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My travels in Sweden:
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Page:MAK, Mariestad Astronomy Club have arranged a Star party in September 2018. I decided to visit that, it's the third time for me. It was held from 7 to 9 September, 2018. I was in a bit hurry and could only stay on the Saturday. It's 320 km away from where I live in Stockholm and it don't take very much hours to drive. But for me that go by the small roads it take much longer time. I started early in the morning 5 am and arrived 5 hours later. Why go by small roads? Because I want to see exiting things, that's what I'm living for! Bifrost ObservatoryBifrost observatory is suited about a 10 km south-west of Mariestad. 
When you arrive to the MAK club you get this view in front of you, an observatory building that holds two big telescopes and many smaller ones. The telescope to the right has just got a new aluminum surface coat and people installed the mirror in the telescope frame yesterday. 
From the observatory balcony you get this view over the place. The tent where the second hand market is and the parking lot behind. In front of the cars toward us are where the visitors set up their telescopes. 
The dome that cover one of the telescopes. 
One of the more important things to do at a meeting like this is to talk to all people. Normally you only have contact with them over the internet. Now it's time to see them in real life. The morning was very rainy, but at none the Sun shine came to us. 
Other things to do is to look at the impressive telescopes that people had brought with them. This is a huge twin Dobson, it has double 15.4" f/4.4 mirrors. Why twin? Because you want to use both of your eyes. If you get the opportunity to look through a telescope like this, don't miss that! The owner is Sten-Arne and he have thoughts about to sell it, if you are interested, contact me and I give your contact information to Sten-Arne. Contact information
It is very complicated to adjust the optics to fit different peoples eyes, it must align very precise to the distance between your eyes. 
Jan-Olov has brought with him two big mirrors, Joel explained to me that maybe the left mirror was the tool to grind the other with. Maybe he want to sell them. It looks to be a hand made grind mirror project. Never done that myself, you have to spent many months of hard work and do it with extremely high precision, we talk nanometers! 
Looks to be a bargain, just 100 Euros, must be something that I could use it for. When I was walking around and thinking about it someone else bought it! |
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I had to compensate that I missed that bargain, instead I found this mini mount head with fine adjustment knobs. I'm not sure what I shall use it for, maybe when I'm doing macro photographing. 
More used equipment that are for sell. The orange tube is a six inch Celestron telescope of Schmidt Cassegrain construction, that makes a big telescope in a very compact format. 
On this table you find electronic devices and instruments. 
About two o'clock pm there was time to listen to who won the Margareta Westerberg prize this year. Margareta was a very active amateur astronomer, not so common with female amateur astronomer in earlier days. 
And the winner was Timo Karhula, Johan Warell hands over the prize. Timo got this prize because of his very carefully notations and documentation when doing visually observations. If I remember correct Timo is used to travel all the way down to Australia and do his observations with a big Dobson. That's a distance of more then 15,000 km, to our summer house we have 40 km and even that sometimes feels like a long way to drive. After this we got a speech from Torbjörn Holmqvisst about a vacation at the isle of Tenerife with observation places. 
Next speech was done by Johan Warell, he showed us how to find the brightness of comets with digital cameras. The weak tail of a comet isn't so easy to find the brightness of visually, with computer aid it's much easier and more precise. After this there was a break. 
I walk out to the telescope place to see if there was any new arrivers. Here I have found Anders Wettergren testing his big Dobson telescope, a 18" mirror. He tests if the fabric is dark enough, you don't want any stray light into the light path, it will reduce the contrast. It's fantastic that you can have a big instrument like this and still have it transportable. 
This is Joel von Knorring, he is very famous in Sweden and maybe the whole world. He has grinded telescope mirrors whole his life, hundreds of them and the biggest one had a diameter of 76 cm or 30". He has also learned a lot of people how to do it. Amateur astronomy at its best. Joel say: "I have grinded these pair of 15.4" f/4.4 mirrors". |
Did they succeed in selling microscopes at a star meeting? At least people looks to be very interesting. 
Now it's time for the second part. It's professor Hans Olofsson from Chalmers who holds the speech. 
He tell us about Stellar mergers, and specially about the object HD101504. They suspect that many planetary nebulas can have its origin from a star and a planetary gas giant system. Very interesting to listing to him. After this we got to learn about a constellation by Anders Wettergren, you know him, the man with the big 18" Dobson telescope you saw earlier. 
I took a walk up to the workshop in the big observatory. They have a lot of big machines here, they are old but very useful if you have some special parts to make. At least I think members of MAK can be allowed to use this machines. Write and ask them if you have any need of special parts, you have the contact information at the bottom of this page. 
I was walking around in the observatory building and looked at the old telescopes that have been made by amateur astronomers in earlier times. Here is a Newton telescope with an equatorial mount built of wood. It looks to be a 8" mirror, 8" mirror was very big in earlier times, just a dream for most people. I like those nice looking wooden telescopes from earlier times. Sören told me that this telescope was built in the beginning of 2000s as project in the club together with others. Maybe someone can tell us who built this telescope and when?
Update: 
Another mirror telescope, the sign say 4000 m focal length! And note the strange angle of the focuser. Built by Sven O Rehnlund.
Update: On the sign on the tube you can read "Facit me", it is not any technical term, it's Latin Martin told me. My girlfriend who understands Latin helped me and told it is "Who made me" translated to English. Martin and I discussed how the telescope could have 4000 mm focal length in a small 2000 mm tube. We don't think Sven used a Barlow lens to achieved this, maybe it's a folded construction. Or maybe it's even more advanced with an off axis ray and then no obstacle in the ray path, that's maybe why the focuser are mounted in a tilted angle. I have to look inside this tube next time I visit MAK. Sven did also advanced grinding of lenses. 
What is the gears purpose, maybe fine adjusting of the focus? Sören helped me with some details: When this telescope is focused the whole secondary mirror moves. He thinks the telescope has a 10" mirror and maybe built in the late 1990s.
Update: The telescope could be setup in two modes. One mode for visual observations with a small secondary mirror. The second mode a photographic mode with a big secondary mirror to get a wide field with low vignetting. He was commonly photographing with camera lenses, Schmidt telescope and Newton telescope. He had great success in observations of variables, to it's help he also built a mechanical optical blink comparator. If you don't know what a blink comparator is, have a look here at Wikipedia: Martin has provided three links with information about the above amateur astronomers Dahlmark and Fogelquist. They are only in Swedish but you can use Google translator or similar to have them in your own language:
Break and talk time before the dinner. Now the evening darkness start and we could see that the clouds go away, will there be a clear sky tonight? |
Sören Persson, the director of the MAK club invite us to the dinner with a speech about the MAK club in old times. 
This is something you don't want to miss, an evening buffet with salmon or roast beef and a desert, very tasty! 
During the dinner there are a lot of talks, do you have any idea what we are talking about? After the dinner I have to take the car and drive to next stop for me. This day and evening have been grate, my third visit at the MAK club. Maybe you live close to Mariestad and want to join the MAK, Mariestad Astronomy Club?
Memories of my visit to MAK 2018.
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