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Laurent has sent some images that shows the new feature he has incorporated to his telescope. It is a thermal sensor. It is used to measure accurately the temperature of the mirror and of the environment. That way he tries to avoid thermal issues in his planetary images, reducing as much as possible the gradient of temperatures between his telescope and the surrounding air. This technique has been employed to acquire the Jupiter picture we see here.
2015-11-13 12:33:45       
Any person that did not maagne to sit on a chair has to quickly run for the safe zone while leaders (or selected young people) throw the balls at them. If they make it to the safe zone without being hit, they are free to play the next round
2015-10-18 15:57:53       
Good point, as I have used a plasma cutetr a lot and always wear gloves, although thin leather ones. I suppose the thin sheet metal is using less amperage than I normally use for around 1/8 to 1/2" steel plate and 1/4" aluminum plate, but even so I have sent quite a few flying balls of molten metal about and would not be doing this w/o gloves. Now, with a normal cutting torch for thin stuff I will go w/o gloves for small projects.
2012-10-07 23:34:13       
Why Because they catch a lot more light and they have very sensitive cemaras, and they can track the object with extraordinary precision, using very precise filters.Each picture is taken in black white, with very specific filters (classical = red, green, blue and full spectrum). Each picture is then added using a computer program that balances each color based on the amount of luminosity that was detected through each filter.In our backyward telescopes, we tend to look with our eyes. Our eyes have two separate systems to interpret light: rods and cones.Cones come in three lengths, with each length sensible to a different range of color. Combining the signals from each set of cones, our brains are able to rebuild the color of the object.Rods are far more sensitive than cones, but carry no color information at all (they are full spectrum ). Signals from the rods are interpreted as white (or gray, at low level). If the brain receives signals from both systems, it relies mostly on the cones for the final image.Nebulae are very weak sources of light and, in our backyard telescopes, this will trigger only the rods. Hence they are seen as grey.In most people, the cones that are sensible to green are a bit more sensitive than the cones for red or blue. That is why some of the brighter nebulae are often reported as greenish when observed visually.In a large enough telescope, some of the brighter ones do show some red (e.g., the Trifid Nebula).
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