I got to shoot the Milky Way with the new OM System OM-3 Astro camera, and here's what I found out about this limited-edition specially-modified camera

I was really excited when I heard that OM System had produced an Astro version of its OM-3 camera. Mirrorless and DSLR cameras modified for astrophotography have been released regularly by Canon, Fujifilm, Nikon and Olympus in the past ten years. But few of them stay on sale for long. Released as special editions, they disappear almost as soon as they appear - a bit like a twinkling star!

The OM System OM-3 Astro has particular interest as the OM-3 already has a few features that make it an appealing option for astrophotography, such as its Starry Star AF system. But the appeal of the special addition is the modified sensor that is optimized to see the red Hydrogen Alpha (Hα) part of the spectrum, which is crucial for the best photos of nebulae and dying stars.

Historically, this kind of narrowband imaging has not been for the faint-hearted. Previously, obtaining an astro camera meant you modified a camera's sensor (in a similar way to an infrared conversion), to reveal the hydrogen alpha emission. But this came at the expense of rendering your camera warranty void and even run the risk of ruining the camera. A dedicated, out-of-the-box astro camera avoids these worries - so it is great to see this new OM System option.

It is worth pointing out that even with the OM-3 Astro, you are still going to need a star tracker. A budget option that I have tested and recommend is the MoveShootMove Nomad. A star tracker aligned to the celestial pole and coupled with dark skies, will reveal this nebulosity as glowing regions of deep red, crimson light. Areas of emitting hydrogen alpha gas (656nm) are formed by energized ultraviolet radiation, creating ionization of surrounding gas clouds. Although not directly visible to the unaided eye, the OM-3 Astro's converted sensor reveals another layer to the universe behind the lens of an astro image.

The camera comes out the box with a modified Infrared Cut Filter. Custom presets are selected by using the presets: CL 1 & 2 for different visual effects. CL 1 preferable for Ha emission; CL 2 for starry nightscapes.

For the short time, DCW had the use of the OM-3 Astro camera, I was ongly able to test for a handful of nights with far from ideal conditions. With the waxing gibbous moon (and the unpredictably of the British weather). But once the moon had set, I had approximately 30-minutes to trial and error the camera to capture the galactic core over the dark skies of The Mendip Hills Area of Outstanding Natural Beauty (AONB).

With a $2,499/£1,899 price tag, this option is a more affordable option compared to astro-camera options that have been released before. It is important to note that it does not have a full frame sensor, using a Micro Four Thirds sensor which around a quarter of the size

The camera is weather-sealed. It is reassuring to know if imaging for prolonged periods of time, condensation will not affect image performance internally or within more rugged environments. A lens heater however, is highly recommended for unexpected environmental conditions that may result in condensation on the lens (such as the CooWoo Lens Heater or the one from MoveShootMove).

I recommend a good quality lens when using this camera – one with greater light gathering and glass – such as the M.Zuiko Digital ED 7-14mm f/2.8 PRO lens – notot only to reduce coma and vignetting, but to result in an overall sharper image and greater light gathering in a short space of time. My tests, unfortunately, were made using the less-than-ideal M.Zuiko 17mm f/1.8. Shooting wide has the benefit of capturing a greater coverage of sky for more dynamic, wide-angle/fisheye perspectives of the night sky. The camera can also be used with telephoto lenses for images of galaxies and nebulae to reveal the Hydrogen-Alpha emission.

Starry Sky AF (incorporated into the OM-3 Astro) applies a special algorithm to focus on stars, even for smaller, dimmer pinpoint sources of light. This is a great consideration for those who may be less familiar with astro focusing and processes in low-light environments. Although this AF option as good, my personal preference is to manually focus stars on the stars for greater manual control. But equally good to know the technology is there for ease.

The 3-inch rear LED monitor is optimized for low-light environments and makes focusing stars way easier. Boosting the signal in low-light environments is easier to focus on stars without affecting both optical and imaging performance, offering another option to obtain focus over manual focus or the use of a Bahnitov mask. The ergonomics of the LED monitor allow for an articulated screen to flip and swivel at various angles – this is ideal for astrophotography when composing images at more complicated angles to align terrestrial and celestial subject matters.

Built into the camera is a specialized “stacking-based shooting” mode. This feature enables utilisation, alignment and stacking of 12 images in-camera (without need for a star tracker at shorter exposure) to produce a rendered 50mp image output. This process increases Signal-to-Noise-Ratio (SNR) for a cleaner result with noise minimised. A great consideration for Astrophotographers developing their skillset, but also allows photographers to obtain their rushes for more manual control in post.

When taking images just shy of an hour, battery levels of the OM-3's BLX-1 rbattery emained at 95% allowing for good imaging time of a single charge. Over its life span, a single charge is typically rated to last 590 shots per charge whilst operating the LCD monitor. A final consideration is the incorporated USB-C connection port, which allows for an external power bank to be attached and operate for longer durations outdoors.

As an addition, the OI Share app (available for both iOS and Android) offers an option to take images wirelessly operating your smartphone using internal WiFi connection. This setup is ideal for a single shot and can be done for multiple images but requires constant activation of the camera shutter, which is not so ideal when imaging for greater periods of time. A remote shutter release cable therefore is highly advised to take greater control if utilising longer exposures or shooting for prolonged periods of time.

I hope to be able to borrow a OM System OM-3 Astro again in the near future for a longer test in better conditions. But my initial thoughts that this is a great option for getting avid photographers immersed in the world of narrowband imaging, with the sensor modification already applied out of the box. It is a stylish retro-designed mirrorless camera too - and is very well priced compared to other astro cameras. The OM-3 Astro costs around $900 more than the normal OM-3 in the US, and £200 more in the UK.