensor, photons from the target entering the photosensitive layer of the sensor must first pass through the metal wiring that is embedded just above the photosensitive layer. The wiring structure reflects some of the photons and reduces the efficiency of the sensor. In the back- illuminated sensor the light is allowed to enter the photosensitive surface from the reverse side. In this case the sensor’s embedded wiring structure is below the photosensitive layer. As a result, more incoming photons strike the photosensitive layer and more electrons are generated and captured in the pixel well. This ratio of photon to electron production is called quantum efficiency. The higher the quantum efficiency the more efficient the sensor is at converting photons to electrons and hence the more sensitive the sensor is to capturing an image of something dim.
TRUE RAW Data: In the DSLR implementation there is a RAW image output, but typically it is not completely RAW. Some evidence of noise reduction and hot pixel removal is still visible on close inspection. This can have a negative effect on the image for astronomy such as the “star eater” effect. However, QHY Cameras offer TRUE RAW IMAGE OUTPUT and produces an image comprised of the original signal only, thereby maintaining the maximum flexibility for post-acquisition astronomical image processing programs and other scientific imaging applications.
Anti-Dew Technology: Based on almost 20-year cooled camera design experience, The QHY cooled camera has implemented the fully dew control solutions. The optic window has built-in dew heater and the chamber is protected from internal humidity condensation. An electric heating board for the chamber window can prevent the formation of dew and the sensor itself is kept dry with our silicon gel tube socket design for control of humidity within the sensor chamber.
Cooling: In addition to dual stage TE cooling, QHYCCD implements proprietary technology in hardware to control the dark current noise.
The product has a built-in 2*10Gbps fiber socket. It can work with the QHYCCD PCIE2.0x8 data grabber card. The fiber interface is for the requirement of the professional obs. It will give the following advantages than the USB3.0 interface. Then what is the benefit of the Fiber Interface?
|COMS Sensor||SONY IMX571 M|
|Pixel Size||3.76um x 3.76um|
|Effective Pixel Area||6280*4210 (includes the optically black area and overscan area)|
|A/D Sample Depth||Native 16-bit (0-65535 greyscale) A/D|
|Full Well Capacity (1×1, 2×2, 3×3)||51ke-
75ke- or above in extended full well mode
|Full Frame Rate||USB3.0 Port:
Full Resolution： 6.8FPS@8BIT 6FPS @16BIT
|Readout Noise||1.1e- High Gain,
3.5e- Low Gain
(5.3e- to 7.4e- in extended full well mode)
|Dark Current||-20C，0.0005e /pixel/sec
|Exposure Time Range||30us-3600sec|
|Unity Gain*||0*（PH Mode）
30（Extended Fullwell Mode）
*With the improvement of the CMOS technology, the 16bit CMOS camera has been released, like QHY600/268/411/461. For these cameras, even in lowest gain it has beyond the requirement of unit gain (less than 1e/ADU due to sufficient samples) So you can directly set gain0 as start. Please note QHY600/268C/411/461 has extend full well mode. In this mode you still need to find out the unit gain position.
|Amp Control||Zero Amplifer Glow|
|Firmware/FPGA remote Upgrade||Fully support via Camera USB port|
|Shutter Type||Electronic Shutter|
|Computer Interface||USB3.0 and 2*10Gbps Fiber interface|
|Built-in Image Buffer||2Gbyte DDR3 Memory|
|Cooling System||Two-stage TEC cooler
Air Cooling Version
Typical -30C below ambient in short exposure time (exposure time < 10sec)
Typical -35C below ambient in long exposure time (exposure time > 30sec)
（Test temperature +20°）
Water Cooling Version
Typical -45C below ambient in long exposure time (exposure time > 30sec)
|Optic Window Type||AR+AR High Quality Multi-Layer Anti-Reflection Coating|
|Telescope Interface||Support M54 and M48 (with standard adapters )|
|Back Focal Length||QHY268M: 14.5mm*
*If used with the QHY filter wheel, the actual “BFL Comsumed” is 12.5mm. Note 14.5mm rear intercept does not include adapter thread, which must be used with adapters if you need a M54 thread.
