Software Bisque Paramount Taurus Model 400 Equatorial Fork Mount

The Paramount Taurus 400: An Observatory Mount for 17-Inch Telescopes

The Paramount Taurus 400 is designed for permanent observatories housing large-aperture instruments like Schmidt-Cassegrain or open-truss telescopes up to 17 inches (0.4 m). By cradling the optical tube assembly between two fork arms, it needs no meridian flips and has no dangling counterweights.

This mount suits imagers who want to follow a single target for many hours: Taurus forks allow uninterrupted horizon-to-horizon imaging.

Tracking Up to 6 Hours Past the Meridian

The equatorial fork is the engineering core of the Taurus 400. This design allows the mount to track an object continuously across the entire sky, including for up to 6 hours past the celestial meridian. This capability fundamentally changes how you can plan an imaging session, removing the time constraints imposed by a future meridian flip.

For visual observers, the fork gives exceptionally comfortable access to eyepieces. For imagers, an automated sequence can run through the meridian without stopping for a flip.

150 lb. Capacity for OTAs from 14 to 22 Inches in Diameter

The Taurus 400 supports a total instrument capacity of 150 lb. (70 kg), providing a rigid foundation for heavy optical systems and their associated imaging trains. The fork arms are machined from solid aluminum and can accept optical tubes with an outer diameter ranging from 14 inches (36 cm) to 22 inches (55 cm). The fork can carry a single OTA or multiple OTAs within that range.

To ensure optimal balance, the mount features a counterweight system to correct for asymmetries in the optical tube or off-center payloads. This maintains the pointing accuracy and tracking stability of the system even when loaded with complex instrument packages. For maximum flexibility, an optional Scope Rail System allows you to mount and adjust instruments along the optical axis, simplifying the process of changing or balancing your equipment.

A 776-Tooth RA Gear and Zero-Backlash Worm Drive

The drive train of the Taurus 400 is built around research-grade components for precision and reliability. The right ascension axis is driven by a massive 11.5-inch (29 cm), 776-tooth aluminum gear, while the declination axis uses a 10-inch (25 cm), 420-tooth gear. These large gears provide the fine control necessary for smooth, accurate tracking.

Motion is transferred via a belt-driven, spring-loaded worm gear system that produces virtually zero backlash. This clutch-free design ensures that the mount's precise TPoint-assisted pointing accuracy is maintained at all times. Power is supplied by single-stack NEMA 23 brushless DC servomotors, which deliver consistent torque and quiet operation for all-night, every-night reliability.

7 Arcsecond Native PE and Optional 0.1 Arcsecond Absolute Encoders

Out of the box, the Paramount Taurus 400 has a mechanical peak-to-peak periodic error of 7 arcseconds or less. After a one-time software training session, this error is typically reduced to 1 arcsecond or less, a level often smaller than atmospheric seeing.

As an option, the mount can be configured with optional on-axis Renishaw absolute encoders. These encoders provide better than 0.1 arcsecond resolution on each axis, effectively eliminating periodic error and the need for homing routines. They operate in temperatures as low as -40 °C.

30 Arcsecond RMS All-Sky Pointing with TPoint and ProTrack

The Paramount's pointing and tracking accuracy is rooted in its sophisticated software. Using TheSky's integrated TPoint module, you create a detailed model of your entire telescope system, mapping out repeatable errors across the sky. This process achieves an all-sky pointing accuracy of 30 arcseconds RMS or less, ensuring any target you select will land squarely in the field of view.

Once the model is built, ProTrack uses it in real-time to continuously correct for system-wide tracking errors. This goes far beyond simple periodic error correction, compensating for atmospheric refraction, polar misalignment, and even tube flexure as the telescope moves. This active correction is what enables the Taurus 400 to achieve unguided exposures of 5-10 minutes, with many users reporting successful 20-minute exposures under good conditions.

MKS 6000: USB-C, Ethernet, and Wi-Fi Control

The MKS 6000 is the advanced telescope control system at the heart of the Taurus 400. It offers modern, reliable connectivity through a choice of USB-C, Ethernet, or a built-in Wi-Fi hotspot, allowing you to control the mount in whatever way best suits your observatory setup. All electronics and through-the-mount cabling are housed inside the mount for protection and clean cable management.

