Tele Vue Tunable Top with 1.25" Adapter

The Heart of Coma Correction: The Micro-Adjustable Mechanism

A Paracorr's performance is entirely dependent on the precise distance between its lenses and your eyepiece's focal plane. The Tunable Top's helical mechanism allows you to dial in this distance with exacting precision. As you twist the upper section, it smoothly extends or retracts, changing the spacing without rotating the eyepiece, so your target remains perfectly framed.

This fine control is not a "set and forget" feature. Every eyepiece design has a unique focal plane position. This device empowers you to find the specific sweet spot for each eyepiece in your collection, ensuring that whether you are using a Plössl or a wide-field Nagler, you are achieving the highest level of coma correction the Paracorr can deliver.

Repeatable Performance with the Engraved Reference Scale

Finding the perfect setting for an eyepiece is only half the battle. The Tunable Top features a clearly laser-engraved millimeter scale on its body, allowing you to note and record the optimal position for each of your 1.25" eyepieces. This simple but critical feature eliminates guesswork during your observing sessions.

Once you chart your eyepieces, you can switch between them in the dark with confidence, quickly dialing the Tunable Top to the predetermined mark for each one. This workflow saves precious observing time and guarantees you are getting the same sharp, edge-corrected views every single time you insert that eyepiece.

Secure and Safe Mounting with a Brass Clamp Ring

Standard set screws can mar the barrels of your expensive eyepieces, leaving unsightly and potentially damaging gouges. The Tele Vue Tunable Top incorporates a non-marring brass clamp ring. When you tighten the lock screw, this internal ring compresses gently and evenly around the eyepiece barrel.

This design provides a more secure, concentric grip than a single screw, preventing eyepiece tilt that can degrade optical performance. Most importantly, it protects your investment, ensuring the barrels of your eyepieces remain in pristine condition no matter how many times you use them.

Seamless Integration with the Paracorr Type-2 Interface

This Tunable Top is designed specifically for the Tele Vue Paracorr Type 2, ensuring a perfect, rigid fit. It threads directly onto the main optical body of the Paracorr, creating a solid, flex-free connection that becomes an integral part of the optical train. This robust mechanical link is critical for maintaining optical alignment, especially when using heavier eyepieces or cameras.

Add Contrast with Integrated 1.25" Filter Threads

Conveniently located at the base of the eyepiece barrel holder are standard M28.5x0.6 threads. This allows you to attach any 1.25" filter, such as a nebula or light pollution filter, directly to the Tunable Top. Placing the filter here, before the eyepiece, ensures it is a permanent part of your Paracorr setup, simplifying your workflow when you switch eyepieces.

A Necessary Upgrade, Not a Luxury Accessory

For the owner of a fast f/3 to f/5 Newtonian reflector, coma is the single greatest barrier to achieving wide-field views with sharp stars edge-to-edge. While the Paracorr Type 2 provides the optical correction, the Tunable Top provides the essential mechanical control to make that correction perfect for your specific eyepieces.

Without it, you are using the Paracorr at a generic setting that is a compromise for most eyepieces. The only genuine trade-off is the initial time spent calibrating your eyepiece collection. Once done, this tool transforms your observing from a series of optical compromises to a repeatable, optimized experience every night.