Friday, 25 September 2015

Total Lunar Eclipse - camera selection briefing

Small telescope (1300mm)

So you want to take a picture of the lunar eclipse? One question any expert will ask is what type of camera you have available for the event. Another is just what you want to photograph.

To produce a nice close up of the eclipsed Moon, you will want a small telescope or telephoto lens. The Moon appears to be about half a degree in size (yes, even during a so called Super Moon it appears that large). Using that information, the next step is to determine the field of view of your lens system and camera, which is a bit technical. This can be done with a formula (explained at https://www.eclipse-chasers.com/photo/Photo4.shtml) involving the size of your camera image plane (chip size) and the effective focal length. Cutting to the chase, I recommend a lens with a focal length of 200mm and more to show the Moon best.

April 2015 Lunar eclipse - EFL of 100mm
A frequently asked question is whether or not a camera phone can be used. The answer is an emphatic yes, just don't expect the greatest detail of the Moon and you will want to try several times before you get a nice image. The small lens will not capture much detail of the Moon however you can get great images of people and the eclipse. Just don't use the flash without warning others first!

When using a telescope or long telephoto lens you will need to manually set the exposure. Eclipses confuse automatic camera settings. As the eclipse darkens, longer and longer exposures will be needed to reveal details as seen in the image below. Both images of the eclipse were taken at roughly the same time, just different exposure settings. Note that the longer exposure washed out the illuminated surface while bringing out the eclipsed side where the shorter exposure shows the lit surface and a completely blacked out eclipse area.


A very nice to have is a tripod or fixed base for a longer exposure. Hand held images will show some blurring since it is nearly impossible to hold the camera perfectly still that long. Bracing yourself agains a building or wall might work if you are lucky but I strongly recommend a tripod or set it on the ground facing the right way and hope for the best.

Another trick is to use the delay feature (if available) on your camera. Point the camera at the eclipse and start the exposure. After a brief count down, the camera will take the image. The delay allows vibrations to settle and will result in sharper looking images. Using this method you can take an image that includes both yourself and the eclipse!

So the bottom line? If you want to try taking an image of the lunar eclipse, a nice big camera and lens on a tripod is best. But don't let that dissuade you from trying! I have seen plenty of great images taken with small camera phones. You just need to take a lot of images and have a lot of luck!


Saturday, 19 September 2015

Bug Fix 1988 Eclipses

There was a file mix up in the Mar and Sep 1988 eclipses. I think I have sorted it out, but if you are one of the few that saw either, please double check your log and let me know if there are any problems.

I am not sure how the old file snuck back in, but it can happen. We had to restore from back ups a few times after attacks on the server and issues with a power supply. So I am going to presume that is when it re-appeared.

Update 22-Sep-15 - found anomalies with ASE 2013 thanks to Joe Cali. Those have been corrected. Please check your log to make sure it is correct and let me know if not!

Sorry for any confusion.

Friday, 18 September 2015

Added partial eclipse 13-Sep-15 to list

If you saw the partial solar eclipse of 13 September 2015 you can add it to your log entries. I know a couple people traveled to South Africa to catch a view and had partial clouded success. The IAU WGSE (International Astronomical Union, Working Group on Solar Eclipses) had a team there and here is a summary of the observations.

This situation makes me ponder the general rule of thumb: Anywhere for a total solar eclipse, Reasonable travel for an annular, and set up near home for partials. Observers from Germany, France, and the USA went to the southern most tip of Africa to see this last partial solar eclipse (just over 40% obscuration). They could have seen more (over 70% obscuration) if they went to Antarctica.

I realize that a portion of the visit to Africa was to help educate others for upcoming annular and total solar eclipses but it still makes me wonder why one would want to travel that far for a partial eclipse. The best answer thus far is "because we can". I say congratulations to all that went and saw the eclipse!

As a side note, Xavier Jubier and Mike Kentrianakis had just completed a grueling drive from Oregon to Missouri and back checking out eclipse sites before boarding a flight to Cape Town. Now that's eclipse chasing!

Partial Eclipse Clouds
When dealing with any eclipse one wants perfect weather. Unlike a total solar eclipse, a partial eclipse can be observed if just glimpses of the Sun can be seen between clouds. It can be frustrating to photograph the eclipse under such circumstances. Just as you get the focus perfect, another cloud gets in the way. Or you just can't seem to get a perfect focus because of the atmosphere. One thing you should not do is remove the solar filter unless you know exactly what you are doing (i.e.: EXPERT level). A sudden clear hole could damage equipment and worse, blind you. It is advised to always keep the solar filter on when the camera system is pointed towards the Sun.




