Green Baron

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About Green Baron

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  1. Some point to Russell's teapot with a stern mine, others, wearing a grin, paint Alabama teapots while Picard's aunt Adele is ready to serve the famous ginger tea. A horrible swill that coils up your toenails ... :-)
  2. Rome, the eternal city ! Cheers from La Palma, a greean island in the atlantic ocean. Gain and offset don't tell me nothing. My camera doesn't have these settings. It can only take pictures at a given temperature for a given exposure time. I assume they are settings for the signal amplifier/processor to do something ? Like ISO settings on a dslr ? What i know from dslr photography is that a chip has its highest dynamic range (in terms of light values, lv) when the signal is unamplified. That means for a dslr, if a chip is designed with an iso of 200, it will have the best performance at iso 200. Every higher setting will make things worse, like the noise is equally amplified with the signal. Good luck !
  3. The earth does actually as well draw a tail of gas behind it on its orbit and thus looses a small amount of gas constantly. Atmospheric gases (as well as many other elements) are constantly renewed and exchanged in the course of the various geological cycles on earth, in this case plate tectonics play a presumably vital role in storing and releasing elements over medium- to long term cycles (e.g. Wilson cycles). It is all not that easy ... :-) Edit: the earth's gas tail is mostly lost because it is blown away by radiation pressure from the sun. When the earth comes next year to look for it it is up and away :-)
  4. We must wait. Until then: Tea. Earl Grey. Hot.
  5. Anyone still asking him-/herself why no aliens come visiting us ?
  6. And look as intelligent and prudent as the four gaw err guys in the picture ?
  7. @Epox75: it seems that there is less noise and the filaments are clearer than in the 30sec exposures, what do you think ? Now with 2min exposures the nebula might even be clearer. Yeah, stars are overexposed. There is nothing one can do i think ... There was an open sky this morning, i saw the galaxy high in the sky. The next two days we'll have a phenomenon called Calima, that means high moisture and a lot of desert dust in the lower atmosphere. Thereafter we'll see :-)
  8. It condensates again. But i have hopes for the second half of the night. Well, one of your suggestions, why not, Crescent or Northamerica nebula. The first has 18*12min and is rather small, i have the reducer mounted now. Also i haven't tried to run guider and framegrabber on the "new" old eee pc i got. I mean, they start and ask for the cameras, that's a good sign. Will keep you informed :-) Isn't that a famous last word, attributed to the captain of the submarine Thresher short before it sank ? Edit: yes, it sadly is.
  9. Thanks for sharing. So the guy says that because of the low read out noise of the camera and a high background lighting you should use short exposures. Hmmm ... *rubchin* i am only a beginner like you but that doesn't seem logical to me. I would just try it out. Worst thing that can happen is that i will have learnt something new. But wait ... 2min for the RGB at f/4 ? That is more or less the same as my 4min at ~5.8, even a little longer. And L should be at least as long as the colour channels because L defines the fine structures. Be it as it my, i am going to put my stuff outside now for cooling.
  10. @Epox75: less is more. Really. Try fewer but longer exposures and you get a better snr. Like 20*2min or so. The center may be overexposed, so you can combine like 10 * 30sec L only. PixInsight does it right then (hdr-wise). I did the same with my M42 I have done a better version in the meantime without those artifacts and satellite trails, but i don't find it. It's 10*4min LRGB plus 3*1min L (f/5.8). Darks and biases. @munlander1: no. But for an f/4 it is very small.
  11. The article is a little misleading. What they call a gyroscope (Hemispherical Resonator Gyroscope) is only for measuring the bearing and it does so electrostatically. It has no moving parts and is, if manufactured thoroughly, very accurate and long lived. For actual aiming jwst of course must use a reaction mass in the form of moving wheels. Thrusters aren't applicable for that purpose, they are for long term station keeping around the lagrange point. Magnetic bearing isn't applicable out there, earth's magnetic field is too weak and a little "biased" towards earth :-), the sun's is too variable.
  12. Are we exchanging positions ? 28N/18W. As to Epox' suggestions: I am fine with those, only if they are too hig h in the sky exposure time will be limited as the camera might hit the leg of the mount.
  13. The information about the motivation, purpose and instrumentation of and for the jwst is on the jwst web site: https://jwst.nasa.gov/ Exoplanets are not jwst's main purpose, though new questions will surely come up with it's discoveries. Exoplanets are better done in the future with big ground based telescopes with 30 and more meters diameter. No telescope can actually take a photograph of an exoplanet (if it's not a giant Jupiter far from its star in planetary disc perpendicular towards us). That star flickers, and the period and intensity of the flickering *alone* is what lead to the planet discoveries of the Trappist-family.
  14. That is a question a cat owner waiter must bear :-)
  15. Not wildlife, in contrary. News from domestication, one of my favourite subjects. Today, CATUS, the domestic cat, wild form Felis silvrestris ... lybica. http://www.nature.com/articles/s41559-017-0139 I asked my cat whether she remembered hunting in the dry Northafrican sands. Apparently not, she stood up, stretched, walked to the food plate and looked at me as we would look at the waiter when our mug is empty. Wildlife, eh ?