SVBONY SV164 2″ Dark Frame Filter

Product Overview

The SVBONY SV164 is a 2″ dark frame filter: an opaque, metal filter that blocks light from reaching the sensor. Placed in a filter wheel, it lets a camera without a mechanical shutter record dark calibration frames without removing the camera or capping the telescope. It is 1 mm thick with a standard M48 x 0.75 2″ thread.

Who It's For

This is a good match if you image with a CMOS or CCD astronomy camera and a 2″ filter wheel and want to automate dark frames at the end of a session, for example as part of a scripted capture sequence.

Key Features & Design

• Dark frame imaging filter: blocks light so the camera records only its own thermal signal and hot pixels.
• 2″ format, M48 x 0.75 thread: fits a 2″ filter wheel position.
• 1 mm thick, metal construction.

Recommended Uses

• Dark frames taken from a filter-wheel slot, with the camera left in place.
• Automated calibration at the end of an imaging sequence.

Compatibility and Accessory Notes

• Fits: 2″ filter wheels and filter holders with M48 x 0.75 threads.
• Thickness: 1 mm.

Good to Know Before You Order

• Imaging only: it passes no light, so it has no application for visual observing.
• Ambient light: for the cleanest darks it is worth also keeping stray light away from the rest of the train, since the filter covers the optical path only at the wheel.

Frequently Asked Questions

Is it difficult to set up?

No. It threads into a 2″ filter-wheel position like any other 2″ filter; set that slot as your dark position in your capture software.

Why use a dark filter instead of a lens cap?

The filter wheel can switch to it automatically, so darks can be captured without anyone at the telescope.

Does it work with 1.25″ wheels?

No. It is a 2″, M48 x 0.75 filter.

Bottom Line

In short: a 1 mm, 2″ M48 opaque filter that turns a filter-wheel slot into a shutter for unattended dark frames.