Multiple Readout Modes is a new function for newer QHY Cameras. Different readout modes have different driver timing, etc., and result in different performance. The QHY268 currently has four readout modes, and more modes will be added in the future. These readout modes are currently supported in the QHY ASCOM Camera Driver, SharpCAP software and the N.I.N.A software.
Readout Mode #0 (Photographic Mode). In this mode there is a drop in the noise between Gain 25 and Gain 26. We recommend setting the Gain to 26 to begin. At this setting the full well is 27ke- and readout noise is 2.7e-. For every long exposures you can lower the gain from this point to increase the full well capacity.
Readout Mode #1 (High Gain Mode). Please note there is a HGC/LGC switch point at gain55 to gain56. Gain0-55 uses LGC and Gain55-100 uses HGC.
Readout Mode #2 (Extended Fullwell Mode).
Now QHY268 adds #3 mode Extend Fullwell 2CMSIT (yellow curve). The advantage of this mode is that it has the same full well value and system gain as the #2 mode Extend Fullwell, but the read noise is reduced by about 1.3 times.
This function needs to be used with 2020.6.26 or newer SDK. If your software cannot display this mode, please download the QHYAllInOne installation package to update the SDK in the software.
Monochrom’s Spectrum Response Curve. The curve is based on SONY’s datasheet. In the datasheet, it is the normalized curve QHYCCD test it by comparing with an known QE CCD sensor. And get this curve. This curve is only a reference. QHYCCD does not guarantee this curve is correct.
The camera requires an input voltage between 11V and 13.8V. If the input voltage is too low the camera will stop functioning or it may reboot when the TEC power percent is high, causing a drain on the power. Therefore, please make sure the input voltage arrived to the camera is adequate. 12V is the best but please note that a 12V cable that is very long or a cable with small conductor wire may exhibit enough resistance to cause a voltage drop between the power supply and the camera. The formular is: V(drop) = I * R (cable). It is advised that a very long 12V power cable not be used. It is better to place the 12V AC adapter closer to the camera.
First connect the 12V power supply, then connect the camera to your computer via the USB3.0 cable. Make sure the camera is plugged in before connecting the camera to the computer, otherwise the camera will not be recognized. When you connect the camera for the first time, the system discovers the new device and looks for drivers for it. You can skip the online search step by clicking “Skip obtaining the driver software from Windows Update” and the computer will automatically find the driver locally and install it. If we take the 5IIISeries driver as an example (shown below), after the driver software is successfully installed, you will see QHY5IIISeries_IO in the device manager.
Please note that the input voltage cannot be lower than 11.5v, otherwise the device will be unable to work normally.
All-in-one Pack (Windows) is for all QHYCCD USB3.0 devices, including all Cooling CMOS cameras, QHY5III and QHY 5II series, QHYCFW3. We recommend you choose “Stable Version” as usual.
In this pack there are:
1. System driver. It must be installed to make devices work.
2. EZCAP_QT: it’s developed by QHYCCD which could be used in QHY devices tests, simple capture tasks, and above all, the management of updates. So even if you won’t use EZCAP_QT as your main capture software, we suggest you install it to get the latest information of QHY drivers/SDK updates.
3. Ascom driver: Ascom Platform is supported by most astronomy devices which connect to Windows.
4. SDK: SDK is the file of “.dll” format. With this the device can be identified in other capture software.
5. SkyX Plugin: special support for SkyX.
6. QHYCCD BroadCast WDM Driver: It is a broadcast driver that supports QHYCCD cameras with video broadcast function, which can meet the needs of customers to send video images to other target software.
How to install it?
Take SharpCap (x64) for example:
Before the installation, make sure you’ve already installed SharpCap (X64) on your PC;
Then click ”Third Party Software Support” – “SharpCap 64”, the pack will detect the location of SharpCap files and install automatically; if not, please manually select root directory of SharpCap where you installed it, like: C:\Program Files\SharpCap 3.2 (64 bit)
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 a planetary/guiding camera, 12V power is not needed.