The instrument panel provides three high-power XT60 ports and a pass-through Ethernet port, simplifying power and data connections to your camera and accessories. In the event of an abrupt power loss, the AutoHome feature ensures the mount can quickly re-establish its orientation after a brief homing process, preserving the integrity of your pointing model.

TheSky Universal Bundle on up to 6 Computers

Every Paramount Taurus 400 includes the full TheSky Universal software bundle. This is not a lite version; it is a complete, integrated observatory control application that includes TheSky Professional, TPoint, Cameras+, Domes, Multi-OS+, and Weather modules. This single program provides unified control over your entire imaging system, eliminating the complexity and potential conflicts of running separate applications for mount, camera, and dome control.

The software runs natively and identically on Windows, macOS, and Linux (x86_64 and ARM64), and it appears and operates identically on each. A single license can be installed on up to six different computers, allowing you to operate your observatory from a dedicated control computer and process your data on multiple other machines without additional cost.

Assembly and Polar Alignment from 0° to 58° Latitude

The Taurus 400 is designed for two-person assembly in about an hour. The mount breaks down into five separate components, making it manageable to transport and install. It requires the dedicated Taurus 400 Pier (sold separately) for proper stability and alignment, which connects to the mount's integrated 14 x 12 inch base.

The mount features a built-in ratcheting altitude mechanism that allows adjustment from 0° to 58° latitude, and Bisque can manufacture a custom mounting pedestal for higher latitudes. The mechanical azimuth adjustment provides a range of ±2.5°. Once coarsely aligned, TheSky’s Accurate Polar Alignment routine, combined with the mount's fine-tuning controls, ensures a precise alignment to the refracted celestial pole.

3.5° Per Second Slewing with a 220W Power Supply

The Taurus 400 can slew at a maximum speed of 3.5° per second in both axes, allowing it to move rapidly between targets. This speed helps maximize data collection time during a night by minimizing the time spent repositioning the telescope. The factory default slew rate of 80% maximum is recommended for most payloads and temperatures.

The system is powered by an included 48V DC power supply, capable of delivering a maximum of 221W. The NEMA 23 brushless DC servomotors deliver consistent torque at all slew rates, and Paramounts can slew or track several foot-pounds out of balance, though good balance is always recommended. Near or above the rated capacity, or in the cold, slower slews and lower acceleration are required.

A 142 lb. Mount Designed for Robotic Operation

Weighing approximately 142 lb. (65 kg), the Taurus 400 is a substantial piece of engineering built for stability. Its clutch-free, zero-backlash design and internal cabling are all geared towards reliable, repeatable, and automated operation. From the moment of power-on, the system provides clear LED and audible feedback for startup, homing, and error status.

Your first night with the Taurus 400 involves assembling the mount on its pier, attaching your OTA, and performing an initial balance. You then connect to TheSky Professional, run the homing sequence, and begin building your first TPoint model. This calibration process is the key to the mount's 30 arcsecond RMS pointing and ProTrack-assisted tracking, turning your large telescope into a precision robotic instrument.

Taurus 400 Fork vs. German Equatorial Mounts: The Meridian Flip Advantage

While a German Equatorial Mount (GEM) offers greater flexibility for swapping between different telescopes, its defining operational drawback is the mandatory meridian flip. The Taurus 400's fork design is engineered specifically to solve this problem.

• Uninterrupted Tracking: A fork mount can track an object continuously from its rise to its set. This is critical for scientific applications like photometry and for deep imaging projects where data consistency over many hours is paramount.
• Reduced Complexity: By removing the meridian flip, you eliminate a primary point of failure in an automated imaging sequence. This simplifies scripting, improves the reliability of remote observatories, and removes the risk of a pier collision during a flip.
• Instrument Dedication: The primary trade-off is that a fork mount is dedicated to a specific instrument or a narrow range of instrument sizes. A GEM with a universal dovetail saddle can easily accept a wide variety of OTAs, making it a more versatile choice for users who frequently change telescopes.