Pixfra Sirius S635 Thermal Monocular
640x512, 12µm Detector, 35mm Lens
The Pixfra Sirius S635 is a compact yet powerful thermal monocular built for clear, long-range observation. Featuring a 640×512, 12µm thermal sensor with <18mK NETD sensitivity and a 35mm f1.0 lens, it delivers sharp thermal imaging with detection ranges up to 1,800m. A 1920×1080 OLED display, AI-powered image calibration, 64GB built-in storage, and Wi-Fi connectivity add to its versatility, while the quick-release 18650 battery system and IP67-rated housing make it dependable in demanding conditions.
The Pixfra Sirius S635 is a slimline thermal monocular that combines advanced imaging performance with a sleek, ergonomic design. Built around a 640×512, 12µm thermal sensor with an impressive <18mK NETD sensitivity, it delivers exceptional image clarity and picks up even the smallest heat signatures with ease. Paired with a 35mm f1.0 objective lens, the Sirius S635 offers a detection range of up to 1,800 metres, making it a superb choice for wildlife observation, conservation work, and long-range scanning.
A native 2.41x magnification gives you a strong optical starting point, while 1x, 2x, 4x and 8x digital zoom settings provide added flexibility when identifying distant objects. Pixfra’s AI-powered image calibration further enhances image quality by learning from captured images, helping to maintain a crisp, detailed view across changing conditions. The result is a thermal monocular that performs with real confidence in the field.
Viewing is equally impressive thanks to the 0.49-inch 1920×1080 OLED display, which produces a vivid, high-contrast image while remaining comfortable over extended periods of use. With a 50Hz refresh rate, six colour palettes, hotspot tracking, video recording, snapshot capture, and 64GB of built-in storage, the Sirius S635 is well equipped for both live observation and saving footage for later review. Wi-Fi hotspot connectivity also makes it easy to link the device with compatible apps and accessories.
In keeping with Pixfra’s signature styling, the Sirius S635 features a refined, modern finish with subtle design touches including carbon fibre accents, embossed detailing, and an illuminated Pixfra logo power button with five brightness settings that can also be switched off completely when discretion is essential. Its three-button control layout keeps operation simple and intuitive, allowing for comfortable one-handed use, while the metal lens cover provides added protection against dust, knocks, and scratches.
Power comes from a replaceable 18650 battery with up to 6 hours of runtime, and the quick-release battery system makes swaps fast and straightforward when you need longer in the field. Compact at just 421g, and backed by a tough IP67-rated housing with an operating range from -30°C to +55°C, the Pixfra Sirius S635 is built to deliver reliable thermal performance in demanding conditions.
- Thermal sensor 640×512, 12µm, <18mK
- Lens 35mm f1.0
- Focus control Manual
- Close focus distance 3m (9.84ft)
- Field of view H
- Detection range 1,800m (5,905.31ft)
- Digital zoom 1x, 2x, 4x, 8x
- Magnification 2.41x
- Frame rate 50Hz
- Display 1920 × 1080, 0.49 inch, OLED
- Colour palettes 6 (White Hot, Black Hot, Iron Red, Alarm, Amber, Emerald)
- Storage Built-in 64GB
- FFC calibration Auto, Manual, External Correction
- Hot spot trace Yes
- Wi-Fi hotspot Yes
- Video recorder Yes
- Snapshot Yes
- Power source Replaceable 18650 battery
- Battery life Up to 6 hours, depending on temperature
- Power supply 5 VDC / 2A
- Port USB Type-C
- Operating temperature –30°C to +55°C (–22°F to +131°F)
- Level of protection IP67
- Product dimensions 194.3mm × 54mm × 65.4mm (7.65″ × 2.13″ × 2.57″) (L × W × H)
- Net weight 421g (0.93lb)
- Slimline, ergonomic design for comfortable handling and easy one-handed use
- User-friendly three-button control layout for quick access to key functions
- AI-powered image calibration that continually improves image quality based on captured images
- Crystal-clear viewing experience designed to reduce eye fatigue during longer observation sessions
- Six colour palettes to help tailor the image to different environments and viewing preferences
- Hot spot tracking for quickly identifying the warmest point in the scene
- Video recording function for capturing observations as they happen
- Snapshot function for taking still images in the field
- Built-in storage for saving recorded footage and images directly to the device
- Wi-Fi hotspot connectivity for linking the monocular with compatible devices or apps
- Quick-release battery system for fast and easy battery changes during extended use
- Replaceable battery setup for added convenience in the field
- Illuminated logo power button with adjustable brightness settings to indicate device status
- Option to switch the illuminated logo off when complete darkness and discretion are needed
- Metal lens cover for added protection against dust, scratches, and knocks
- Durable weather-resistant construction designed for use in demanding outdoor conditions
- Versatile performance suited to wildlife observation, conservation work, and general thermal spotting
- Pixfra Sirius S635 Thermal Monocular
What is the Pixfra Sirius S635 used for?
