Baader Planetarium #25C T2 7.5mm Extension Ring

Baader Planetarium #25C T2 7.5mm Extension Ring

Getting the focus right is one of the most common challenges when building an optical train. The correct spacing between components determines whether your image is sharp across the entire sensor or eyepiece field. The Baader Planetarium T2 extension ring, 7.5mm solves this problem simply and reliably. Its compact length makes it ideal for fine-tuning your setup when longer adapters are simply too coarse an adjustment.

PTFE-coated thread for smooth, precise operation

The ring features a black PTFE-coated surface that serves two important purposes at once. First, it ensures smooth, precise thread engagement with no binding or excessive friction. Second, it minimises unwanted internal reflections inside the optical train.

The result is high contrast in your images - even when observing fine planetary detail or faint deep-sky objects. The build quality reflects Baader Planetarium's long tradition of manufacturing adapters to tight tolerances.

A universal T2 adapter for almost any setup

The T2 thread is the de facto standard in astronomy. This ring fits naturally into virtually any modern or older optical chain. Typical applications include:

• Connecting a DSLR or astro camera to a refractor or reflector telescope
• Combining with filter drawers or filter sliders
• Fine-tuning focuser extension tubes with Barlow lenses
• Achieving exact focus distance when other components fall just short

Keep this ring in your accessory box and you will always have a quick, elegant solution ready whenever your optical train needs a small but critical adjustment.

Technical specifications