Dobsonian Astrophotography

So what about the other 1%?

I said I was a 99% visual observer who prefer “live” views, but once in a while to use a smartphone to capture an image.

The Dobsonian mount is very limiting and imaging with a smartphone is fiddly and with no stacking or processing (I have better things to do with my time), the images are not going to impress anyone but are good enough for me.
It is worth bearing in mind that the view through the eyepiece is always better than these images. For example, globular clusters like M13 have an almost 3D quality about them. That’s the advantage of a live view.

Venus, Jupiter, Saturn
Double Cluster in Perseus NGC 869 (above)and NGC 884 (below) / Orion Nebula M42
Sunspots / The moon

The phone holder is a Celestron NexYZ. A light is shone down the aperture and the bright light used to align the three adjusters (left/right, up/down, in/out) so that it is looking through the centre of the eyepiece.

It fits onto the edge of the eyepiece (in my case a rather wide Baader Zoom or a 2″ wide-angle) and using three adjusting bolts (up/down, left/right and in/out) allows you to centre the camera directly above the eyepiece.  The weight of my phone (a OnePlus 8 Pro) does cause a sag but a pad between the phone holder alleviates this.

The camera is used in PRO mode with focus set to infinity. ISO adjusted according to the brightness of the target. A 3 second shutter delay reduced shake.

 

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