The Planewave CDK20 features a focal ratio of f/7.77 and a focal length of 3951 mm. This design eliminates common optical aberrations, providing images free of coma, off-axis astigmatism, and field curvature. As a result, it delivers pinpoint star images across a 52mm image circle. 

The telescope is equipped with rock-solid fused silica mirrors that exhibit low thermal expansion, ensuring consistent performance. Its carbon fiber optical tube assembly offers exceptional rigidity and promotes rapid cooling. Additionally, the fixed primary mirror design simplifies secondary mirror collimation, making adjustments straightforward and precise.

The Corrected Dall-Kirkham (CDK) 20″ telescope, designed and manufactured with a focus on performance and ease of use, represents a remarkable advancement in telescope technology. The CDK20 eliminates off-axis coma and off-axis astigmatism, delivering images with stunning clarity from corner to corner, free from field curvature.

Astrophotographers will appreciate the perfectly flat field, ensuring their photos remain sharp and clear across the entire image. The telescope's design includes the simplicity of single-mirror collimation, advanced baffles for stray light control, and structural integrity achieved through finite element analysis (FEA). Backed by decades of telescope design experience, the CDK20 stands out as an exceptional diffraction-limited telescope.

Users of the CDK20 can enjoy pinpoint stars across a 45 x 45 arcminute field of view when using large 16803 size camera sensors. By fading into the background and delivering consistent performance, the CDK20 enhances the astrophotography experience, making it more enjoyable and rewarding.

• Focal Ratio: f/7.77
• Focal Length: 3951 mm
• Optical Quality: No coma, no off-axis astigmatism, and no field curvature
• Image Quality: Pinpoint stars across a 52mm image circle
• Mirror Material: Rock solid fused silica mirrors with low thermal expansion
• Optical Tube: Carbon fiber optical tube assembly for rigidity and fast cooling
• Collimation: Simple secondary mirror collimation thanks to the fixed primary mirror

The CDK20 telescope features an advanced carbon fiber truss design, engineered to minimize thermal expansion and reduce focus shift as temperatures fluctuate during imaging sessions. Carbon fiber is renowned for its low thermal expansion properties, ensuring that the telescope maintains precise focus despite temperature variations. This stability is crucial for capturing high-quality, consistent imaging data throughout the night. Carbon fiber's ability to reach ambient temperatures quickly further enhances its performance. Unlike materials that retain heat, carbon fiber dissipates thermal energy efficiently, allowing the telescope to stabilize faster and be ready for optimal imaging conditions sooner.

Moreover, the carbon fiber truss design is extremely lightweight and rigid. This combination of lightness and strength ensures that the telescope's structure remains uncompromised, reducing any potential flexure that could affect image quality. The rigidity provided by carbon fiber supports the precise alignment of optical components, which is essential for producing excellent imaging data. By incorporating carbon fiber into the truss design, the CDK20 achieves a high level of thermal stability, structural integrity, and performance, making it an ideal choice for serious astrophotographers and observatory installations.

PlaneWave employs cutting-edge 3D printing technology to create lightweight and highly effective baffle tubes. By utilizing 3D printers, successive layers of material are precisely added to construct a baffle system tailored for optimal performance. This advanced manufacturing process allows for the creation of baffles with meticulously positioned internal stray light barriers, designed to minimize vignetting and maximize image contrast.

The precision of 3D printing technology ensures that each baffle is produced to exact specifications, enhancing the overall efficiency of the telescope’s optical system. Effective baffling plays a critical role in improving image quality by blocking unwanted stray light that can cause glare and reduce contrast. By integrating a carefully designed baffle system, PlaneWave ensures that their telescopes deliver superior clarity and detail in every captured image. In addition to their performance benefits, these 3D printed baffles are also lightweight, which contributes to the overall stability and balance of the telescope. The reduced weight helps maintain the structural integrity of the optical system without compromising its rigidity or alignment.

The incorporation of 3D printed baffles represents PlaneWave's commitment to leveraging advanced technologies to enhance the astrophotography experience. This innovative approach not only improves the telescope’s imaging capabilities but also exemplifies the dedication to quality and precision that defines PlaneWave’s products.

The CDK20 telescope incorporates a specially designed dovetail expansion joint, addressing the challenges posed by thermal expansion differences between carbon fiber and aluminum. This innovative feature ensures that the aluminum dovetail can expand and contract independently of the carbon fiber lower truss, preventing any stress or distortion that could affect the telescope’s performance.

Key Benefits:

• Thermal Compatibility: The dovetail expansion joint compensates for the differing thermal expansion rates of carbon fiber and aluminum. As temperatures change, the aluminum components can expand or contract without exerting pressure on the carbon fiber structure.
• Maintained Alignment: By allowing each material to move independently, the expansion joint helps maintain precise alignment of the optical components. This is crucial for preventing image distortion and ensuring consistent image quality throughout varying temperature conditions.
• Enhanced Image Quality: The prevention of stress-induced distortions means that astrophotographers can rely on the telescope to produce clear, accurate images. The expansion joint ensures that the optical tube remains stable, avoiding the subtle shifts that could degrade image sharpness and detail.
• Durability and Longevity: By mitigating thermal stress, the dovetail expansion joint contributes to the longevity of the telescope's components. It reduces the risk of material fatigue and damage over time, ensuring the telescope remains in optimal condition for longer periods.
• Seamless Integration: The expansion joint is seamlessly integrated into the telescope's design, maintaining the aesthetic and functional integrity of the instrument. It works silently in the background, allowing users to focus on their observations and imaging without concern for thermal issues.

