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alan4908

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Everything posted by alan4908

  1. Thanks for the comment Peter Alan
  2. Located in Cygnus, I could only find a handful of images of this relatively bright nebula, so it appears quite a neglected target. What I particularly like are how the blue stars add colour contrast to the deep red of the emission cloud. This close up also reveals the dark structure in the central region. This LRGB image has an Ha blend into the red channel and represents 23 hours integration time, it was taken with my Esprit 150. Alan LIGHTS: L:27, R:21, G:20, B:20 x 600s; Ha: 17 x 1800s. FLATS:40, DARKS:20, BIAS:100 all at -20C.
  3. I also have the same weather sensor but use it in conjunction with ACP Expert. The Hitec Astro Weather has an ASCOM weather service object ID with the name HitecWeather.Weather - in order to set this up in ACP you simply tell it the ASCOM ID of the weather server and it then knows the state of the weather (Safe or Unsafe). Although I'm not familiar with Voyager, I'd have thought you be able to perform a similar set up. FYI - given the variability of the UK weather I use 20 mins before starting things again. Alan
  4. Thanks - I agree with your point on the detail, that's why I went for an imaging set up with the highest resolution I thought was practical for Deep Sky imaging given my local conditions - 0.7 arc seconds per pixel. Alan
  5. Thanks for the comment. On the tidal tail - I was expecting this to go all the way to the galaxy but it hit my noise floor quite a way out. I presume it still exists here but it must be much dimmer in this region. Thanks. Yes, I too really like how those HII regions have come out on the final image. Good luck with your future capture ! Thanks Peter. Thanks, I'm glad you liked it ! Alan
  6. Thanks for the comment Yes - that faint band of light to the left of the galaxy is the very long tidal tale . It doesn't often appear on images, probably because it is is very faint. As explained above, it was probably created c800 million years ago when M66 passed by and ripped stars and gas out of NGC 3628. Thanks - yes, I agree - I've often looked at images at this galaxy but never really paid as much attention to the amount of detail before. Alan
  7. Located in the Leo constellation, NGC 3628 is relatively bright, edge on spiral galaxy about 35 million light years away. Notable features are a broad equatorial dust band, which obscures the central region, and a very faint, 300,000 light years long, tidal tale of stars. It is also known as the Hamburger galaxy. The neighbourhood also contains two other large galaxies, M65 and M66, which together with NGC 3628 form the Leo triplet. Gravitational interactions with these galaxies are believed to be responsible for the warped disk and tidal tale. Spectroscopic analysis indicates that the s
  8. If you zoom in to a high degree on the unbinned (first) image you can see that all the stars suffer a severe elongation. You can also see that the noise is quite high and that the RGB colours and not quite correct. I suspect that the non-round stars are due to the fact that your guiding was not working and so the lack of roundness is simply a manifestation of your mounts tracking inaccuracy. If you look at the binned image, where you have decreased the overall resolution of the image, they appear more round. You can also fix this effect to a large degree in post processing - I'd sugges
  9. From the album: Deep Sky III

    See non-annotated version for description.
  10. alan4908

    Deep Sky III

    Images taken with a Trius 814 and a Esprit 150
  11. alan4908

    NGC 4449

    From the album: Deep Sky III

    NGC 4449 is a dwarf galaxy located in Canes Venatici, 20,000 light years across and c12.5 million light years from Earth. Its structure is similar to the Large Magellanic Cloud (LMC), the satellite galaxy to our Milky Way. Evidence for a very high rate of star formation is indicated by the presence of many young blue stars and pinkish star forming regions. It was the first dwarf galaxy to have an associated tidal stream identified which is the product of violent interactions with another satellite dwarf galaxy, NGC 4449B. The faint remnants of NGC4449B appear as a dim trail of stars and
  12. Thanks for the comment - if you do attempt this, then I'd suggest quite long exposures for the outer arms since I found them very faint. Alan
  13. Thanks Lee - yes, NGC 4399 is very strange looking - looks a little like a planet made of stars. Well, given poor UK weather and the fact that I don't have a clear horizon, it does take me rather a long time to get this amount of data. Due to these two factors, I do rely on my automated imaging set up a lot ! Thanks !
  14. NGC 4395 is low surface brightness dwarf galaxy about 14 million light years distant in Canes Venatici. Although visually dim, the apparent size of the galaxy is quite large, about 13’ x 11’. Unusually, it does not have a central bulge of stars in its central core and is significantly variable in X-Ray emissions with luminosity emissions varying by a factor of two within 300s. Three star forming regions, have separate designations (NGC 4401, 4400, 4399). Most galaxies contain central black holes and radiation is produced as objects fall into them. For NGC 4395, the core is extremely dim
  15. Good luck with your capture ! Thanks Paul. Yes, a long focal length helps and also small camera pixels. With my Esprit 150 and my Trius 814 camera set up, I'm at 0.7 arc seconds/pixel which gives me quite a high resolution imaging set up. Thanks for the comment Lee
  16. Thanks - yes , it doesn't appear very often on SGL, perhaps because of its small apparent size Thanks - its definitely worthy of more attention that it currently seems to get. Thanks for the comment. Thanks - if you are going to attempt this just be aware of its small apparent size. Thanks Peter. The tidal tail is very, very faint - even with my quite dark skies and 600s subs its only just above the noise floor . Alan
  17. Yes - a very interesting target - thanks for the comment. Alan
  18. Thanks for the comment Alan
  19. NGC 4449 is a dwarf galaxy located in Canes Venatici, 20,000 light years across and c12.5 million light years from Earth. Its structure is similar to the Large Magellanic Cloud (LMC), the satellite galaxy to our Milky Way. Evidence for a very high rate of star formation is indicated by the presence of many young blue stars and pinkish star forming regions. It was the first dwarf galaxy to have an associated tidal stream identified which is the product of violent interactions with another satellite dwarf galaxy, NGC 4449B. The faint remnants of NGC4449B appear as a dim trail of stars and
  20. alan4908

    m108

    Thanks ! Alan
  21. alan4908

    m108

    From the album: Deep Sky III

    M108 is a spiral galaxy 46 million light years distant in Ursa Major. It is inclined at 75 degrees from the viewers perspective, so the spiral structure is hidden from view. Visually it appears as a relatively small object (11.1’ x 4.6’) with an apparent magnitude of 10.7. Its core is estimated to contain a supermassive black hole with an estimated mass of 24 million solar masses. I was pleased to capture quite a bit of detail on the galaxy including the Ha emission areas. The background also contains many small, more distant, galaxies. The LRGB image below was taken with my Esprit 150 and r
  22. alan4908

    NGC1491

    From the album: Deep Sky III

    Discovered by William Herschel in 1790, NGC 1491 is a bright emission nebula in Perseus about 12,000 light years distant and about 21 light years wide. Despite its large size, its distance from Earth means that it appears visually small. The HII region displays a great deal of structure. The 11th magnitude white/blue type O5 star BD+50 866, located near to the centre of the image below, illuminates the nearby hydrogen gas with high intensity ultra violet radiation, ionising the gas. Material ejected by the star has also created curtain fold and half bubble effects in the surrounding HII r
  23. Thanks - yes, the galaxies, particularly the (annotated) background ones seem to be be particularly distant (c700m light years). If you look closely at the image, you can also see that Pixinsight did not pick up all these in the annotated image, maybe these are even further away Alan
  24. Thanks for the comment Michael. Alan
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