GPM462M User Manual
Version 1.0, Nov 2023
Copyright © ToupTek Photonics
Download the latest version from touptek.com.
1 Description and Features
The GPM462M camera excels at capturing infrared light with high Quantum Efficiency (QE) at 500nm. It offers a large full well capacity, high dynamic range, high sensitivity, and low readout noise, making it suitable for planetary, solar, and lunar photography.
Key Features:
- IMX 462 Mono CMOS Sensor
- Resolution: 1920 x 1080
- Pixel Size: 2.9 µm
- Optical Format: 1/2.8-inch
- ADC: 12-bit
- Built-in Frame Buffer
- G Sensitivity: 10819mV with 1/30s
- Low Noise: 0.76 to 2.61e-
- Frame Rate: 18 FPS (8-bit readout)
- SNR Max: 41 dB
- Dynamic Range: 73.7 dB
2 GPM462M Specifications and Performance
2.1 Camera Specifications
| Sensor | Sony IMX462 back illuminated sensor |
| Diagonal | 6.39 mm |
| Image Resolution | 2.1 mega pixels (1920*1080) |
| Pixel Size | 2.9µm × 2.9µm |
| Image Area | 5.57mm × 3.13mm |
| Max FPS at Resolution | 12bit: 8.9 FPS @ 1920*1080; 8bit: 17.8 FPS @ 1920*1080 |
| Shutter Type | Rolling shutter |
| Exposure Time | 0.1ms – 1000s |
| Gain | 1x – 500x |
| SNR | 41 dB |
| Dynamic Range | 73.7 dB |
| Read Noise | 2.61 – 0.76 e- |
| QE Peak | >89% |
| Full Well | 12.7ke- |
| ADC | 12bit |
| Frame Buffer | Built-in |
| Connection Port | USB2.0 Type C |
| Camera Adaptor | Standard 1.25" for telescope connection, and standard C adapter for industrial lens |
| Protect Windows | IR-cut filter/AR-window |
| Spectral Range | 380-1100nm (with AR protect window) |
| Capture/Control SDK | Windows/Linux/macOS/Android Multiple Platform SDK(Native C/C++, C#/VB.NET, Python, Java, DirectShow, Twain, etc.); |
| Recording System | Still picture and movie |
| Camera Dimensions | Diameter 37mm * height 72.4mm |
| Camera Weight | 70 gram |
| Back Focus Distance | Back Focus Distance is 8.5mm, 17.5mm with C adapter, 12.5 with CS adapter |
| Cooling: | Passive cooling |
| Supported OS | Microsoft® Windows® XP / Vista / 7 / 8 /10 (32 & 64 bit) OSx(Mac OS X) Linux |
2.2 Sony IMX462 Sensitivity
The sensor's G Sensitivity is 10819mV at 1/30s. Spectral sensitivity is illustrated in Figure 1, measured using a purple LED light source (2850 K) and an IR-cut filter (CM700, 1.0 mm) placed between the light source and the sensor.
Figure 1: IMX462 Spectral Sensitivity Characteristic A line graph titled "IMX462 Spectral Sensitivity Characteristic". The X-axis represents Wavelength [nm] from 400 to 1000. The Y-axis represents Relative response [a.u.] from 0.0 to 1.0. The line shows a peak response around 650-700nm, gradually decreasing towards shorter and longer wavelengths.
2.3 12bit ADC and ROI
The GPM462M features a 12-bit ADC and supports a 12-bit output mode for hardware binning and reduced resolution, enhancing frame rates. Hardware Region of Interest (ROI) is also supported, with smaller ROIs yielding higher frame rates.
| Resolution | Bit & Interface | 12bit ADC USB2.0 | 8bit ADC USB 2.0 |
| 1920*1080 | FPS | 8.9 | 17.8 |
2.4 Frame Buffer
A built-in frame buffer stabilizes data transmission and reduces amp-glow by buffering image data before sending it to the receiver, ensuring maximum frame rates even with multiple cameras.
