Last minute tips for solar eclipse 20.3.2015

So, tomorrow, where weather permits, a solar eclipse will be visible in Europe, Northern Africa and in parts of Middle East, Central Asia and Western Siberia. The line of totality of this eclipse will be in Northern Atlantic Ocean. Only land areas, where a total eclipse can be seen are Faroe islands and Svalbard islands in the Arctic ocean. Everywhere else, the eclipse will be a partial eclipse. The maximum lenght of totality in this eclipse is 2m and 46s. The duration of the whole eclipse is roughly two hours. There’s plenty of information about the eclipse for example at site called solareclipse2015.org.uk.

Visibility map of solar eclipse March 20th 2015.
Visibility map of solar eclipse March 20th 2015.

How to observe the eclipse safely?

When observing Sun and the eclipse, you should do it safely and with safe methods! Do not ever attempt to look straight towards the Sun with naked eye or with telescope, not even if the eclipse is very deep at your location! Only during the couple minutes of totality it is safe to have a look at the eclipsed Sun with naked eye.

There are two safe methods for observing the eclipse: 1) observing with solar filter, 2) projecting method. Ideally, you should have a proper solar filter made specifically for solar observing. It can be a filter made of AstroSolar -film or it can be a filter made of special glass. AstroSolar -film is a cheap but safe alternative, and you can easily get started with filter of that kind. Four years ago I wrote a blogpost about how to easily make a solar filter for you of AstroSolar -film. With the method presented in that article, it is easy to make a simple solar filter for your telescope, binoculars or a camera lens. It is also possible to watch the eclipse with naked eye through the AstroSolar -film. At the homepage of sky and Telescope, there is a good article about how to safely observe the Sun, and how to observe the sun with projecting method. If you don’t have AstroSolar or any other proper solar filter available, you can use a welder’s glass for watching the solar eclipse. The welder’s glass should be properly dark for safe solar viewing. You can ask for welder’s glass at your local hardware store.

How to photograph the eclipse?

Now I’m going to give you couple of hints about how to photograph the solar eclipse. These tips are specifically for the ones who have an opportunity to photograph the eclipse through a telescope. First of all, you need a DSLR camera and an adaptor ring for your camera. You also should have a adaptor sleeve in your telescope with proper threads for the adaptor ring. You just simply remove the lens from the camera, and set the adaptor ring to the camera the same way you set a lens to the camera. Then just make sure, that the solar filter is in it’s place at the objective side of your telescope.

When the camera is attached to the telescope, aim the telescope roughly to Sun. Do not look through the finder for locating the Sun! Instead, use the image of the Sun for locating the Sun in field your telescope. For example, place a white piece of paper behind the finderscope so that you can see the shadow of the finderscope at the paper. If you can also see the projected image of the Sun at the paper, then just turn the telescope (around rectascension and/or declination axises) so that the image of the Sun s exactly at the shadow of the finderscope. Then the Sun should be in the field (assuming that your finderscope is in alignment with the telescope). Then use the ‘live view’ mode of your camera to make sure that the Sun is in the middle of the view and to make sure that it is focused. Focus normally with the focusing wheel of your telescope. In live view mode, you can zoom in to some sunspots or at the limb of the Sun to make sure, that the image is as well focused as possible.

When taking photos, use short exposure times. The exposure time can be as short as 1/800s – 1/3200s. Ideally, you should take some test shots before the eclipse for finding the best settings for your setup. Also during the eclipse, you can take series of photos with different settings and then choose the best shots afterwards. ISO value can be something like 100 to 400. As the white balace setting, you can use for example daylight or automate mode. And remember to use the manual (M) program for solar photography!

If you don’t have an DSLR camera, you can take photos through the ocular of your telescope with your compact camera or a camera of your smartphone. This method is simply known as digiscoping.

The partial eclipse of June 2nd 2011 observed and photographed by me in Utsjoki, Finland with digispocing -method.
The partial eclipse of June 2nd 2011 observed and photographed by me in Utsjoki, Finland with digispocing -method.

Briefly:

  • Exposure time: 1/800s to 1/3200s
  • ISO: 100 to 400
  • White balance: automate or daylight mode

Okay, so with these tips you should have better chances at succesfully observing and photographing the solar eclipse on 20th March 2015! I wish you the best of luck with observing this rare, natural phenomena!

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How to find Nova Del 2013

The nova of Delphinus 2013 is still shining in the southern sky, and it’s brightness right now is about 5,0 magnitudes. It’s brightness peaked around 15./16. of August. The maximum brightness then was about 4,2 magnitudes. At maximum brightness, it would have easily been visible with naked eye even in some light polluted sub-urban areas! Now the nova have been getting fainter, but the decrease of brightness has been quite slow. It means that it is still a suitable target for observers with small binoculars or telescope! This nova is one of the 20 brightest novas all time, so this is a must-see object for every amateur astronomer and stargazer!

Then how to find the nova from the sky?

Look at the southern sky, there you will find constellation of Aquila, the eagle. The brightest star of Aquila, Altair, is the southernmost star of the so-called Summer Triangle. The stars of Summer Triangle are Altair (Aquila), Deneb (Cygnus, the swan) and Vega (Lyra, the lyre). Now go about 10º from Altair to northeast. From there, you will find small constellations of Delphinus, the dolphin and Sagitta. Sagitta is latin for “arrow”, and actually the small but distinct arrow -asterism of Sagitta is pointing directly to the nova! The nova is located roughly halfway from the easternmost star of Sagitta (eta Sge) towards star 28 Vul in constellation of Vulpecula, the fox.

Other way is to start from Alpha Del. From Alpha Del, go 5º north to 28 Vul. From 28 Vul, go 3º west, and there you can find the nova! The nova is part of a triangular asterism, which is pointing westwards to constellation of Sagitta. The nova itself is the westernmost star of this asterism!