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Take the Shot

In Astronomy by Brian Koberlein0 Comments

This image was produced from a series of long exposures by Petr Horálek, and it captures a range of astronomical objects in a single image.

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National Geographic Effect

In Astronomy by Brian Koberlein3 Comments

You can see this effect in the image above. On the left is a Voyager II image of Jupiter’s great red spot as it appeared in NatGeo and elsewhere. On the right is the same image in its more true-color form. You can see why the colors were boosted. The true-color image lacks much of the depth and richness we like to see in images.

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Star of Bethlehem

In Astronomy by Brian Koberlein0 Comments

When stars are portrayed in media, they are often shown with long spikes emanating from them. Perhaps the most common example is that of the “star of Bethlehem” which, according to the story, led the wise men to baby Jesus. Of course when we look at stars in the night sky, we don’t see any such spikes. Stars twinkle due to atmospheric disturbances, but that’s about it. In photographs, however, bright stars often have such long spikes. So what causes them? It all has to do with an interesting bit of optics.

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Shades of Gray

In Astronomy by Brian Koberlein1 Comment

Despite all the wonderful color images we have from the Hubble space telescope, there is no color camera on the Hubble. The main reason for this is scientific. When observing astronomical objects, you’d like to get as much light as you can from the object. You also want to get as wide a range of wavelengths as you can.

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Having FITS

In Astronomy by Brian Koberlein1 Comment

For scientific imagery you want the data your camera gathers be “raw.” In other words, you don’t want the image to be compressed or manipulated in any way. For this reason a different image format is used, known as the Flexible Image Transport System, or FITS.