2.5 Binning
The camera supports digital binning from 1×1 to 8×8 using stacking or averaging methods.
2.6 Conversion Gain Switch
Supports HCG (High Conversion Gain) and LCG (Low Conversion Gain) modes.
2.7 Power and Cooling System for Precise Temperature Regulation
The camera operates via a USB 2.0 interface. Upon connection to the host system, the device is ready for operation.
2.8 Camera Performance Analysis
Performance is evaluated using e-/ADU, Read Noise, Full Well, and Dynamic Range.
e-/ADU: Represents the conversion factor from electrons to digital counts (Analog-Digital Units).
Read Noise: Crucial for image quality, lower read noise means better SNR. It originates from camera electronics during readout.
Full Well: The maximum charge a pixel can hold, indicating light-gathering capacity. Higher full well capacity generally leads to wider dynamic range.
Dynamic Range: The ratio of maximum output signal to noise floor, indicating the camera's ability to capture detail in both bright and dark areas.
Gain Value is expressed in xxx% mode. Formulas are provided for Rel Gain (dB) and Gain Value: Rel Gain(dB) = 20 * log10[xxx(Gain Value)/100]; xxx(Gain Value) = 100 × 10(Rel Gain(dB)/20).
Figure 2: e/ADU, Read Noise, Full Well and Dynamic Range for GPM462M (LCG Mode) Four line graphs showing camera performance in LCG mode against Gain Value. The X-axis represents Gain Value (from 100 to 4999). The four graphs show trends for e/ADU, Read Noise, Full Well, and Dynamic Range, generally decreasing as Gain Value increases.
| Gain Value | 100 | 177 | 316 | 562 | 1000 | 1778 | 3162 | 4999 |
| Rel Gain (dB) | 0.00 | 4.87 | 9.95 | 14.82 | 19.83 | 24.91 | 29.82 | 33.93 |
| e-/ADU | 3.09 | 1.77 | 0.98 | 0.56 | 0.32 | 0.18 | 0.10 | 0.06 |
| Read Noise (e-) | 2.61 | 2.21 | 1.98 | 1.85 | 1.75 | 1.64 | 1.59 | 1.59 |
| Full Well (ke-) | 12.7 | 7.2 | 4.0 | 2.3 | 1.3 | 0.7 | 0.4 | 0.3 |
| Dynamic Range (stop) | 12 | 11.68 | 10.99 | 10.28 | 9.53 | 8.78 | 8.01 | 7.33 |
Figure 3: e/ADU, Read Noise, Full Well and Dynamic Range for GPM462M (HCG Mode) Four line graphs showing camera performance in HCG mode against Gain Value. The X-axis represents Gain Value (from 100 to 4999). The four graphs show trends for e/ADU, Read Noise, Full Well, and Dynamic Range, generally decreasing as Gain Value increases.
| Gain Value | 100 | 177 | 316 | 562 | 1000 | 1778 | 3162 | 4999 |
| Rel Gain (dB) | 0 | 4.85 | 9.9 | 14.75 | 19.72 | 24.77 | 29.65 | 33.62 |
| e-/ADU | 1.18 | 0.67 | 0.38 | 0.22 | 0.12 | 0.07 | 0.04 | 0.02 |
| Read Noise (e-) | 1.1 | 0.96 | 0.88 | 0.84 | 0.80 | 0.77 | 0.75 | 0.76 |
| Full Well (ke-) | 4.8 | 2.8 | 1.5 | 0.9 | 0.5 | 0.3 | 0.2 | 0.1 |
| Dynamic Range (stop) | 12 | 11.5 | 10.78 | 10.04 | 9.29 | 8.5 | 7.72 | 7.05 |
3 Product Package and Connections
3.1 Packing List
The standard camera packing list includes:
- Carton (not shown)
- Gift box
- GPM series camera with Type-C-Mount
- High-speed USB3.0 A male to C male connectors cable (2.0m)
- 1.25-inch nosepiece
- ST4 guide cable (2.0m)
- CS-mount ring
Figure 4: Packing Information of GPM462M An image displaying the components included in the GPM462M package: a blue camera body, a gift box, a USB cable with Type-C connector, a 1.25-inch nosepiece, an ST4 guide cable, and a CS-mount ring.
