ZWO EFW 7×50 — filter wheel for 50 mm square filters
ZWO seven-position filter wheel for unmounted 50 × 50 mm square filters, sold separately. Check their thickness and the aperture of your mount.
CHF 440.10
Cooled monochrome astronomical camera for deep-sky imaging.
CHF 11'240.10incl. Swiss VAT
Part Number ZWO-A141355
Will be ordered for you
Timeframe: 10 days to 3 weeks
Estimated shipping: Between November 22 and 27, 2026
Cooled monochrome astronomical camera for deep-sky imaging.
The monochrome version captures light without a color filter array. To construct a color image, plan to take images with the appropriate filters and combine them during processing. It also allows you to work with narrow-band filters depending on the target. Active cooling helps stabilize long exposures and calibration. A compatible external power supply is required; the USB connection does not replace the power supply for the cooled module. Choose an operating temperature that the system can maintain throughout the entire session. Before mounting, check the thread, the distance between the sensor and the connector, and the space occupied by the filters or the optical splitter. The sensor alone does not determine the final field of view: the instrument, focal length, and any reducers also play a role. Take your calibration images using settings consistent with those used for observations. An astronomical camera provides no protection for solar observation: any use on the Sun requires a filter specifically designed for the instrument and properly installed.
Documentation and Compatibility: ZWO official data sheet.
The ZWO ASI461MM Pro is designed for deep-sky photography using long exposures: nebulae, galaxies, and clusters. Its cooling system (30 °C below ambient temperature) keeps thermal noise very low during exposures lasting several minutes. With its 3.76 µm pixels, it works well with instruments with focal lengths of approximately 400 to 800 mm (1 to 2″ per pixel). In monochrome mode, it can be used with LRGB or narrowband filters (Hα, OIII, SII) and remains effective under urban skies.
The Sony IMX461 is a medium-format sensor (43.9 × 32.9 mm, 102 Mpx): it is the largest sensor in our camera lineup, with 16-bit resolution. It requires a lens designed for an image circle of at least 55 mm.
The cooling system requires an external 12 V DC power supply; 3 A is recommended (5.5 × 2.1 mm connector, center positive). It is not included with the camera: we recommend the'Pegasus Astro 12 V 10 A power supply (2.1 mm plug). In the field, a Pegasus Astro unit like the Pocket Powerbox Advance It also powers the mount and the heating elements from a single source. Without a 12-volt power supply, the camera operates via the USB cable, but without cooling.
The camera's backfocus is 17.5 mm or 22.5 mm. Mount: M68 × 1. If using a corrector or reducer that requires 55 mm, make up the difference with extension rings, taking into account the filter wheel or filter drawer, if present.
For color photography with the ZWO ASI461MM Pro, you need a filter wheel: for this sensor, the ZWO EFW 7 × 2″ Filter Wheel is suitable. When it comes to filters, we recommend the Antlia line: the Antlia LRGB-V Pro Kit for galaxies and clusters, and filters Antlia Hα Pro 3 nm, OIII Pro 3 nm and SII Pro 3 nm For narrow-band nebulae, choose the 50 mm unmounted version.
With a ZWO OAG Optical Splitter and a small guidance camera like the ZWO ASI220MM Mini, you guide through the main telescope. A guide scope such as the'Askar 32 mm is the simplest alternative.
An anti-fog heating element is built into the front of the sensor window. It prevents fogging and frost when the sensor is cooled well below room temperature.
Yes: A built-in USB 2.0 hub allows you to connect a filter wheel, a guide camera, or a focuser directly to the camera, reducing the number of cables running to the computer.
The manufacturer's manual (in English) is available here: ZWO ASI461MM Pro Manual (PDF).
Here are a few accessories we've selected for this model, depending on your needs.
ZWO seven-position filter wheel for unmounted 50 × 50 mm square filters, sold separately. Check their thickness and the aperture of your mount.
Recommended ZWO splitter for the ASI461; compatible guide camera sold separately. Check the connections, focus, and prism position.
ZWO 12 V / 5 A power supply—optional if you don't already have a suitable power source. Check the connector, polarity, and the power requirements for your setup.
