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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
Starlight Instruments 2.5" Base Flat w/ Leveling Screws

Starlight Instruments 2.5" Base Flat w/ Leveling Screws

by Starlight Instruments
SKU SI-BA25FL
$140.00 - $140.00
$140.00
$140.00 - $140.00
$140.00
Price Match Policy!
  • Provides a flat mounting surface for custom telescope builds
  • Integrated leveling screws for precise focuser collimation
  • Designed specifically for the 2.5" Feather Touch Focuser
  • Requires Starlight Instruments A25-2003-1 Tube Adapter Ring
  • Threads into the M95x1 female thread on the adapter ring
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  • Description
  • FAQ
  • Downloads
  • Warranty

  • Starlight Instruments 2.5" Base Flat w/ Leveling Screws

    The Starlight Instruments 2.5" Flat Base is the essential mounting component for attaching a 2.5" Feather Touch Focuser to a custom flat-surface telescope tube, such as a square-tube Newtonian or custom mounting plate. This base connects to the required A25-2003-1 tube adapter ring, utilizing its M95x1 threads to create a secure, precisely adjustable foundation for your optical train.

    A Solid Foundation: Precision Collimation with Leveling Screws

    This base provides more than just a mechanical connection; it is a tool for optical alignment. The integrated leveling screws allow you to make fine adjustments to the focuser's tilt, ensuring its drawtube is perfectly perpendicular to the telescope's optical axis. This capability is critical for astrophotography, as it eliminates field tilt and ensures sharp, round stars across the entire imaging sensor.

    M95x1 Threaded Interface for the 2.5" Feather Touch Focuser

    This component is designed as part of the Starlight Instruments modular focusing system and is not a standalone part. It is specifically engineered to thread into the Starlight Instruments A25-2003-1 tube adapter ring, which features a female M95x1 thread. This ring, which must be purchased separately, then holds the 2.5" Feather Touch Focuser, creating a rigid and collimatable assembly for custom telescope builds.

  • What is the purpose of the leveling screws on the Starlight Instruments 2.5" Flat Base?

    The leveling screws are for collimation. They allow you to make micro-adjustments to the tilt of the entire focuser assembly. This ensures the focuser's mechanical axis is perfectly square to the optical axis of your telescope, which is essential for achieving a flat focal plane and sharp stars from edge to edge in astrophotography.

    Which focuser is this Starlight Instruments flat base designed for?

    This base is designed exclusively for use with the Starlight Instruments 2.5" Feather Touch Focuser. It is part of the mounting system that secures this specific focuser to a custom telescope tube or mounting surface.

    Do I need other parts to mount my 2.5" Feather Touch focuser using this base?

    Yes, absolutely. This base is one component of a larger assembly. To mount your 2.5" Feather Touch Focuser, you will also need the Starlight Instruments A25-2003-1 Tube Adapter Ring, which is sold separately. This base threads into that adapter ring, and the adapter ring holds the focuser.

    How does the 2.5" Flat Base attach to a custom telescope tube?

    This base provides a flat surface with mounting holes. You would typically drill a corresponding pattern of holes into your flat telescope tube wall or adapter plate. The base is then secured to the tube using screws (not included), creating a solid mechanical foundation before the focuser and adapter ring are installed.

    Is the Starlight Instruments 2.5" Base for a curved or flat telescope tube?

    As the name implies, this is a Flat Base. It is intended for mounting on flat surfaces, such as the side of a square-tube Dobsonian, a custom instrument plate, or other bespoke telescope designs that do not have a curved tube wall.

    Can I use this base without the A25-2003-1 adapter ring?

    No. The 2.5" Feather Touch Focuser does not attach directly to this base. The base threads into the A25-2003-1 adapter ring via an M95x1 thread, and the adapter ring, in turn, holds the focuser. The adapter ring is a required, non-optional component for using this base.

  • Starlight Instruments 2-Year Warranty