Low-Profile 1.25" Focuser for Newtonian on 3.5" Base


Low-Profile 1.25" Focuser for Newtonian on 3.5" Base

Regular price
$ 229.90
Sale price
$ 229.90
Unit price

This item is out of stock but you can place an order now and we’ll ship when it becomes available.


The Low Profile 1.25" Focuser for Newtonian, 3.5" Base, is a high-precision, pin-and-groove type helical focuser. The 3.5" base provides for replacing larger focusers with a center-to-center hole-spacing of 2.75". The draw-tube does not rotate.

Accessories that take up back-focus, such Lumicon's popular 1.25" Multiple Filter Selector, can be used with ease and convenience. The high-precision, smooth focusing brings out the very best in your telescope's optics. The low-profile design quickly and easily converts your standard Newtonian to a camera-ready telescope. The U-groove base aligns and sits flush on any telescope tube with a radius of 4.5" or larger.


  • Focuser Minimum Height Above Tube* .75" (for 4.5" radius tube), 2" (for flat-base mounting)
  • Turns Ratio: 2 per inch
  • Travel: 1"
  • Resolution/Backlash: < 0.0005"
  • Image Shift: Negligible
  • Reverse Action: Negligible
  • "Stiction:" Negligible
  • Footprint: 3.5" Square
  • Mounting Hole Pattern: Square; 2.75" center-to-center
  • Min/Max focuser hole diameter: 1.5"/3.3"
  • Operating Range: to 20°F/- 7° C
  • Maximum Recommended Load: 3 lbs
  • Mounting Hardware: 8-32, Included

*Precise minimum depends on radius of tube.

Note: Visual use of the Low Profile Focuser requires either the Lumicon 1.25" Multiple Filter Selector, LF5010, or a 1.25" extension tube, such as the Lumicon LA1020.

Personal Upgrade Path

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