Revolution for amateur astronomy
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Astronomy is a science that speaks to the imagination. Everyone is familiar with the spectacular photos that the Hubble space telescope has made, and not a few, with the thought of 'I would like to see that with my own eyes', bought an amateur telescope – and were bitterly disappointed.
Everything revolves around light
Those beautiful gas clouds, star systems ('spiral nebulae') and star clusters as so far away that only a very small amount of light reaches the Earth. It is therefore imperative to collect as much light as possible from these faint objects. And that can be done in two ways (which are usually combined): by using a lens or (these days almost exclusively) a mirror with a large diameter (that, as a consequence, can collect and focus lot of light) or by exposing a photographic film or image sensor for a long period of time.
And then it becomes expensive
This is therefore the reason that professional astronomical telescopes have a mirror diameter of many meters. For amateur astronomers such instruments are well out of reach; a good amateur instrument with a mirror of 25 centimeters and a price tag of around 600 euro is, however, reasonable affordable. And using this with the naked eye ('visually') there is much beauty to be seen – but Hubble-like images you can nevertheless forget: while it is true that you will see 'something', if you know where to look, but much detail can not be descried.
Photography
Here is where photography comes into play. By exposing a photographic plate for hours, a large amount of detail can be made visible. These days, amateur astronomers don't use film any more, but use electronic cameras instead, and these also do not expose a single image for hours, but make tens or hundreds of images that are subsequently combined in software (this is called stacking). In this manner (and with some experience) very nice images can be produced. You do, of course, need to have the correct equipment: the telescope itself, a good camera with accessories, and especially an extremely stable mount with a drive that ensures that the telescope remains pointed to the exact same spot in the heavens (the Earth rotates, after all). Before you know it, you are several thousands of euros later… Additionally, for good images a very dark sky is required, so that means very far away from the inhabited world. And it is really not all that pleasant to lug a heavy telescope and an even heavier mount on a cold winter night into a paddock in the middle of nowhere!
The best of two worlds
The young company Unistellar Optics has however succeeded in combining the best of two worlds. For about 1300 dollars you receive a telescope (the eVscope — eV means enhanced vision) with modest dimensions (11 centimeter mirror diameter) with computer controlled mount and drive, a high-quality image sensor is built in; instead of a normal eye piece with lenses, an eye piece with an OLED display is used.
The electronics continually makes short exposures, stacks these on top of each other and so simulates an instrument of much larger dimensions. In this way you can see for the first time with your own eyes and in real time what was until now the exclusive domain of (semi)professionals.
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