Tuesday, 8 September 2015

TSE 2016 and the International Dateline

The Total Solar Eclipse in March 2016 crosses the International Dateline. For some, this can be a cause of confusion because the eclipse will seem to time travel.

Here is the deal, the eclipse starts on the 9th of March, in the morning, near Indonesia. The path of the eclipse then moves to the EAST and north. As the path moves along towards the East it will encounter the International Dateline. Suddenly the date changes to the 8th of March. The eclipse moved back a day! The eclipse continues through to the EAST and north ending at sunset on the 8th of March.

NUMEROUS WEB PAGES HAVE THIS ALL WRONG! I want to make sure everyone is setting up on the right day for this eclipse.

So here, in simplified cartoon format....

What day should you set up?


Okay, this is confusing!
Can you see the eclipse east of the International Dateline? If you are on an airplane or a ship, yes, it is all ocean.


Monday, 7 September 2015

Eclipse photo drones - really?

Tricky landing a drone on a ship
Just a few days ago an interesting question came up amongst eclipse enthusiasts. "Any one planning to use a drone to photograph the eclipse event?"
Leave the drones to the pros
The question about drone usage led to a variety of responses such as "Why do that?" and "I don't want drones flying over head as the eclipse takes place!".

There are plenty of good reasons not to try to fly a drone during totality:

Drones and Eclipses do not mix!
1) You will want to watch the eclipse, not the drone.
2) Might block view of others.
3) Could crash and cause major problems.
4) Drone based cameras are looking at the ground, not the eclipse.

The best use of a drone during a solar eclipse is to capture an image of the crowd before and/or after totality. During totality, keep it on the ground!

If you are a pro drone driver then you should know all the safety rules and considerations. Keep the drone away from large crowds (photograph from a distance), don't try a fly over during totality, be respectful of others, and double or triple check your equipment before use.

In preparation for the 2016 TSE, Paul D Maley and RING OF FIRE EXPEDITIONS have been preparing to try a drone launch from a ship near Guam. He has been working on this plan for over a year and has put together a solution that should work - provided the weather is cooperative. We are all looking forward to the results he gets!
During the excitement of totality the wrong button was pushed





Saturday, 5 September 2015

20cm (8") Telescope

For the past six years I have been using my trusty old Quester 3.5" telescope here in Jamaica. It is a great scope,  extremely portable, but really not well suited to prolong exposure in the tropics. The mirror surface has begun to show wear, the finder lost all silvering (thanks to an enthusiastic assistant who was trying to clean it up), and the tracking motors need cleaned. So I moved it back to the States and will be sending it off to Quester for refurb before the 2017 eclipse.

Dark sky when the lights out!
This has left me without a telescope for the interim. After extensive thought and study I have decided to import an Orion 20cm (8") f/5.9 telescope. This scope will work great for public presentations and my own enjoyment as it is portable (about 20 kg, 50#) and should fit in the back of my car.

The sky in Jamaica is very dark, even more so when a power outage is underway. And we live on the coast meaning that I have extremely dark sky to the sea. The wide field (f5.9 with 2" eyepiece) viewing should be sensational!

The scope is on the dock in Miami. Soon it will be on a ship, then in customs, and in a few weeks (before the lunar eclipse) I hope to be reporting on the views. I am looking forward to it!

Friday, 4 September 2015

Lunar Eclipse September 2015 - Perigee Super Lunar Eclipse

The Total Lunar Eclipse (TLE) that will take place on the 27th of September (2015) just so happens to occur near perigee. That doesn't sound too exciting does it? How about The next TLE is a SUPER TLE! Sensational, just like the press is likely to pick up.
Super Lunar Eclipse!

So what's up with that?

The Moon's orbit about the Earth is not a perfect circle. It is an ellipse with the Earth at one of the foci points. And this ellipse is kind of wobbling so some cool mathematics are needed to keep track of these things. Here is a great web page discussing the concepts by John Walker.

So what makes up a super moon? That is simply when the Moon is full and at the point in its orbit closest to the Earth, perigee. Super moon just sounds better.

Okay, so how close to super is this eclipse coming up? Pretty close. According to world renowned calculator Jean Meeus (of Belgium) the differences are:

Moon in perigee at 01:46 UT,
mid-totality at    02:47 UT.

