Astroimager getting focus software#

Focus rangeįigure 1 lists the parameters that I selected for use with my Moonlite focuser. From here there is a choice of using two focusing aids, or a new addition, (more of which shortly). To set up the focusing run, you need to click on ‘Focus Tools’ in the Camera menu. I don’t think has changed much since my review of an earlier edition of The Sky in 2018, so I was able to use the same parameters as before and they worked extremely well. The first, known as is a comprehensive automatic focusing routine that slews to a star of appropriate brightness, places a small sub-frame around the star, computes a suitable exposure time and then finds the critical focus. TSIE features some good tools for attaining sharp focus. Unsurprisingly, the use of a good quality electronic focuser is required to obtain the best results. With my telescope imaging without the focal reducer at f/8, the critical focus zone enlarges to 0.14mm. As the f-ratio increases, the critical focus zone becomes wider. For those that prefer ‘real world’ figures, it equates to 0.0618mm. This is a preposterously small focus zone. Inserting this into the calculation gives 5.32 × 2.2 = 61.8 microns. Using my GSO 254mm Ritchey–Chrétien telescope, equipped with a 0.67× focal reducer, I have an f-ratio of f/5.3 (and a focal length of 1,340mm). The critical focus zone is calculated by multiplying the square of the focal ratio by 2.2, with the result delivered in microns. This is a zone of sharp focus that is smaller in ‘fast’ optical systems with steep light cones, making fast telescopes more difficult to focus.

The point of best focus in an imaging system is known as ‘critical focus’. It’s also essential for any scientific imaging such as photometry. Attaining sharp focus is incredibly difficult and is a make-or-break decider of image quality. This issue, I’d like to assess how well TSIE performs when autoguiding, as well as judging its autofocusing accuracy. With a model containing just 61 stars, I was able to significantly improve the accuracy of my Paramount ME equatorial mount.

Astroimager getting focus software#

The latter allows for the integration of imaging cameras, autoguiders, filter-wheels, focusers and so on to the planetarium software used for controlling equatorial mounts and navigating around the sky.

This new edition of The Sky comes with both TPoint and the Camera Add-on. Last issue we assessed The Sky Imaging Edition’s (TSIE’s) capabilities in creating a precise pointing model for equatorial mounts using its TPoint module. The options at the bottom help to automate and speed up the process of finding a suitable guide star. Here you can choose how many images to take when autofocusing and whether to average multiple exposures together (during poor seeing) and you can determine the Focus Range of an electronic focuser.