The Altair Astro self-centering smartphone adaptor is a solidly-built metal, plastic and rubber product that performs well and is pretty easy to set up and use.
Although smartphones may never replace dedicated planetary or deep-sky cameras for specialist astro imaging work, modern smartphones can take pleasing images of brighter objects such as the Sun (via a suitable solar filter), Moon or brighter planets by simply holding the phone’s camera up to the eyepiece and clicking away until you get lucky.
One of the early frustrations when using a phone at the eyepiece was getting the exposure and focus right, but with increasingly sophisticated smartphones and apps to drive them, this is less of an issue: that is, as long as you can hold the phone steady enough at the right location whilst you adjust those settings.
The Altair Astro self-centering smartphone adaptor comes in very handy to help with this task, holding the phone the correct distance from the eyepiece and the right lateral position whilst you tweak the exposure and the focus to get the preview image looking good. It then holds the phone steady enough to eliminate any movement smearing the image during the exposure.
To operate, you adjust four rubber-coated clamping arms to hold the phone’s camera lens centrally over the circular hole in the adaptor and lock the arms securely.
You then use a clever three-finger gripper system which tightens evenly onto your 1.25-inch eyepiece body and keeps everything central.
Altair recommend folding down the eyecup before fitting the adaptor, but depending on the eyepiece you have you may need to reposition the adaptor a bit further back from the closest position so that the phone lens sits at the right eye relief position to maximise the field of view.
And that’s it: you are now able to take your time on that perfect composition!