The dovetail expansion joint exemplifies PlaneWave’s commitment to precision engineering and innovative design. By addressing the thermal expansion challenges inherent in combining different materials, this feature ensures that the CDK20 delivers uncompromised performance in all conditions. This thoughtful design consideration enhances both the durability and the imaging capabilities of the telescope, making it a reliable tool for astrophotographers and observatory installations alike.

The CDK20 telescope is equipped with cutting-edge dew prevention technology, ensuring uninterrupted observation sessions even in challenging environmental conditions. Internally wired with polyimide film heater pads and a temperature sensor, the CDK20 is fully prepared for seamless integration with the Delta-T system, accessible through the PlaneWave Interface 3 software.

Key Features:

• Polyimide Film Heater Pads: Strategically placed within the telescope's optical tube, polyimide film heater pads provide targeted heating to prevent dew formation on critical optical surfaces. By maintaining these components at optimal temperatures, the CDK20 ensures clear and unobstructed views of celestial objects, free from moisture-induced distortions.
• Temperature Sensor: A built-in temperature sensor continuously monitors the ambient temperature surrounding the telescope. This real-time data allows for precise control of the dew prevention system, ensuring that heating is applied only when necessary to maintain ideal viewing conditions.
• Delta-T Compatibility: The CDK20's internal wiring is specifically designed to interface seamlessly with the Delta-T system. Delta-T, accessible through the PlaneWave Interface 3 software, offers advanced control over dew prevention operations, allowing users to customize heating settings based on environmental conditions and observation preferences.

Benefits:

• Continuous Observation: By effectively preventing dew formation on optical surfaces, the CDK20 enables continuous observation sessions without interruption. Astrophotographers and observers can capture long-exposure images and conduct extended viewing sessions with confidence, knowing that their equipment is protected against moisture-related issues.
• Optical Clarity: Dew prevention technology ensures that the telescope's optics remain clear and free from moisture-induced distortions. This enhances image sharpness and detail, allowing users to capture stunningly crisp and precise astronomical images.
• User-Friendly Operation: Integration with the Delta-T system and PlaneWave Interface 3 software provides users with intuitive control over dew prevention settings. Customizable heating profiles and automated temperature monitoring simplify operation, allowing users to focus on their observations without the need for constant manual adjustments.

With its Delta-T-ready configuration, the CDK20 offers unparalleled dew-prevention capabilities, ensuring optimal performance even in humid or dew-prone environments. By combining advanced heating technology with seamless software integration, the CDK20 provides astrophotographers and observers with a reliable solution for maintaining optical clarity and maximizing observing time under any conditions.

The CDK20 telescope features a sophisticated cooling system designed to maintain thermal equilibrium and ensure consistent image quality under varying temperature conditions. Utilizing a combination of strategically positioned fans and precise control mechanisms, this system enhances the telescope's performance and minimizes image distortion caused by thermal fluctuations.

Cooling Fans Configuration:

• Backplate Fans: Three fans located on the backplate of the optical tube pull air through the telescope, directing it over the primary mirror. This airflow helps dissipate heat buildup around the primary mirror, promoting rapid cooling and reducing the risk of thermal distortion in images.
• Side Fans: Additionally, three fans positioned along the side of the optical tube blow air across the primary mirror's surface. This airflow creates a boundary layer of air that prevents temperature differentials from causing distortions in the optical path. By maintaining a consistent temperature across the primary mirror, these fans contribute to improved image stability and clarity.

Control Options:

• Manual Control: The telescope's cooling fans can be conveniently controlled via a switch located on the optical tube. This manual control option allows users to adjust fan speed and airflow direction according to their preferences and observing conditions.
• Software Integration: For enhanced convenience and precision, the cooling fans can also be controlled through the PlaneWave Interface 3 (PWI3) software. When paired with a PlaneWave Electronic Focus Accessory (EFA Kit), users can remotely adjust fan settings and monitor temperature levels in real time, ensuring optimal thermal management without the need for manual intervention.

Benefits:

• Rapid Thermal Equilibrium: The advanced cooling system enables the telescope to reach thermal equilibrium quickly, reducing cooldown times and minimizing thermal gradients across optical components. This ensures that the telescope remains stable and delivers consistent performance, even during extended observation sessions.
• Image Quality Preservation: By effectively managing temperature variations, the cooling fans help preserve image quality by minimizing the effects of thermal distortion. Astrophotographers can capture sharp, high-resolution images with reduced risk of thermal artifacts, allowing for more accurate analysis and interpretation of celestial phenomena.
• User-Friendly Operation: Whether through manual control or software integration, the cooling system offers intuitive operation and customizable settings to suit individual preferences and observing requirements. Users can easily adjust fan parameters and monitor temperature conditions, optimizing the telescope's performance with minimal effort.

The CDK20's advanced cooling system exemplifies PlaneWave's commitment to innovation and precision engineering. By incorporating strategically positioned fans and flexible control options, this system ensures optimal thermal stability and image quality, enhancing the observing experience for astrophotographers and enthusiasts alike.

Optical System Specifications