Nightsky imaging, part1

During christmas, only one night (!) was clear to take some nightsky photos. These three following images were took at place, which is quite a free from light pollution (ie. Vesanto at central Finland). After my eyes had adapted to darkness, the sight was really beautiful. Milky Way was very clearly visible, and no moonlight at all. Dark areas were easily seen.

Natures sounds was really interesting to listen: owl on the near forest, sounds of ice movement on the nearby lake, dogs barking on the neighborhood, water flowing on the small river and low temperature cracking sounds from trees. Interesting experience indeed...

One sound I was not able to recognize - it sounded like mixture of laughing and barking with a hoarse tone in it. I suspect it could be either Eurasian Lynx (Lynx lynx) or Red Fox (Vulpes vulpes). If someone knows this sound, leave a comment...

Orion, Hyades cluster and Pleiades (M45).
Big Dipper at northern sky.
Cygnus and Milky Way.

New type of halo found

At 5th December 2008, couple of web sites informed about new halo type, that was discovered by Marko Riikonen, at northern Finland. It is located below Moilanen arc. See discussion and images about this topic at:

Tähdet ja avaruus -news
Ice crystal halos - blog
Tähdet ja avaruus 8/2008 -magazine
Atmospheric Optics - Les Cowley

Nikon EH-6 secrets, part2

On my previous post #1 about Nikon EH-6, I described alternative supplies for powering DSLR. Since many Nikon models have been released after that, I summarize current situation:

Compatible with EH-6 supply:
D3
D3x

Not compatible with EH-6:
D700 - uses EH-5a/EH-5 supply
D300 - uses EH-5a supply

Sunset colours

On clear and chilly Monday evening I was walking out on company parking place, half an hour after sunset. In the opposite side of sun, earth shadow and belt of Venus were rising above horizon. The sky was strangely colored around sun, in a large area.

Light pink hue was easily visible. Normally during sunset sky turns first to orange and then red, even deep red. I remembered that earlier this year there was a volcanic eruption at Mount Kasatochi, located at Aleutian islands.

I assume this event could cause the colors, but I sill am not 100% sure... During the autumn reports of such colorful sunsets are received from Sweden. Many reports also have been coming from central Europe.

Before this eruption (if I correctly remember) was the famous mount Pinatubo eruption. Huge amount of aerosols and small dust particles were blown into upper atmosphere.

Trip to Kilpisjärvi

During mid-september 2008 I had a nature photography trip to northern Finland, i.e. Kilpisjärvi. In addition to landscape and nature details photographs, I captured some images of atmospheric phenomenon. I am again waiting the next opportunity to get there with my camera, so beautiful the landscape is there when the lightning conditions are good...

Auroras above lake Kilpisjärvi.

Sunpillar above lake Kilpisjärvi.

Misty morning and fogbow.

Swans and nightsky

Yesterday it was a clear sky on the evening already, later on at 11pm I went out to take a photo of Pleiades - M45. My Purpose was to get it composed with part of the public building. I need to try photographing again, since I was now too late. Position of Pleiades was not suitable.

When returning home, I got a really nice "surprise", so to speak... Aircrafts are flying quite a frequently in this area (i.e. Espoo) - so I understood there was another jet flying on the sky. First impression was wrong, oh boy! The "plane" was moving too fast - to be normal one. It was a migrating swan, against the thousands of stars on the nightsky. Below the swan there was a lit public building, a local church (mormonikirkko). Those very powerful and narrow light beams hit the swan from below and made it almost glow magically in the night... The situation was passed away so quickly, but damn it was so beautiful sight! I was happy to return home (although I was a bit suffering from cold weather).

Halo observing

Last few months has been time when only few halos I have been able to notice (per one month). Due to daily work, I cannot observe the skies all-time. Yesterday (9th Oct 2008) I saw few nice common halos at Espoo. 22 ring, 22 upper tangent arc and circumzenithal arc were visible.

I store all my halo observations to Havainto.net -database. If images are available, I'll upload those there also. Halo observing is great fun, just remember to watch at the sky...

Autumn lightning

Late today evening it was nice again to see some natures beautiful lights. At coastal area of southern Finland, there is a rainshower passing by. Some lightning is currently visible behind the clouds. Unfortunately no direct lightning strikes are seen, since the thunderstorm is not very "active". No sounds were heard at my hometown Espoo.

One nice occasion was that, at the same time it started to rain harder, and the "Big Dipper" was visible through the clear cloud area. I will continue to follow situation for a while, at local FLC -lightning radars...

Accessory order ongoing

Another set of dew prevention stuff, plus double crosshair-EP for drift aligning. Waiting for Kendrick 1.25" strip and Antares 10mm to arrive beginnig at next week...

Partial solar eclipse

This time the observation I had to visually only. No possibilities to photograph it due to busy daily work, unfortunately. It still was a beatiful sight. Sky was partially cloudy. I observed it in southerh Finland (Espoo to be precise), around 12:40 local time (GMT +3h). Approximately 40% of the sun disk area was blocked by the moon.

These following pages contains solar images around the world:
Spaceweather.com
NASA solar eclipse page

Televue Everbrite diagonal, part2

I got new replacement mirror for Televue diagonal, I changed it myself. This is how the story goes... First thing is to get proper allen wrench. You need to use 1/16" wrench (a bit larger than 1.5mm wrench). Open all the four screws. Keep the mirror holder block facing down (mirror will not drop). Gently lift up the diagonal body and remove the gasket. Take a note of the gasket position.
Mirror lies now in the holder, scratches are easily seen. And there are lot of those... Remove mirror from the holder. Put it on soft cloth or a piece of lens paper (to avoid any other damage).

