Feather Touch 3.5" Diameter Dual Speed Focuser Kit, 4.5" DTT*(incl. Brake, End Cap and Tube Adapter Options)
The 3000 Series STARLIGHT INSTRUMENTS Feather Touch 3.5" focuser incorporates advanced features that are ideal for applications which demand precision imaging while also managing a heavier weight capacity than SI 2 inch models. A factory-installed Integrated Teflon Collar provides a bind-free 360 degrees of smooth focuser rotation. This Integrated Collar allows attachment of Tube Adapters, Bases, and other accessories via a 109mm x 1mm male thread.
*Draw Tube Travel
The thumbscrew on the focuser makes rotating easy relative to the optical tube assembly. Additionally, the thumbscrews on the collar make detaching the focuser a quick and easy task.
The 3000 series focusers come with Starlight Instruments' Fine Focus Reduction Unit which allows very accurate focusing. It is typically a 9:1 planetary reduction assembly that makes focusing extremely precise and easy. Starlight is the original developer of this type of system for telescope use and have been making and improving these for longer than any other manufacturer. These units have undergone continuous improvement and are, quite simply, the best in the industry.
About the Feather Touch Internal Brake System...
Because the focuser is so smooth in operation and moves so freely, it can only hold a limited amount of weight without drifting out of focus when the focuser drawtube is not horizontal and has a vertical component. The focuser therefore contains an adjustable tension internal brake system to allow astrophotography and visual use with heavy eyepieces without the possibility of the focus shift.
The brake consists of a lever arrangement internal to the pinion block. Adjusting the thumbscrew on the pinion block causes the lever to press a friction pad onto the pinion. This increases the torque needed to turn the focus knobs. If the thumbscrew is turned all the way in (only 1 to 1½ turns), the pinion shaft and the drawtube are locked in position for long exposure astrophotography.
Visually, partial tightening of the internal brake offers a virtually infinite range of braking force to accommodate various eyepiece weights. Moderate finger-pressure tightening of the drawtube tension screw allows the lifting capacity to be adjusted up to a nominal maximum of five pounds, although greater payloads are possible by further tightening the tension screw.
- Precision hardened stainless steel fine pitch helical pinion
- Extra wide fine pitch rack for extremely accurate positioning and feel
- Focuser is fully rotatable relative to telescope position
- Locking ring for rotation feature allows on the fly adjustment and locking
- Heavy duty 10:1 reduction unit
- Tension brake adjustment for custom load control and locking capability
- Reversable pinion housing/fine focus factory set on right side
- Course focus on both sides of pinion housing
- Interchangeable end caps
- Machined (sharp edge type) internal light baffles for best low reflectivity properties
- Laser scibed scale on both sides of the draw tube (115mm with 1mm resolution)
- Precision manufactured from the best materials available and built for long life and trouble free operation. All alumimum parts are anodized and all other non alumimum parts are corrosion resistant stainless steel. No short cuts and no compromise in the design!
|Name||Starlight Instruments - Feather Touch 3.5" Diameter Dual Speed Focuser Kit, 4.5" DTT, Brake, End Cap and Tube Adapter Options|
|Custom Stock Status||Available - Ships in 3-5 Days|