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by MattBlissett 2024 days ago
Whilst on holiday in Tonga, I met an amateur astronomer with a decent telescope. I think he said it was "20cm". He was showing anyone interested Jupiter and Saturn, which I remember appearing about outstretched-finger-width.

Later, we somehow attached my camera to the telescope -- it must have just screwed on to the front, as you would attach a filter, since it's not a DSLR with a removable lens. It does have an excessively long zoom (600mm, it's a Sony RX10 Mk IV).

It took some fiddling to get the two devices to work together. We had to realign the telescope by finding stars on the camera's screen, work out where to manually focus the camera, and what settings (noise reduction etc, as well as ISO, aperture, shutter speed and so on) to use.

Combined, we were able to take these photographs of some nebulae[2-3] and a galaxy[4]. I don't remember, but I think the point was that these were not visible just by looking through the telescope.

It's a reasonably expensive camera, but gave noticeably better results than the astronomer's own Canon EOS 760D. If you don't have something similar, try borrowing a friend who likes wildlife / bird / sport photography or similar.

[2] https://matt.blissett.me.uk/photos/2018/2018-09-04-1/13.jpg?...

[3] https://matt.blissett.me.uk/photos/2018/2018-09-04-1/12.jpg?...

[4] https://matt.blissett.me.uk/photos/2018/2018-09-04-1/17.jpg?...

(All are 30s exposures at f4 with ISO 8000. Remove the ?w=2400&h=1800 if you want to see the original size. If someone recognizes the nebulae and galaxies, please let me know what they are -- I lost the notes I took at the time.)

3 comments

Your third upload failed to analyze, so i tried it again[0], this time it succeeded. Nice.

[0] http://nova.astrometry.net/user_images/4205995#annotated

Thanks so much for showing me this service, it's great!
Very nice pictures. I replaced my old DSLR with a mirrorless Canon M50. I did get a T-Ring adapter to fit it to the scope in the future so I will definitely be giving that a go. As you say, some objects can't really be seen with a standard telescope whereas a camera with long exposure can soak in the light. In fact you don't even need a telescope for many of them, a 200mm quality lens will do fine from the pictures I've seen.
Very nice pics! One can also start out without spending much money by using a holder/adapter with a smartphone that has a decent camera. Night mode or astro mode is the minimum to make it useful. I think stacking can be done using video and post-editing if the camera app doesn't allow long exposures.