Within the hour! That is pretty close. And the question has been raised, just how rare is this level of Super Lunar Eclipse (SLE)?!

Darren Beard has determined that the next TLEs coming up with perigee within 15 hours of the event are not too rare,  27 Jul 2018, 21 Jan 2019. But that is within 15 hours. What about near an hour or less like this one?

Can you really tell the difference? Not unless you regularly photograph the Moon with a lens that produces an image of the Moon that fills the frame.

So cool, it is a Super Lunar Eclipse (SLE). Now let us see what the press makes of that!

Thursday, 3 September 2015

Lunar Eclipse 2015 Photography

Hey, you want to photograph the Total Lunar Eclipse (TLE) on 27 September 2015? Why not? It is easy and the results can be really great.

Lunar Eclipse
If you have a telescope or long lens, the job is not that complicated. Here is a web site that details Lunar Eclipse photography I wrote some time ago. It is still apropos.

But what if you don't want to use a telescope or telephoto lens? At the very least you will want a tripod or some way to mount the camera steady. Lunar eclipse pictures require a longer exposure and it is too easy to shake or move while the image is being captured. So figure out a way to mount or hold the camera steady. A simple table tripod is all that is needed in most cases.

Tripod and digital camera from parking lot 110mm EFL
The exposure time will vary depending on your lens configuration but expect it to be between half a second and several seconds. You can capture stars in your image with exposures lasting several seconds. This leads to your camera, it needs to be taken out of fully automatic mode (if possible) and set to manual. Same with the focus mechanism if that is an option. Set the focus to infinity and use an initial exposure of two-seconds to see what you get. If your camera has a delay shutter mode, use it. It will steady on the mount for a few seconds and then take the image.

With a camera phone your options are more limited. Modern camera phones can do night time photography, some do it automatically, some try to turn to on the light. Don't put on the light. That is a waste and a bother to everyone else around you. The exception may be to get an image of people looking at the eclipse but even then there may be enough light around to use.
Sunrise Lunar Eclipse from beach in Jamaica


Wednesday, 2 September 2015

Lunar Eclipse 27 Sept 2015

Total Lunar Eclipse
There will be a total lunar eclipse (TLE) visible in the western hemisphere in the evening of Sunday, the 27th of September. This eclipse takes place early enough for many to be able to see it and still get a good nights sleep before Monday rolls around. A lot of details about the eclipse and visibility can be found on Fred Espenak's most excellent website here: http://eclipsewise.com/lunar/LEnews/TLE2015Sep28/TLE2015Sep28.html

Lunar eclipses are not as exciting as Solar eclipses. Many call it the blood moon and other fancy names meant to make it seem amazing. Most will not notice it unless it is called out because modern people living amongst light polluted nights don't (can't) really notice much up in the sky. So if you have a telescope, set it up and invite others to take a look.

During totality the sky is much darker. The bright Moon has been dimmed so that the stars are easy to easy. Hanging out near the brown-red Moon is the planet Uranus at magnitude 6. Uranus is about five degrees (RA) east of the eclipsed Moon. While not visible to the eye it can be found using binoculars or a small telescope as a blue-green star like object. If you have an equatorial telescope mount, first point it at the Moon using a low magnification eyepiece. Then nudge the view along the RA axis to the East slowly looking for a blue-green star.

Moon and Uranus in Pisces


Finding Uranus in Pisces


Tuesday, 1 September 2015

2017 - Another road trip report soon come

Eclipse chasers are taking advantage of the open road for the upcoming Great American Eclipse. As I write this Michael Kentrianakis (recently appointed as eclipse project manager by the AAS) and Xavier Jubier (the eclipse maestro) of France are driving across the American western states checking out eclipse viewing sites and educating people along the way. A report of their journey will be appearing in a future Astronomy magazine blog or article. They are driving from Oregon to St Louis and back again. Keep an eye out for them if you are along the path!

If you see this bumper magnet, the vehicle contains eclipse chasers!
Rarely do we get the advantage to thoroughly explore such an immense territory before an eclipse. But because this eclipse traverses the continental USA (from Oregon to South Carolina) there are an abundance of possibilities. And to make things even better, there is a lot of weather data available from airports and towns in and near the path. For those of us that really enjoy studying the climate and options for observation, this eclipse has been the best thus far.

IS there a best place to be? Yes, where ever you can see the eclipse in totality!