The Sirius S635 is a thermal imaging monocular designed for spotting heat signatures in darkness, poor weather, dense cover, or challenging light conditions. It is well suited to wildlife observation, conservation work, and general long-range thermal scanning.
How far can the Sirius S635 detect?
The Sirius S635 has a detection range of up to 1,800 metres, allowing you to pick up heat signatures at impressive distances.
What sensor does the Sirius S635 use?
It uses a 640×512, 12µm thermal sensor with a sensitivity of less than 18mK, helping to produce clear thermal images with strong detail and contrast.
Is the image quality good in poor conditions?
Yes, the Sirius S635 is built to perform well in changing conditions. Its highly sensitive sensor and AI-powered image calibration help maintain a clear, detailed image in a wide range of environments.
What magnification does it have?
The Sirius S635 has a native magnification of 2.41x and also offers digital zoom settings of 1x, 2x, 4x, and 8x for closer viewing.
Does it have a good screen?
Yes, it features a 0.49-inch OLED display with a 1920×1080 resolution, providing a sharp, vivid image that is comfortable to view for longer periods.
Can I record video and take photos with it?
Yes, the Sirius S635 has both video recording and snapshot functions, so you can capture footage and still images directly on the device.
Does it have built-in storage?
Yes, it comes with 64GB of built-in storage for saving recorded videos and images.
Can it connect to my phone or other devices?
Yes, the Sirius S635 includes Wi-Fi hotspot functionality, allowing it to connect with compatible devices and apps.
What colour palettes does it offer?
It offers six colour palettes: White Hot, Black Hot, Iron Red, Alarm, Amber, and Emerald, so you can choose the display style that best suits your preference and conditions.
How long does the battery last?
Battery life is up to 6 hours, depending on temperature and usage.
Can I change the battery easily?
Yes, the Sirius S635 uses a replaceable 18650 battery and features a quick-release battery system for fast and convenient battery swaps.
Is it easy to use one-handed?
Yes, it has been designed with a streamlined three-button control layout that makes operation simple and comfortable, even with one hand.
Is the Sirius S635 durable?
Yes, it has a robust build with an IP67 protection rating, meaning it is designed to handle demanding outdoor conditions and offers strong resistance against dust and water ingress.
Does it come with lens protection?
Yes, it features a metal lens cover to help protect the lens from scratches, dust, and everyday knocks.
Can the illuminated logo be turned off?
Yes, the illuminated Pixfra logo power button can be adjusted across brightness settings or turned off completely when maximum discretion is needed.
Is this monocular suitable for long sessions of use?
Yes, the ergonomic design, clear OLED display, and comfortable handling make it well suited to extended observation sessions.
What makes the Sirius S635 stand out?
The Sirius S635 stands out for its combination of a highly sensitive 640 sensor, long 1,800m detection range, premium OLED display, AI-powered image optimisation, quick-change battery system, and sleek ergonomic design.
- Pixfra 3 year warranty
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