GUIDE ORION O435CS CLIP-ON 400 X 300 PX THERMAL IMAGING CAMERA

The Guide Orion O435CS is a compact thermal attachment designed for installation in front of a conventional daytime riflescope using a compatible adapter. Its 400 × 300 VOx detector, ≤15 mK thermal sensitivity and fast 35 mm F0.9 lens help distinguish subtle temperature differences in darkness and challenging weather. Weighing only 285 g, it adds relatively little weight while allowing the user to retain the familiar reticle, eye relief and handling of the existing daytime optic.

Suitable for use

• Observation and lawful hunting in darkness

• Woodland, field edges and mixed terrain

• Fog, light rain and reduced-visibility conditions

• Adding thermal capability to an existing daytime riflescope

• Users looking for a lightweight thermal attachment

• Multiple optic or firearm configurations

• Wet, dusty and cold outdoor conditions

• Situations requiring rapid startup and uncomplicated controls

Why choose the Guide Orion O435CS?

• 400 × 300 VOx detector with a 12 μm pixel pitch

• High thermal sensitivity of ≤15 mK

• Fast 35 mm F0.9 germanium objective

• ApexVision S1 imaging architecture

• Hyper-Light 2.0 image-processing algorithm

• Smooth 50 Hz refresh rate

• 1024 × 768 AMOLED display

• Manufacturer-specified detection range of up to 1800 m

• Supports daytime-scope magnification up to 10×

• Approximately three-second startup

• Five storable correction profiles

• Seven thermal colour palettes

• Compact body weighing only 285 g

• Replaceable 18500 battery

• USB-C external-power connection

• IP67 environmental protection

• Recoil resistance of up to 6000 J

Technical specifications

• Product code: GUIDEO435CS

• Brand: Guide

• Model: Orion O435CS

• Product type: Front-mounted thermal clip-on

• Imaging architecture: ApexVision S1

• Detector type: Uncooled VOx

• Spectral range: 8–14 μm

• Sensor resolution: 400 × 300 px

• Pixel pitch: 12 μm

• Thermal sensitivity: ≤15 mK

• Refresh rate: 50 Hz

• Objective lens: 35 mm

• Lens aperture: F0.9

• Focusing: Manual

• Native magnification: 1×

• Angular field of view: 7.9° × 5.9°

• Field of view at 100 m: 13 × 10 m

• Manufacturer-specified detection range: Up to 1800 m

• Daytime-scope magnification: Up to 10×

• Display type: AMOLED

• Display size: 0.39"

• Display resolution: 1024 × 768 px

• Colour palettes: White Hot, Black Hot, Red Hot, Green Hot, Iron Red, Blue Hot and Sepia

• Startup time: Approximately 3 seconds

• Storable correction profiles: 5

• Eye relief: 20 mm

• Power supply: 1 × replaceable 18500 rechargeable battery

• Operating time: Up to 6.5 hours per battery

• External power: USB-C

• Device-side mounting thread: M33.5 × 0.75

• Recoil resistance: Up to 6000 J

• Protection rating: IP67

• Operating temperature: –20 to +50 °C

• Dimensions: 99 × 73 × 68 mm

• Weight: 285 g

Supplied with

• Guide Orion O435CS thermal clip-on

• 2 × rechargeable 18500 batteries

• Battery charger

• USB-A to USB-C cable

• Carrying case

• Accessory pouch

• Optics-cleaning cloth

• Quick-start guide

• Warranty card

The front adapter required for connection to a daytime riflescope must be selected separately and is not part of the standard package.

Frequently asked questions

Is a riflescope adapter included?

No. The standard O435CS package does not include a front adapter. The adapter must be selected according to the outside diameter of the daytime scope’s objective housing and the adapter system being used.

How should the adapter size be selected?

The adapter must match the outside diameter of the scope’s objective housing, not its nominal objective-lens diameter. A riflescope with a 50 mm objective, for example, will normally have a considerably larger external housing. Measure the housing with callipers or confirm compatibility with the retailer before ordering. The clip-on’s device-side thread is M33.5 × 0.75.

Does the 1800 m figure represent identification or shooting range?

No. It is the manufacturer-specified detection distance at which a human-sized or large-animal heat source may be noticed under suitable conditions. Reliable recognition and identification distances are shorter and depend on weather, target size, background, daytime-scope magnification and the observer’s experience.

What daytime-scope magnification can be used?

The manufacturer lists compatibility with daytime-scope magnification up to 10×. Increasing the magnification also enlarges the pixels of the thermal display, so the image becomes progressively more pixelated and the visible field narrows. Moderate magnification will usually provide the most balanced image.

What are the five correction profiles used for?

They allow alignment information to be stored for different optics or mounting configurations. Each firearm, scope and adapter combination should be treated as a separate setup and its point of impact must be checked safely at an authorized shooting range after installation.

Can the O435CS be used in rain?

Its IP67 rating provides protection against dust and temporary immersion in water. This makes it suitable for normal outdoor conditions, but it should not be treated as diving equipment. Ensure that all connector covers are properly closed before use.

How long does the battery last?

Thermshop specifies operating time of up to 6.5 hours from one 18500 battery. Actual runtime depends on temperature, display brightness, usage and battery condition. Two replaceable batteries are supplied, allowing a discharged battery to be exchanged in the field.

When is the Guide Orion O435CS the right choice?

The O435CS is well suited to users who want to add thermal capability to an existing daytime riflescope while retaining its familiar reticle, eye relief and controls. Its 35 mm lens provides a useful balance between field of view and detection distance, while the 285 g body keeps the complete setup comparatively light.

Thermal sensitivity of ≤15 mK is particularly valuable when the temperature difference between an animal and its surroundings is small, such as during damp, foggy or thermally uniform weather. A model with a 640 × 512 detector may be preferable when maximum detail, higher daytime-scope magnification or improved long-distance recognition is the main priority, although it will normally cost more and may be larger.

A dedicated thermal sight may be more appropriate when retaining a daytime optic is unnecessary. A handheld thermal imager remains the more comfortable choice for prolonged scanning because the surroundings can be observed without moving the firearm.

Expert recommendation

The performance of a front attachment depends heavily on accurate adapter fit. Measure the outside diameter of the daytime scope’s objective housing, confirm compatibility with the O435CS’s M33.5 × 0.75 interface and make sure the attachment remains aligned with the optical axis. An overtightened or crooked adapter can alter alignment and may damage the scope housing.

After initial installation, verify the point of impact safely at an authorized shooting range and save a separate correction profile for that configuration. Repeat the check after changing the adapter or following a substantial impact. The 6000 J recoil rating describes the device’s resistance, but it does not automatically guarantee compatibility with every firearm, mount and adapter combination.

In cold weather, keep the spare battery in a warm inner pocket whenever practical. Remove loose dust with air or a soft brush before wiping the objective with an optics cloth. Always use the thermal device in accordance with applicable hunting, firearm and wildlife regulations.

Lightweight thermal capability for an existing daytime optic

The Guide Orion O435CS combines a 400 × 300 detector, ≤15 mK thermal sensitivity, a fast 35 mm F0.9 lens and a compact 285 g body. Rapid startup, five correction profiles, replaceable batteries and IP67 protection make it a practical front attachment for users who want to retain their familiar daytime optic in darkness and reduced-visibility conditions.