Starlight Instruments, Inc.

 

Quality Focusers and Accessories for the Amateur Astronomer

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RECOMMENDED MODELS FOR
REFRACTORS 2.5" Travel

2.0'' Diameter - Low Profile 2.5'' Travel
Model FTF2025 Model FTF2025CR
Base Model
$285.00 $300.00
Model FTF2025B (Recommended) Model FTF2025BCR (Recommended)
$320.00 $335.00
Standard Features
  • Ultra-smooth coarse/fine focus knobs (10:1 Ratio)
  • Durable hardened stainless steel, steel, and aluminum construction
  • Standard Draw Tube with nylon-tipped stainless steel set screws (gentle on eyepieces)
  • 52mm threaded Draw Tube to accommodate filters
  • Glare resistant black internal baffling
  • Anodized aluminum fine focus knob
  • Ultra-Low backlash system for accurate control
  • Sleek aesthetic design

Eyepiece Adapters (1.25" to 2.00" Adapter with 48mm threads for filters)

$35
$35
$35
FEATURES & EQUIPMENT DETAILS
Draw Tube Compression Ring

Photo Featuring Brass Compression Ring

We have recently introduced a new design that incorporates a brass compression ring. This ring acts as a buffer between the thumb screws and your eyepieces so that it will not mar them. The Compression Ring also has improved holding power over the nylon tipped screws.

NOTE: There are two thumb screws on our draw tubes with the Compression Ring. The right screw is used for 2” eyepieces and the left screw is used for 1 ¼ eyepieces.
The left thumb screw is nylon tipped and can also be used in addition to the right thumb screw. When used with our 1 ¼ -2 inch zero length adapter, the left thumb screw is used to hold the 1 ¼ eyepiece in place.

NOTE:
1.All draw tubes are machined with internal anti-reflection baffling.

2.All draw tubes also have a 52 mm thread machined on the back surface. This will accommodate permanent or semi permanent filters if desired, such as Light Pollution Filters, clear filters for dust protection, etc. Step down adapters that reduce the 52 mm thread to 48 mm threads are available through larger camera stores. 

Internal Brake System (IBS)


In some Newtonian telescopes the brake option may be needed. If the draw tube motion is not horizontal and has a vertical component, the brake option should be considered. This may be needed if heavy eyepieces or accessories are used that may result in the draw tube to drift from its set position. This is necessary because our focusers are so smooth and move so freely. Although they will hold some weight in the vertical position without drifting (generally about 1 lb.), if more control is needed the IBS should be considered.

The brake consists of a lever arrangement internal to the pinion block. By adjusting the thumb screw on the pinion block this lever presses a friction pad onto the pinion thereby increasing the torque that is needed to turn the focus knobs. If the thumb screw is turned all the way in, the pinion shaft and the draw tube will be locked. Opposite this thumb screw is a small set screw that is factory set and should not be adjusted by the customer.

Original Low Profile Adapter

Our Low Profile adapter is designed to add zero length when inserted into the 2 inch draw tube.

The thumb screws on the draw tube can be used for holding the 1 ¼ adapter and the eyepieces simultaneously. This adapter has no flange and works well with larger eyepieces.

  • All 1 ¼ eyepiece adapters are interchangeable with our focuser draw tubes and come with a brass compressing ring.

  • All 1 ¼ eyepiece adapters have a 48 mm thread machined in the back to accommodate 2 inch filters.
Easy Grip Adapter

Our Easy Grip Adapter is the same as our Original Low Profile Adapter but with an additional raised flange that adds ¼ of an inch.
For most eyepieces this flange does not interfere and allows gripping the adapter for easier removal.

 

  • All 1 ¼ eyepiece adapters are interchangeable with our focuser draw tubes and come with a brass compressing ring.

  • All 1 ¼ eyepiece adapters have a 48 mm thread machined in the back to accommodate 2 inch filters.
Note: For some applications such as 1 ¼ inch diagonals the flange will prevent the diagonal from seating flush with the adapter.
Standard Adapter
Generally used on refractor style telescopes, but can be used with Newtonians in certain situations depending on where the focal point resides.

Our Standard Adapter can be used where zero length is not a consideration. It uses a thumb screw on the body of the adapter to hold the 1 ¼ eyepieces and the adapter is held in place by the thumb screw/s in the draw tube.

  • All 1 ¼ eyepiece adapters are interchangeable with our focuser draw tubes and come with a brass compressing ring.

  • All 1 ¼ eyepiece adapters have a 48 mm thread machined in the back to accommodate 2 inch filters.