3.2 Camera Dimension and Its Mount
The GPM series body is constructed from tough alloy for durability. It features a high-quality IR-CUT or AR filter to protect the sensor and manage reflection light. The design is rugged and robust.
| Item | Specification |
| 1 | Directly with 1.25" telescope; |
| 2 | GPM + 1.25" extender with 1.25" telescope |
| 3 | Standard C adapter connects to industrial C-mount adapter lens. |
Figure 5: Dimension and Mount of GPM462M and 1.25" extender A technical drawing showing the dimensions of the GPM462M camera and its mounting options. It indicates the camera body diameter (31.7mm and 36mm), length (48mm and 66mm), optical distance (12.5±0.2mm), and the 1"-32 UNF-2B thread for mounting. It also shows the 1.25" extender.
3.3 Camera Outline and Interface
The camera features an ST4 auto guider port and a USB2.0 Type C interface.
Figure 6: Camera Outline and Interface. A diagram showing the camera's outline and highlighting its interfaces: a USB Type-C port and an ST4 auto guider port.
| Item | Specification |
| 1 | A built-in ST4 auto guider port for the easy connection of the auto guider. |
| 2 | USB2.0 interface, Type C |
4 GPM462M and Its Software
4.1 Application Installation
Software, including the latest ToupSky, can be downloaded from touptek-astro.cn. The GPM camera is also compatible with ASCOM and DirectShow SDKs.
ToupSky is ToupTek's Windows application for astronomy cameras, offering control, capture, processing, browsing, and analysis.
Windows Requirements:
- x86: Windows XP SP3 or later, CPU with SSE2 instruction set
- x64: Windows 7 or later
ToupSky Features:
- Full camera control
- Trigger and video modes (RAW or RGB)
- Automatic capture and quick recording
- Multi-language support
- Hardware ROI and digital binning
- Extensive image processing (stitching, live stacking, flat/dark field correction)
Supported Cameras:
- All ToupTek astronomy cameras
4.1.1 User-friendly UI Design
ToupSky features well-arranged menus and toolbars, a three-sidebar design (Camera, Folders, Undo/Redo), convenient operating methods (double-click/right-click menus), and a detailed help manual.
Figure 7: ToupSky and Its Video Window A screenshot of the ToupSky software's video window. It shows a live preview of an astronomical image (the Moon) and a control panel on the left with options like Capture & Resolution, Color Balance, Exposure & Gain, etc.
Figure 8: ToupSky and Its Browse Window A screenshot of the ToupSky software's browse window, displaying thumbnails of captured astronomical images (Mars, Moon, Jupiter, etc.) and file path information.
4.1.2 Professional Camera Control Panel
| Control Panel Section | Description |
| Capture & Resolution | Set live and snap resolution; capture images or record video. |
| Exposure & Gain | Auto exposure (target preset) and manual exposure (time input); up to 5x gain. |
| Color Balance | Advanced single-click white balance; manual adjustment of temperature and tint. |
| Color Adjustment | Hue, saturation, brightness, contrast, gamma initialization. |
| Frame Rate | Adjustable frame rate for different computer configurations. |
| Flip | Select horizontal or vertical correction for sample direction. |
| Sampling | Bin mode for low noise video; Skip mode for sharper video. Supports histogram extension, negative/positive switching, gray calibration, and clarity focus. |
| Bit Depth | Switch between 8-bit (standard Windows format) and 12-bit (higher quality, moderate FPS). |
| ROI | Region of Interest. Set ROI on the video window using handles. Apply to set video to ROI size; Defaults to original size. |
| Dark Field Correction | Capture dark field image first. Enable/disable button becomes active after capture. |
| Cooling | Set TE-Cooling target temperature and fan On/Off. |
| Parameters | Load, save, overwrite, import, export custom camera control panel parameters (calibration, exposure, color settings). |
4.1.3 Practical Functions with Good Results
Video functions
Supports video broadcast, time lapse, video record, video stream grid, image stitching, and adding scale bars/dates.
