Emails – Letters – Tweets – Facebook – Instagram – Kit questions
Email us at inbox@skyatnightmagazine.com
MESSAGE OF THE MONTH
A vintage approach
My solar disc images are fairly mediocre compared to many others I have seen over the years in the magazine, but it’s the method of capture that I thought might be of interest. Having a bit of an obsession with vintage optical tubery, I found myself acquiring a nice old telescope with a little history behind it. This tiny Maksutov-Cassegrain was manufactured by PZO in Poland around 1960. If you went to school in East Germany during the Cold War, this is what you had to study with, and it was supplied from new with 50x and 90x eyepieces. If, however, you were schooled in the West, you had a Zeiss Telementor to play with.
That’s not to say that the PZO T50 optics are second rate, very far from it. This 70mm Maksutov excels at solar disc projection! I used a smartphone to capture the images projected on paper, and then processed them with ‘Snapseed’. You have to get the capture device as perpendicular as possible to the image plate, to avoid distortion and slightly out of focus areas, but it can be done. I am a self-confessed novice when it comes to astrophotography, but I am enjoying the learning journey.
A delightful story, Gary, and nice sharp sunspots in images with a great artistic quality from the paper grain! Compound scopes like Maksutovs aren’t best for solar projection – the folded light path increases heat build-up – but your PZO looks like it’s all metal and without plastic parts that could melt in focused sunlight. – Ed.
This month’s top prize: two Philip’s titles
The ‘Message of the Month’ writer will receive a bundle of two top titles courtesy of astronomy publisher Philip’s: Nigel Henbest’s Stargazing 2022 and Robin Scagell’s Guide to the Northern Constellations
Winner’s details will be passed on to Octopus Publishing to fulfil the prize
Puzzling solution
The grid-like pattern on Paul Mitchell’s photograph of the Moon (‘Interactive’, October 2021 issue, ‘Lunar puzzle’, page 21; see above) is likely to be a picture of the camera’s CCD, caused by the light entering the camera due to what’s known as ‘total internal reflection’. This is defined as the optical phenomenon in which waves arriving at the interface from one medium to another are not refracted into the second medium, but completely reflected back into the first medium.
Seeing double
As a newbie to astrophotography, I was pleased to get a picture of the Jupiter double moon shadow transit on 4 October that was highlighted in the October issue (‘Sky Guide’). At around 8:40pm the clouds parted and I shot two 1,000 frame AVI videos with my Celestron NexStar Evolution 9.25 telescope and Skyris 236C colour CCD camera with an ultraviolet/ infrared filter.
During the second of these transits, the clouds closed in and the view was lost. But I could see in the thumbnails on my laptop that there were two black specks, telling me that I’d captured the moon shadows.The final pictures were processed with iCap 2.4, AutoStakkert!, RegiStax and Affinity Photo; they may not be of the standard of your always excellent contributors, but they are pleasing to me nonetheless.
Enjoy the view
Thanks to Kevin Thompson from Knighton, Powys, for sending in his design for the TOMO Astro Chair Mk1 (above). In terms of usefulness and comfort, it’s a winner, Kevin! Ergonomically designed in the best tradition of Heath Robinson and Rowland Emett, it assures a pain-free view of the stars, with everything that might be needed in a position to eliminate the need for a reclined observer to lift their gaze from the eyepiece. We hope a Mk2 is forthcoming, and might include ingeniously powered motor drives for the altitude and azimuth actuator wheels, which move telescope and observer as one. – Ed.
Morning Moon
I used the early pandemic days to try my hand at astrophotography, purchasing a half-decent DSLR and a Samyang 135mm lens. I set about viewing a multitude of YouTube videos on how to take untracked images of deep-sky objects, then stack and post-process them.
A year later I’ve added some kit, including a star tracker, but I’ve also noticed a distinct lack of clear-sky opportunities this year compared with last! However, while brushing my teeth on the morning of 5 October, I was confronted with a fantastic view of the Moon through a Velux window. I grabbed my smartphone in the hope of capturing a half decent image. Two shots later – plus some minor tweaks in Photoshop Express on my phone – and the result (above) didn’t seem half bad.
Society In Focus
Letchworth and District Astronomical Society (LDAS) has been ‘looking up’ from Hertfordshire for over 35 years. Founded in 1985 in Stevenage, we took our new name in 1991 when Letchworth, the first Garden City, offered us a site for our observatory at Standalone Farm.
