Astronomy how to Photograph Lunar Eclipses

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Viewing lunar eclipses can only be described as a sensational experience. Such a pleasure it is to set eyes on what looks somewhat like a ripe peach sitting within the sky. To say lunar eclipses are wonderful to photograph is an understatement indeed. Aligning your camera on a lunar eclipse is second to none. Having captured the moon’s progress through the earth’s shadow back in July of 2000, the author knows only too well how much enjoyment one can get from photographing lunar eclipses. Such a wondrous spectacle this was and you too can partake of the fun and excitement of photographing a lunar eclipse if you read on to learn how.

A lunar eclipse occurs when the moon sits between the sun and the moon in a manner which has the earth’s shadow darkening the moon. They basically sit in a straight line. The moon orbits the earth every 27.3 days (this is called the sidereal period). A lunar eclipse can only occur when the moon is full. Scientists call the dark, central shadow the umbra. The lighter shadow which surrounds this is called the penumbra. The penumbra shadow is not easy to detect due to its shadow being relatively weak. Those watching a lunar eclipse will note that the excitement begins when the umbra touches the lunar surface for the first time,

When the moon is completely immersed in the earth’s umbral shadow, what is deemed ‘totality’ occurs. The stunning orange-red hues come from sunlight which is filtered and bent by the earth’s atmosphere around its own shadow. The beautifully coloured eclipses take place when earth’s upper atmosphere is more transparent than any other time. Darker lunar eclipses occur when volcanic matter and aerosols are tossed into the stratosphere. With the moon’s brightness varying from one eclipse to another, it informs scientists of the state of the earth’s upper atmosphere. When compiling data and statistics eclipses are ranked using the five-point Danjon scale.

One will be in seventh heaven if they learn all that needs to be known to photograph the gray or brownish coloration, the deep red, rust coloured or the bright copper-red orange eclipse. Contrary to popular belief, photographing lunar eclipses is easy provided you have the right equipment. The light from the full moon is bright enough and very capable of illuminating ground objects while casting a shadow. As a result, one can use a normal camera to show the dramatic effects with trees, houses and people in the foreground if you wish. A sturdy tripod is recommended considering the exposure will be quite long. You will also need longer focal length lens.

A basic telescope with a camera adapter will give the astronomer some very lovely pictures of the lunar eclipse. More so during the partial phases. But for higher quality images of the entire lunar eclipse phase, one needs a telescope with guiding. This is needed because you will wish to use a decent size lens system as well as take longer exposures during totality which can be done without tracking. Most telescopes are designed for viewing not photography. With that in mind be aware of the possibility of ‘vignetting’. For very clear and consistent pictures of the lunar eclipse, use only middle 50% -70%. But this should also be based on the actual length of your focal tube and adapter assembly. Experience will determine just how well your pictures turn out.

When you take the image size of the moon into account, a 1000mm lens will produce an image which is 9mm in size. A 2000mm lens will result in an image of 19mm and a 2500mm will be 23mm in size. Therefore the maximum lens size needed to show the entire surface of the moon on the negative/slide is 2500mm. Extremely good images of lunar eclipses can be taken using a Meade ETX 90mm scope with T-adapter. Now the best views and images of lunar eclipses will include the whole moon of course. The actual shadow falling across the craters of the moon will be so subtle. Therefore a digital camera or video attached to the telescope will be the better option. Now don’t use too much magnification. Do plenty of research on photographing lunar eclipses and prepare yourself well. Dress comfortably, protect your eyes, organize the ideal safe viewing site and ensure that all your equipment is in tip top shape.

More about this author: Janette Waldron

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