What kind of mount is required for the Orion Optics UK CT16 OTA?
The CT16 optical tube weighs approximately 36kg and the rings add another 3.5kg, for a total weight of nearly 40kg before adding any imaging equipment. A heavy-duty, observatory-class German Equatorial Mount with a payload capacity of at least 50kg (110 lbs) or more is strongly recommended for stable imaging.
How does the CT16's 1/10 PV optics perform on planetary targets like Saturn?
The 1/10 PV wavefront accuracy provides exceptionally high contrast, which is critical for planetary observing. On Saturn, this means you will see not just the Cassini Division, but also subtler features like the Encke Gap (in good seeing), low-contrast banding on the planet's globe, and the delicate crepe ring. The image will be sharper and more stable than what a standard 1/4 PV optic can deliver.
Is the f/4 focal ratio of the CT16 good for deep-sky imaging?
Yes, an f/4 focal ratio is excellent for deep-sky imaging. It is considered a "fast" system, allowing you to capture faint details in nebulae and galaxies with shorter exposure times compared to a slower f/8 or f/10 system. You will need to pair it with a high-quality coma corrector to ensure sharp stars across the entire field of view.
What is the benefit of the carbon fiber tube on the CT16?
The carbon fiber sandwich tube offers two main advantages. First, it has virtually zero thermal expansion, which means the focal point does not shift as the temperature changes during the night. This is crucial for maintaining sharp focus over long imaging runs. Second, it provides a very high stiffness-to-weight ratio, ensuring the optical components remain perfectly aligned.
Does the Orion Optics CT16 come with a Zygo test report?
Yes. Every CT-range telescope from Orion Optics UK is supplied with a Zygo interferometry report. This document provides a detailed analysis of the primary mirror's surface accuracy, giving you documented proof that it meets the stringent 1/10 PV wavefront specification.
Why is active cooling important for a 400mm mirror like the one in the CT16?
A large 400mm mirror has significant thermal mass and can take hours to cool to the ambient air temperature. While it's cooling, it creates air currents inside the optical tube (tube seeing) that degrade the image. The integrated fan system on the CT16's 9-point mirror cell actively cools the mirror, drastically reducing this cooldown time so you can achieve sharp, stable images much faster.
