ZWO Monochrome Astro Camera ASI461MM Pro cooled, Sensor D=55 mm

ZWO ASI461MM Pro -professional CMOS monochrome medium format camera, cooled

The ZWO ASI461MM Pro is a 100 megapixel camera for astrophotographers who expect top class results. The sensor has a similar dynamic range as a CCD sensor, with unequally higher sensitivity. The camera can be used on all well-corrected telescopes and is a true lightweight for its size at only 910 grams.

The sensor has a 16-bit ADC with 65536 stages, back-illumination technology, and high quantum efficiency, providing great performance for deep-sky imaging, milky way imaging, and research.

Low readout noise, no amplifier glow and no visible fixed-pattern noise further enhance the images.

Medium format with 100 megapixels

The 100-megapixel Sony IMX461 sensor already offers medium format with 44x33 mm image size (approx. 55 mm diagonal) and a high resolution of 11656x8750 pixels. The 3.76-µm pixels have a full-well capacity of 50.3 ke. In 2x2 binning mode, you get an even larger full-well capacity of 198 ke and a larger pixel size of 7.5 µm * 7.5 µm.

Back illumination technology

Sony´s back-illuminated CMOS image sensor improves sensitivity and noise reduction - the key factors to enhancing image quality, while radically realigning their fundamental pixel structure from front-illumination to back-illumination. It has retained the advantages of CMOS image sensors such as low power consumption and high-speed operation.

The backside exposure improves the light absorption and increases the amount of light at the same time. This allows significantly shorter exposure times and leads to an improved quantum efficiency of up to 91% - maximum of astromomical CMOS cameras.

Sony has newly developed a unique photo-diode structure and on-chip lens optimized for back-illuminated structures, that achieves a higher sensitivity and a lower random noise without light by reducing noise, dark current and defect pixels compared to the conventional front-illuminated structure.

Zero amp glow

Traditional CMOS sensors produce a weak infrared light source during operation quite often seen in the corner of uncalibrated images as the tell tale signs of "amp glow". As the ASI461MM Pro uses zero amp glow circuitry, you won´t have to worry about amp glow even when using high gain, long exposure imaging.

Anti-dew heater integrated

The ASI461MM Pro comes with the polyimide heater that can avoid any dew problems.
The anti-dew heater, which fits completely onto the protective window, heats it up slightly to prevent condensation problems.
The power of the anti-dew heater is approx. 5 W. It can be turned off in the software to save power.

Important: external power supply required!

This camera requires 1 amp even in uncooled operation, which is a problem for USB sockets on computers, because they are only rated for 900 mA (0.9 A).
Stable operation of the camera is therefore only possible with an external 12 V power supply.

Optimal support by Teleskop-Service before and after purchase:

We work with the cameras ourselves and can offer you optimal advice. Which camera matches your telescope, how do you achieve optimal adaptation? Teleskop-Service is one of the biggest ZWO dealers. Due to our contacts, we offer best possible service also after purchase.

Practical tip from TS: Storage of cameras and accessories

Especially in our latitudes, the nights are often very humid. This humidity condenses on your camera, eyepiece or filter when they come into the warm interior of the apartment. Especially cooled cameras are affected by this. Quickly a photo session is over because the sensor ices up.

Good storage is an important prevention against dew and also extends the life span.
After use, put the camera immediately into the TS Protect Case and add some silica gel. During storage, the silica gel will suck the moisture out of the camera. At the same time, the penetration of humid room air is prevented. Dry storage even allows the small dry tablets in cooled cameras to partially regenerate. Your camera or accessories are always ready for you in optimal condition. You can find the silica gel and the case in our product recommendations.

The cameras are not airtight, so if the camera remains on the telescope, it is exposed to moisture. The small amount of desiccant in the camera can protect the sensor and the inside of the protective glass from moisture for the duration of the exposure, but not for days on end. Moisture problems can be the result. A simple trick is to stretch a plastic bag around the focuser to which the camera is attached so that no air can get in. Silica gel is placed in a small cloth bag inside the plastic bag. This will also create a "dry climate zone" for the camera on the telescope. This allows you to leave the camera on the telescope for a few days for an imaging session lasting several days.

In the medium and long term, however, this is no substitute for proper storage in an airtight case with silica gel.

Downloads, drivers:

ZWO provides software and drivers online for free download.

Software and drivers for all ZWO cameras

Frequently asked questions about ZWO cameras:

The FAQ area is constantly updated by ZWO, here you will find answers to many questions.

FAQ about ZWO cameras

ZWO Users Forum

Manuals for ZWO products:

The manuals page is constantly updated by ZWO, here you can find user guides for ZWO products.

Link to the manuals (the one for this camera will appear)

How to clean my ZWO camera:

The manufacturer provides a manual that covers how to clean an ASI camera and regenerate the desiccant tablets: Please click here.

How can I put a filter in the light path?

The sensor has a diagonal of almost 55 mm, so filter drawers or filter wheels for round filters of 50 mm diameter are not sufficient.

ZWO has announced a filter wheel specifically for the ASI461MM Pro, but there is another way: The Baader UFC system offers an insert for unmounted filters of the dimension 50 mm x 50 mm and an adapter with external thread M61x1. This is telescope side, but fits into the camera. With a camera adapter with internal thread M68x1 for the telescope side you can assemble a filter adapter with M68 threads, which can be inserted into a working light path.

Question:
Will my Pro camera work without extra power supply if I don´t turn on the cooling?

Answer from Teleskop-Service:
No, the current Pro cameras always require extra power supply, even without cooling.

Safety informations: PDF Download