On backside of faulty mirror there is a "signature". This most propably refers to quality checking. Either the person performing quality control, did not actually check the mirror, or scratches have been made in the mirror installation phase. TV quality control -> alert, alert...

Based on "signatures", replacement mirror has been checked by two persons...

Mirror holder has two thin strips of soft foam inside, to press the mirror against diagonal body. I am bit worried about this material. How does it work after long time, ten years or more ? Is it still flexible enough to support the mirror ?

Install the replacement mirror on the holder. No scratches seen anymore (few dust particles are present, no affect to actual use).

Take a diagonal body, gasket and mirror holder. Install the gasket in same position as it was when disassembling. Thighten all the four screws.

Final checking of diagonal against bright light, mirror surface looks good.

Televue Everbrite diagonal, part1

After my recent accessory order arrived, Televue 1.25" Everbrite mirror diagonal was a faulty one :-( The mirror inside of was totally full of scratches. After contacting to dealer, it was decided that I receive a new replacement mirror for free, and change it myself.

I still want to believe that TV makes excellent quality products. Within this sample, the quality control checks were not working.

Accessory order ongoing

For preparing my C8 OTA to visual planet observing and other coming challenges, I am about to place order of:

Baader Ortho 9mm eyepiece
TeleVue 1.25" Everbrite diagonal
Kendrick 2006 -heater strip
2" barrel -> T adapter

Blog Admin: Posting comments

Just an announcement... Today I have activated comment filtering, because I'm starting to get comments here that have _nothing_ to do with astronomy hobby (i.e. spam). If you leave a comment, pls be patient to wait a while -> so I can check these comments before accepting them (I get email info when comment is posted). I do not have any intention to modify comment before allowing to publish it, only to check if it is someting related to spam.

Thanks, Timo

Antares 8*50 illuminated RACI finder

My Celestron C8 scope had only a plastic and flimsy red dot finder in original configuration. I needed a better magnifying finder, that will also help to spot dimmer objects on the night sky. There are no detailed measurement reports here, only a personal thoughs and ideas. Hope they will give you some idea about this Antares finder. The configuration looks like following:
Antares finder is attached the SCT frame with Baader finder bracket Rel4 -model. Maximum tube diameter that it can hold, is 72mm. I chose the larger model insteadt of Rel3, because of the larger "dewshield" tube in Antares finder. I was really amazed with the mechanical build and quality of this Baader product (with small cons, see comments). It is very sturdy and can hold bigger finderscopes also, maybe even small guiderscope (I have not tested this yet...). Supplied aluminum block between finder dovetail and finder bracket is removed to get finder more close to SCT.

Antares finder gives correct image in up/down and left/right directions because of 90 degree prism used. The image quality is good for the price, not perfect though. For higher optical quality the price would go very high, so I stay on this level now. Image quality is lower on the edge of field. Currently I did not had possibility to compare this Antares to other finders, so my comments are based on the actual (and short time) use. I've noticed that It takes some time to get familiar with the use of prism finder. I've noticed myself watching between the sky and finder EP, even when the finder is pointed to the right part of the sky :-) When scope position changes, there comes also an issue with finderscope viewing angle. In some directions it is facing sideways. It is possible to rotate finder in Baader bracket (by loosening setscrews a bit). Another method is to loose setscrew on Antares prism and rotate it (requires modification to allen screw). Finder eyepiece has double crosshairs with adjustable illumination (standard 1.25" size)

Antares finder - pros / cons
+ image quality decent/good for the price
+ correct / right angle image
- rear and front caps always dropping
- eyepiece focusing is jamming in low temparatures
- no separate focuser (eyepiece has to be moved)
- loose fit in lens hood tube (need to be attached again)

Baader finder bracket - pros / cons:
+ very good mechanical build and quality
+ feels sturdy
+ disconnected quickly from scope
- finder bracket screws are bit small and slippery
- plastic tips of adjustment screws need to be glued with superglue

Saturn imaging at Nuuksio

After a long time waiting, finally skies cleared. Thanks to my work colleague for the car ride... Expectations were high, but I was disappointed with the results. Seeing was very bad, it caused lot of disturbance in the atmosphere. After stacking I also noticed some "stripes" in the image. Got to find out where they are coming from...

C8 image details:
Location: Nuuksio (Espoo, Finland)
Date: 15th February 2008
Time: 23:43 UTC
Telescope: C8 XLT (2032mm f/10)
Mount: Skywatcher HEQ-5
Barlow: TeleVue 3x
Webcam: Philips SPC900NC
Stacking: Registax v4, 952 frames

It was approximately one year (!) after my last Saturn imaging session (too long time to speak). I made a comparison image pair about Saturn rings. They look more and more narrow each time. Within one or two year, the rings should "disappear", since the plane is pointing towards earth.

Thoughts about weather

What could I say... A lot. But it maybe would not be any "nice language". Raining wet and sleet. Sometimes snow falls on the ground, usually melts in couple of days. But always cloudy, cloudy etc... If correctly remember, during last 3 weeks my C8 hasn't had any night time usage.

While waiting for skies to clear, I am constructing leveling aid for HEQ-5 mount. It consists of aluminum plate and double spirit levels attached to it. You just drop the plate into tripod slot and start fine adjusting the tripod. When I've finished the project, I'll post an article.

Eyepiece carrying case

I am constructing a suitable cases for my planet imaging equipment. I selected a strong molded plastic case from Storm Cases, model iM2100. It had enough space for eyepieces, barlow, webcam and accessories. There is space available for additional eyepieces.

This particular case is also suitable for airline transportion, and can withstand pretty rough handling also. On the long term, I believe it will be good investment instead of many lousy ones. I also need to make similar cases for HEQ-5 mount, C8 OTA and laptop. I am bit worried about the prices of bigger Storm cases now :-) Quality cases indeed...