What are the main advantages of the ASI585MM-AIR's integrated design?
The 3-in-1 design of the ZWO ASI585MM-AIR significantly simplifies your astrophotography setup. It combines the main camera, guide camera, and control computer (ASIAIR) into one unit, which means fewer cables, no need for a separate guidescope or OAG, and no laptop at the telescope. This reduces weight, complexity, and potential sources of error like cable snags or differential flexure.
How does the on-axis guiding on the ASI585MM-AIR work?
The ASI585MM-AIR has a secondary SC2210 guide sensor mounted inside the camera body, just off the axis of the main IMX585 imaging sensor. It picks off stars from the edge of your telescope's corrected image circle. You simply focus your main camera as usual, then use a separate adjustment knob on the camera body to fine-tune the focus of the guide sensor until you find a sharp guide star in the ASIAIR guiding software.
Is the ASI585MM-AIR a good choice for imaging the Horsehead Nebula (Barnard 33) with an 80mm refractor?
Yes, it's an excellent choice. The Horsehead Nebula requires strong performance in the Hydrogen-alpha band, and the ASI585MM-AIR's 91% peak QE makes it highly sensitive to this wavelength. On a typical 80mm f/6 refractor (480mm focal length), the 2.9µm pixels will provide a high-resolution image scale well-suited for capturing the fine details and wisps of gas in that region.
How does the ASI585MM-AIR's 2.9µm pixel size pair with an 8" f/10 SCT for imaging Jupiter?
For planetary imaging, optimal sampling occurs when the focal ratio is 5 to 7 times the pixel size. For the ASI585MM-AIR's 2.9µm pixels, this corresponds to an ideal focal ratio between f/14.5 and f/20.3. An 8" SCT at its native f/10 would be undersampling. To achieve optimal resolution on Jupiter's cloud bands, you should use a 1.5x or 2x Barlow lens to increase the effective focal ratio into that f/15-f/20 range.
Do I need a separate computer at the telescope with the ASI585MM-AIR?
No. The ZWO ASI585MM-AIR has a complete ASIAIR Plus computer built directly into the camera body. You control everything—imaging sequences, guiding, plate solving, and polar alignment—wirelessly from the ASIAIR app on your smartphone or tablet. This eliminates the need for a laptop or other mini-PC at the mount.
What size image circle do I need to use both sensors on the ASI585MM-AIR?
To ensure both the main IMX585 imaging sensor and the offset SC2210 guide sensor are fully illuminated with sharp, undistorted stars, a corrected image circle of at least 36mm is recommended. While the camera may function with a smaller APS-C sized image circle, you may experience vignetting or elongated stars on the guide sensor, which can degrade guiding accuracy.