Image Processing and Enhancement
Offers image adjustment via denoise, sharpen, color toning, filtering, morphology algorithms, range, binary, pseudo-color, surface plots, and line profiles.
Image Stacking
Utilizes advanced image matching for stacking, reducing noise by aligning shifting, rotation, and scaling.
Figure 9: Image Stacking A visual representation of image stacking, showing multiple input images (nth image, (n-1)th image, etc.) being processed to produce a final stacked image with reduced noise.
4.1.4 Powerful Compatibility
- Video Interface: Twain, DirectShow, SDK Package (Native C++, C#/VB.NET)
- Operating System: Compatible with Windows (XP SP3+, Vista, 7, 8, 10 - 32/64-bit), macOS, Linux
- Language Support: Multiple languages including English, Chinese, Russian, German, French, Polish, Turkish.
4.1.5 Hardware Requirement
PC Requirements:
- CPU: Intel Core 2 2.8GHz or higher
- Memory: 2GB or more
- USB port: USB3.0/USB2.0
- Display: 17" or larger
- CD-ROM: Required
4.2 GPM462M and Dshow
ToupTekDshowAstroSetup provides a Dshow standard interface driver for ToupTek USB astronomy cameras.
Supported OS:
- Windows: x86 (XP SP3+ with SSE2), x64 (Win7+)
Supported Cameras:
- All ToupTek astronomy cameras
4.3 GPM462M and the 3rd Party Software
4.3.1 Support Software
| No. | Software | Version | WDM | ASCOM | Native |
| 1 | PHD Guiding | 2.3.0(2014) | √ | √ | √ |
| 2 | Nebulosity | 3.2.2(2014) | √ | X | / |
| 3 | MaxIm DL | 5.23(2013) | √ | X | / |
| 4 | SharpCap | 2.1(2014) | √ | X | / |
| 5 | MetaGuide | 5.2.0(2014) | √ | / | / |
| 6 | FireCapture | 2.4.05(2014) | √ | / | / |
| 7 | Astroart | 5.0(2014) | √ | X | / |
4.3.2 ASCOM Platform
All AstroCam telescope camera drivers require the ASCOM platform, available for free download from ascom-standards.org.
4.3.3 PHD Guiding
A popular free guiding software. Download from openphdguiding.org. ToupTek cameras support Native/ASCOM/WDM drivers.
4.3.4 Nebulosity
A cooled camera control and image processing software, supported via ASCOM.
4.3.5 MetaGuide
Autoguiding software for atmospheric agitation. Supports GCMOS01200KPB. More info at astrogeeks.com.
4.3.6 MAXIMDL
A comprehensive CCD control and image processing software popular in the US.
4.3.7 AstroArt
A comprehensive CCD control and image processing software popular in Europe.
4.3.8 FireCapture
Free planetary capture software, supporting AstroCam series cameras.
4.3.9 SharpCAP
Free planetary capture software supporting WDM cameras, including AstroCam series.
4.3.10 Registax
Popular free software for planetary stacking and processing.
4.3.11 AstroStack
Planetary stacking and processing software.
4.3.12 DeepSky Stacker
Free software for deep sky image stacking and processing.
5 Service
For software upgrades, visit the official website ToupTek.com.
Contact local dealers for inquiries or email karas@ToupTek.com for technical support.