Note: We recommend 64-bit Software when you’re using cameras with a large sensor, such as QHY600. A full resolution image from the QHY600 is 120MBytes. It takes a significant amount of processing power and memory to capture, buffer, display and process. We therefore suggest using 64-bit software with the QHY600, for example, SharpCAP x64 , N.I.N.A x64. etc. Although the camera has 4GB of internal memory, 32-bit software will run within this memory area and the remaining memory may be not sufficient for normal operation.
EZCAP_QT is software developed by QHYCCD. This software has basic capture functions for QHYCCD deep sky cameras.
Run EZCAP_QT. Click “Connect” in Menu -> Camera. If the camera is successfully connected, the title line of EZCAP_QT will display the camera firmware version and the camera ID as shown below.
Click “Temperature Control” in “Camera Settings” to set the temperature of the CMOS sensor. You can turn on “Auto” to set the target temperature. For example, here we set the target temperature to -10C. The temperature of the CMOS sensor will drop quickly to this temperature (approximately 2-3 minutes). If you want to turn off cooling, you can choose Stop. If you just want to set the TEC power but not the temperature. You can select “Manual” and then set the percentage of the TEC power.
You can use the “preview tab” to preview and use the focus tool to focus. Then use the “capture tab” to capture the image.
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.
With ASCOM drivers, you can use the device with many software packages that support the ASCOM standard. We will use Maxim DL below as an example, but a similar procedure is used for The SkyX and other software packages supporting ASCOM.
First make sure you have not only loaded the ASCOM drivers but that you have also downloaded and installed the ASCOM platform from ASCOM. After both the drivers and platform are installed, start MAXIMDL. Follow the instructions shown below to finish the setup. Then Click Connect in and enter the software.
QHYCCD BroadCast WDM Camera is a broadcast driver that supports QHYCCD cameras with video broadcast function, which can meet the needs of customers to send video images to other target software. For example, use sharpcap to connect a WDM-enabled camera, and the sharpcap display video image can be sent to other WDM-supported software for display, which is suitable for video online broadcast applications.
The installation process is over, right-click the computer to find the device manager, and check that the image device name is QHYCCD BroadCast WDM Camera, which means the installation is successful.
HANDYAVI test effect chart:
UFOCAPTURE test renderings:
|mode 0||mode 1||mode 2||mode 3||mode 4||mode5||mode6|
To avoid the problem of unreliable USB connection or port damage caused by leakage of computer or 220V to 12V adapter
Some computers or 220V to 12V adapters have leakage currents. If they are not well grounded, a high voltage is formed between the ground (metal case) of the USB interface and the ground (metal case) of the power supply line. If the USB and power supply wires are in good contact with the camera, the device can operate normally due to the formation of a common ground at the camera.
However, the common ground formed at the camera is very dangerous. On the one hand, it is easy to cause the USB connection to be unreliable, and the USB connection is often lost during use, and on the other hand, there is a risk of potentially damaging the port. Therefore, make sure the computer and adapter are well grounded before putting the device into service.
You can use the multimeter’s AC voltage file to detect if there is any leakage between the computer and the adapter. The method is not to connect the camera first, one meter is connected to the metal case of the USB plug, and the other meter is connected to the negative pole of the DC output plug of the power adapter (generally inside and outside negative). If the voltage between the two is small, there is no leakage or a good ground has been achieved through the ground of the power plug. If there is a voltage of several V to several tens of V, there is leakage and there is no good grounding. Need to check if the 220V power plug can provide a good ground.
If there is no way to avoid it, you need to use a separate wire to connect the ground of the computer (usually connected to the metal case) and the negative pole of the 220V to 12V adapter to achieve common ground.
The CMOS sensor is located in the CMOS chamber. There is a hole in the side of the camera near the front plate that is normally plugged by a screw with an o-ring. If there is moisture in the CMOS chamber that causes the sensor glass to fog, you can connect the silica gel tube to this hole for drying the chamber.
