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davhei

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About davhei

  • Rank
    Nebula

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  • Location
    Sweden
  1. Having never done any AP (yet), sticking to visual only, it is interesting to consider what makes an impact on me when observing through the eyepiece. A number of occasions come to mind, seeing Jupiter in high magnification revealing cloud bands and the galilean moons, the veil from a dark site, crisp lunar vistas with long shadows. Oddly enough, and perhaps fortunately considering the limitations of visual astronomy, the less striking objects are often those that have stuck with me the most. I recall vividly the profound feeling of space and time suddenly becoming clear in my mind when seeing a few photons from a distant quasar. The realization that light emitted billions of years ago from the accretion disk of a black hole was destined to be absorbed by my retina in a different part of the universe. The feeling of getting a glimpse of the vast reality beyond the limited point of view that we usually have in our daily lives. Of our place in the universe. Truly a spritual experience. That feeling doesn't come all that often, but when it does it stays with me and is certainly part of the fascination I have with observing the skies.
  2. That is an absolutely magnificent sketch. Did you use ink? The stars look jet black and very rich in a pleasant way. Sure you will make many more great sketches if you continue like this. Really adds another dimension to observing, go for it! Edit: Right I see the pencil now, nevertheless a nice deep look to those stars.
  3. I use an app on my phone. There are probably many out there but I use pixlr. I first snap a picture of the sketchpad, preferrably in overcast daylight, then adjust the colours to zero on the phone image editor to get greyscales. Load the image into the app, make a few adjustments to contrast and then invert the colours. A more ambitious person could probably work miracles in photoshop but sadly I am not one of them.
  4. davhei

    Mayall II

    Fantastic! Makes me very glad that I was able to inspire and that the sketch actually helped. In general I have found that people’s sketches at the eyepiece are a great aid for visual observation, perhaps more so than images of the same object, simply because they provide good references for fields of view and magnitude of visible stars.
  5. That’s an awesome suggestion and a what a tutorial! Thanks for this Ruud, much appreciated!
  6. Thank you Ruud. Yes indeed, it really adds a dimension to observing. I see some people add a touch of colour to their sketches as part of the finishing at home. Have to try that at some point, probably fairly simplistic on a phone app, me not being into photoshop and the like. Looks great for colorful stars.
  7. Thanks Rob, a toothpick really helps to get the thin lines. I believe someone on this forum provided the inspiration, can’t recall who it was though. Anyway it works well and I will thank that person if I run into the post again.
  8. Made an attempt to sketch a few of the brighter stars, seeing as the full moon was out and the sky wasn’t suitable for deep sky observing. Experimented with diffraction spikes on Vega, Capella and Arcturus to get a nice bright look to imitate the view through the reflector scope. Overall very enjoyable!
  9. davhei

    Mayall II

    Brilliant! I recall that you inspired me to observe quasar PG 1634+706 in draco. If you could see that then Mayall II should be a breeze.
  10. davhei

    Mayall II

    Thank you for your kind words! Not sure I deserve all that much praise on the observation skills, it mostly boils down to aperture and dark skies I think. 90 mm does seem a tad on the small side for this object though. As a side note, the deepest I've gone with my scope setup is in the range of mag 14.4 +/- 0.2 for a quasar and thereabout I think is the limit for my location. You are spot on, 254 mm or 10 inches is the mirror size and 1200 mm is the focal length. The technique is also just like you guessed, a blending stump to create the diffuse effect and a soft pencil to get the graphite for the stump.
  11. That is a beautiful sketch, very inspiring! Thanks Jack.
  12. Welcome from a fellow swede. Enjoy stargazing in the coming dark season during the precious few clear and cold nights. Oh, northern europe certainly presents challenges for the aspiring astronomer.
  13. davhei

    Mayall II

    To begin this year’s dark season I wanted to try something faint in order to really get the feeling of dark skies again. Have had the andromeda galaxy globular clusters on my list for a while and decided to give G1 or Mayall II, the brightest one, a go. Finding M31 wasn’t difficult and even though G1 was surprisingly far from the core regions it was still a fairly easy star hop. Had prepared detailed charts beforehand and that certainly helped. The difficult part was identifying the triangle asterism with two stars in one corner, a faint star of similar magnitude in the second and G1 with a magnitude of 13.8 in the third. Once dark adapted it was a distinct but faint averted vision asterism but I found that at higher magnifications I lost it a couple of times and had to start over with wider field EPs. Mayall II appeared starlike at first, and after a while I thought it took on a slightly diffuse appearence. Either from the two faint stars close to G1 or from that it had an angular diameter greater than a pinpoint star. Could never separate the glob from the two stars for certain even though I may have glimpsed it at times. Or not. Could have been tricks of the mind. Spent some time on this object and found it really enjoyable. First in a session a few days ago and then again yesterday when I made a sketch as a keepsake. Had major dew problems on the secondary mirror though that made sketching more difficult. Shall have to try the fainter M31 globulars as well, maybe doable but would certainly stretch the limits of the scope and myself.
  14. After reading up a bit more, it seems that after the core collapse in the progenitor star, matter can be expelled at velocites close to 0.1 times the speed of light. After hundreds or thousands of years it gradually slows down to the speeds initially mentioned, such as the 40 km/s that purportedly had been measured in the Veil today. So the changing speed is key, meaning the shockwave covered a lot of distance in the beginning and the slower remainder of it energizes the nebula today, some 50 ly from where it started. Fascinating stuff. Again, just trying to piece things together in an amateurish way. Please set me right if I’ve gone way off the mark.
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