We are a family-based society where everyone is invited to join in our activities. Our main meeting occurs on the last Wednesday of the month, when we normally have a guest speaker, a chat and a roundup of news and objects of interest to observe in the coming month. Recent speakers have talked about dark skies, binocular astronomy, NASA’s Dawn mission and giant elliptical galaxies, delivered in our annual lecture by new honorary president Dr Matt Boswell of the Cambridge Institute of Astronomy.
During lockdown we missed our star parties and workshops, but we managed to run two telescope workshops online and also got in some live online solar observing from a member’s observatory. In August 2021 we held a picnic, and a clear sky in September allowed us to enjoy an informal pop-up planetary observing evening. The re-silvered mirror of one of our hire scopes saw first light and gave us excellent views.
Looking ahead, we have a project underway to improve access to our observatory and also to improve the view to the southwest sky by pruning the hedge that has grown while we have been away. Mike Eltringham, Committee member, LDAS
Tweet
Mehmet Karagül @mehmetkaraguel • 24 Oct
Including a deer in this photo of a Hunter’s Moon on 20 October 2021 would be perfect, but all I have is a dry tree branch that looks a bit like deer antlers. #HuntersMoon #FullMoon
On Facebook
WE ASKED: Real or imaginary, what do you want for Christmas this year?
David Mottershead A cloud zapper!
Joe Padfield A chainsaw to cut the neighbours’ trees down so I can see the southern horizon!
Peter Turvey A 6-inch Cooke refractor.
Anne-Marie Hinks Benstead A year of clear skies!
Steve Green Why wait? Get it now! An observatory at the bottom of the garden.
Henry Shaw I would like my whole telescope shopping list, but that’s a very big list.
Gerry Lecount A good quality high-magnitude spotting scope.
Jonathan Brown Meteor samples.
Carol Miller An eVscope. I have ongoing eye problems, one of which is beginning to curtail my viewing through a regular telescope, so seeing the Unistellar eVscope eQuinox featured in Sky At Night Magazine (‘First Light’, September issue, page 86) brought hope to a future of continued sky-watching. I hope to have one in 2023 when I reach my 60th birthday!
cellistontheroof • 20 October
A quick capture of Jupiter from Sunday evening, while I was prepping for trying to capture Uranus. I assembled the imaging train and noticed that the Great Red Spot was just about to leave our sight, so I took a quick two-minute exposure. Seeing was poor but c’est l’astronomie down here! Always happy to see the cluster of white storms in the southern hemisphere! @bbcskyatnightmag @ astronomypicturesdaily @astronomy. magazine @astronomyinsider
Scope Doctor
Our equipment specialist, Steve Richards, cures your optical ailments and technical maladies
Email your queries to scopedoctor@skyatnightmagazine.com
I have a Sky-Watcher 200P Dobsonian telescope that appears to have mildew or mould on the primary mirror. Is this a big problem and should I clean the mirror? SAMUEL PARRY
Cleaning a Newtonian reflector’s mirror should only be carried out if it is absolutely necessary. However, mildew and mould can damage the surface through chemical reactions so if you suspect their presence, cleaning the mirror correctly would be a good idea. This should never be done with a cloth but with the gentle action of water.
Start by carefully removing the mirror from its mounting cell and place it in a plastic bowl full of tepid water and two drops of mild detergent. Leave to soak for five minutes and rinse under tepid running water. Refill the bowl with fresh tepid water and another two drops of detergent then soak a piece of cotton wool in the water and drag it, under its own weight only, across the mirror once and discard. Repeat with several more pieces of cotton wool until the whole surface has been cleaned. Pour distilled water over the mirror and place it on its side on a towel until it is dry then re-install and collimate.
Steve’s top tip
What is a finderscope?
Finding celestial objects through a telescope eyepiece can be harder than you might imagine as the small field of view and magnification of the instrument makes it easy to miss a target. A finderscope is a small telescope that attaches to the main observing telescope and is aligned with it. A finderscope’s short focal length typically gives a wide field of view, perfect for star-hopping to the object you seek by observing through it to get you most of the way there. Final pointing is then carried out using a long focal length eyepiece in the observing scope, locating the object ready for observing.
Steve Richards is a keen astro imager and an astronomy equipment expert