Place an effective silica gel desiccant in the silica tube make sure there is some cotton inside to prevent the silica gel from entering the CMOS chamber.
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.
If the ambient humidity is very high, the optical window of the CMOS chamber may have condensation problems. The QHY600 has a built-in heating plate to heat it to prevent fogging. In most cases, it is very effective. However, If fogging still persists, try the following:
1. Avoid directing the camera towards the ground. The density of cold air is greater than the density 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. Increase the temperature of the CMOS sensor. You can increase the temperature of the CMOS sensor slightly to prevent fogging of the glass.
3. Check if the heating plate is working. If the heating plate is not working, the glass will be very easy to fog. Normally, the temperature of the heating plate can reach 65-70 °C in the environment of 25 °C. If it does not reach this heat, it may be because the heating plate is damaged, you can contact us to replace the heating plate.
You should 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.
Note: Now only QHY600, QHY268, QHY410, QHY411, QHY461, QHY533 cameras have UVLO function.
What is UVLO?
UVLO（Under Voltage Locking), is primarily intended to protect the electronic device from damage caused by abnormally low voltages.
Our daily life experience tells us that the actual operational voltage of an electrical device must not significantly exceed the rated voltage, otherwise it will be damaged. For such precision equipment as cameras, long-term work at too low input voltage can also be detrimental to the working life of the camera, and may even make some devices, such as power manager, burn up due to long-term overload. In the all-in-one driver and SDK after 2021.10.23 stable version, the camera will give a warning when the input voltage of the camera is below 11V.
UVLO warning execution
After a warning is given, the camera firmware will automatically turn off the cooler and will turn on the camera’s TEC protection mode. After the camera is reconnected, it will always work in TEC protection mode (maximum power cooler power will be limited to 70%). Since many times the voltage shortage is caused by the high resistance of the power supply cable itself, resulting in a large voltage drop at high currents, the voltage will usually rise after the power is limited. But limiting the power will affect the cooling temperature difference. Therefore, it is recommended that users first check the power supply cable to solve the problem of excessive resistance of the power supply cable.
If the user has solved the problem of insufficient supply voltage, the TEC protection mode can be removed through the menu of EZCAP_QT.
How to improve the power supply?
How to clear the TEC protection status triggered by UVLO?
Once a UVLO event occurs, the camera will automatically memorize it and will work in a protected mode at a maximum of 70% power after reconnection. This memory can be erased as follows:
After you find the system error, you need to turn off the device and check the power supply. After inspecting the problem, open the ezcap software and select “Camera Settings” – “Preferences” – “Reset Flash Code” to reset the error status.
Why does the warning appear even though the power supply voltage is 12 V?
Added functions related to BURST mode in SDK. Currently, cameras that support Burst function include QHY600, QHY411, QHY461, QHY268, QHY6060, QHY4040, QHY4040PRO, QHY2020, QHY42PRO, QHY183A
This mode is a sub-mode of continuous mode. This function can only be used in continuous mode. When this function is enabled, the camera will stop outputting image data, and the software frame rate will be reduced to 0. At this time, send relevant commands to the camera, and the camera will Output the image data with the specified frame number according to the settings, for example, set Start End to 1 6, the camera will output the image data with the frame number 2 3 4 5 when receiving the command.
1. When using Burst mode in fiber mode, the first Burst shot will be one less. For example, if the start end is set to 1 6, the output of 2 3 4 5 is normal, but in fact, only 3 4 will be output during the first burst shot. 5, 2 will not be received, the second and subsequent shots can normally obtain Burst images 2 3 4 5. This problem will be fixed later.
2. QHY2020, QHY4040 found that the frame number that came out when the exposure time was short is [start+1,end-1] but the one that came out under long exposure was [start+2,end]
3. When the camera is just connected, if the set end value is relatively large, the camera will directly output the picture after entering the burst mode. Therefore, it is necessary to set the camera to enter the IDLE state and then set the start end and related burst operations.
The following is the usage of Burst mode related functions: