GSTAR-EX4 Deep-Sky Camera
  • DEEP-SKY IMAGER - With its powerful included software, dramatic images of star clusters, galaxies, nebulae and other deep sky objects is possible for printable portraits or simply sitting back and enjoy near real-time live views on your computer monitor.
  • SOLAR SYSTEM IMAGER - Coupled with the cameras super high resolution Sony image sensor, and high-speed USB3 port, you can capture breathtaking images of the planets, lunar surafce or Sun at high-speed USB3 rates.
  • AUTO-GUIDER - Even use this highly versatile camera as an auto-guider with your ST-4 compatible mount via video or ASCOM connection. 
The amazing new GSTAR-EX4 colour camera is your passport to live viewing and imaging the night sky.
The GSTAR-EX4 is USB plug and play ready and utilises the latest high-speed USB3 technology and new generation, low light sensitive Sony Exmor image sensor. With internal thermal cooling fins and extraction fan, the GSTAR-EX4 camera uses Sony's IMX174 high resolution CMOS Sensor with high dynamic range and back-illuminated CMOS image sensor technology. The IMX174 is an "Exmor R" sensor, with significantly enhanced imaging characteristics, including sensitivity and low noise.
High dynamic range was achieved by featuring 12 bit ADC, which reduced quantization noise and suppressed dark random noise. This enables clear image quality in light and dark areas, even when imaging objects with high contrast.
With it's slightly wider field of view over its predecessors, for casual or even serious deep-sky target imaging, the new EX4 stands out. Even for live viewing in full colour, imaging the planets or the Moon, this camera will meet your needs. It is also an ST-4 compliant auto-guider.


Image Sensor: Sony Exmor IMX174 colour  
Size: 1/1.2" (13.4mm diagonal) (3:2 aspect)
Resolution: 1920 x 1200 (2.35 Mega pixels)
Pixels: 5.86μm x 5.86μm
Bit Depth: 8 bit and 12 bit (10 bit / 12 bit A/D converter)
Dust Protection: dust protective window.
Exposure: 0.244 sec ~16 mins
Cooling: Fan vented with heat sink fins (on/off controllable via software)
Connection & power: USB3 (also USB2.0)
Dimensions: 84 (L) x 67mm (W)
Weight: 300 grams
Thread: M42 female
Nosepiece: M42 male to 1.25 inch (threaded for 1.25" filters)
Auto-Guiding: ST4 compliant with ASCOM and WDM drivers
Cables: USB3 and Auto-guide supplied

CD Software:
Includes powerful live viewing, live stacking and capture softwares, including the latest update of GSTAR4 capture V.56 plus ASCOM drivers and auto-guiding software. Compatible with WIN XP, WIN7 WIN8 and WIN10.
Image & video formats: AVI, SER, BMP, JPG, PNG, TIF & FITS


FAN HEATSINK COOLED The GSTAR-EX4 comes with a M42 x0.75 female threaded front housing for direct attachment to M42 male adaptors and providing more inward focus capability. It can also be used in 1.25 inch eyepiece holders with supplied M42 male to 1.25 inch nosepiece adaptor or optional M42 male to 2 inch nosepiece. The rear of the camera features a low brightness red power LED which blinks during operation. A USB3 high-speed port for connecting the camera directly to your computers USB3 or USB2 port with supplied USB cable and ST4 auto-guiding port for connecting the camera directly to your mounts auto-guiding port connector using the supplied 1.5 metre auto-guiding cable. The camera is kept cooled to ambient temperatures via the built-in fan and side vent helping to reduce hot pixels. 

Messier 20
Above: M20 (30 second exposure) and NGC 3372 (10 second exposure) Carina Nebula using a 130mm f/5 Newtonian and GSTAR-EX4  from suburban backyard. Unguided exposures and later stacked with Registax freeware. Auto Dark Frame subtraction feature was used during exposures so no need to apply them later during the stacking process.
M65 captured with GSTAR-EX3 camera
Above: NGC 5139 Omega Centauri using Vixen R130Sf f/5 Newtonian telescope and GSTAR-EX4 camera. Stack of 5 second exposures applying Auto Dark frame subtraction using included TouSky software. 
M65 captured with GSTAR-EX3 camera
Above: Running Man Nebula - 5 second exposures stacked - Vixen R130Sf telescope. 
M65 captured with GSTAR-EX3 camera
Above: IC434 Horse Head Nebula - 15 second exposure time - live stack with Vixen R130Sf telescope. 
M65 captured with GSTAR-EX3 camera
Above: M65 and M66 galaxies in Leo captured in the wide-field image sensor of the GSTAR-EX4 colour deep-sky camera. 



One of the powerful features of the cameras software is the ability to subtract visible hot pixels from long exposures live. Cover the scope, select how many frames to capture then check the "Enable" box.
The software now also features flat field processing of images too.


This is perhaps the key feature of the cameras software whereby deeper views and images can be displayed on screen and captured in real-time using the live stacking option. Just like the GSTAR-EX and EX2 cameras which performed co-add or summing of video frames within the cameras electronics, the images from the GSTAR-EX4 uses external software to perform this task offering a few user options. Option 1) to Co-add a number of user defined images from the camera to display the equivalent of a much longer or deeper exposure or Option 2) to average a user defined number of exposures for displaying a smoother, less noisy result. This is similar to the CSD function of our GSTAR4 capture software although far more flexible and powerful.
If your telescopes mount is fairly well polar aligned and / or tracking pretty accurately, another amazing feature within the "Live Stacking" option is aligning and stacking images in real-time. In other words, images output from the camera can be aligned as well as stacked (with dark frames subtracted for that matter) all at the same time to produce a lovely still image, sequence of still images or video recording at the same time. And, you can stack these later as well for even smoother results using your favourite image stacking software.
Select 8 bit mode or better still, 14 bit mode for greater dynamic range and detail.

M65 captured with GSTAR-EX4 camera

As can be seen from the screen grab of a computer monitor at above, using only a small 130mm f/5 telescope, dramatic full colour views of nebula, galaxies or star cluster is possible and with shorter exposures, wonderful views of the planets or craggy landscapes of the Moon .
Like anything when it comes to modern computer displays, the viewing angle capability of the LED or LCD monitor is important for allowing large group viewing.
The computer monitor view of the Carina Nebula above is a 10 second refreshed exposures utilising live auto-dark frame subtraction and live stacking options of the capture and display software.

Hardware Requirements 

CPU equal to Intel Core2 2.8GHz or better
Memory: 2GB or more
USB Port: USB3.0 High Speed port *
USB Port: USB2.0

**The camera is designed to work optimally with Intel based USB3 port controllers including NEC and many others. However the cameras software may not perform correctly with some older computers that use AS-Media USB3 port controllers in Window 7 but may be ok in WIN8 and later. If this is the case, you can simply use a USB2.0 port.
***Please note: If you do not well understand the basics of using your telescope, its optics and / or have difficulties working with a computer then this product may not be suitable for you.** 


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