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Alexandros

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  1. Thank you for your replies! I was thinking of getting the star hopping book before I developed this new interest, so I think I will get that!
  2. If you wish to start from basics, the Backyard Astronomer's Guide, 2nd edition by Terrence Dickinson and Alan Dyer is a good starting point. I've heard great things about Nightwatch by Terrence Dickinson as well, but it is a little bit more basic than my other suggestion. Kind regards, Alexandros
  3. Hello all, I've recently developed an interest to learn about the star lore, the different cultures and civilizations developed and used over the years. Could you recommend a good book or site/ educational videos on this subject? (Sorry if this is the wrong forum, I was not sure as to where to post this question :) )
  4. OK, so for now my objective is to get a new barlow, possibly something a bit cheaper than the one suggested by alacant 😛 . I was thinking of getting this one from skywatcher https://www.planitario.gr/barlow-2x-759.html (there is an english version of the site on the top right that you can access if it is not already), which appears to be better from the one I already have. Do you think that this will reduce the abberation to imperceptible levels for my scope, or should I go for something else? I would certainly like to shorten the barrel of my scope but I am sure that would void the warranty, wouldn't it? Also Alan, when I reach that point I will most certainly ask you for help. I will probably have some good photos to share by that time
  5. Hi all, thanks for your replies! I do not think my problem is atmospheric dispersion, I think I am a little too inexperienced to even hit that limitation with my current cheap equipment. It looks like lateral chromatic aberration and generally bad quality of the Barlow that is limiting me right now. When I mentioned Venus, I noticed that the colour fringing changed when I was looking at Venus from different angles, which is the symptom of a simple lens if I am not mistaken. If it was atmospheric dispersion, should the colour fringing be the same no matter where in my field of view I had Venus?
  6. I think you just broke my brain with the focal length 😛 . I have to think about that!
  7. Thanks for your suggestions Alacant. I think I will go with the better Barlow for now. I don't think I am ready to modify my scope as of yet, maybe when I get a new one I will get back on that 😛. Wouldn't that also lead to a decrease in focal length as well as the aperture of my scope?
  8. Quick session for astrophotography, it appears that the culprit was the barlow. I can see the abberation getting worse in the edges when I was pointing at venus and moving the scope slightly. Also I could see it going from red to blue when I was defocusing to one side and then the other. So it is definitely a refractive issue there, which must be the barlow. So now I am stuck with a three way dilemma. Should I a) Buy an adapter for afocal photography? b) Get a better barlow? c) Get a shorter focuser? What do you suggest as the best course for right now?
  9. Wow that looks great! I will try to learn that software and try to do it on my own next time! I want to try stacking but as I don't have a tracking mount I don't know if it will be easy to do. Also finally, the sun just went down so I'm off to set up my scope and try again!
  10. Hi Pompey Monkey, thanks for your reply. Yes I was thinking the same thing, however my scope has a spherical mirror so I don't know the effects of that in astrophotograph. I have tried cleaning my barlow today, in order to make sure there was nothing blurring my view. I will try again tonight with the eclipse and see what results I can achieve.
  11. Hi Terry, thanks a lot for the answer. I agree, the photo does not look focused, I will try next time to play with the focus a little back or front from the point I was last time, just to be sure. The eclipse should be fun to try and image as well. However, one thing to mention is that my mount is not tracking and does not have any motor to correct for the rotation so I attributed the lack of focus to the motion of the sky. I tried to compensate for it by using a fast shutter speed, 1/250 and high ISO. Should I got for a faster shutter speed? Nevertheless, I will try again tonight and report my findings. Collimation on the other hand is something I did not consider. I am not very proficient in that matter, so that could be the issue. Could it be sensor bloom as well?
  12. Hello everyone, I just yesterday received the equipment I was missing in order to start taking short exposure prime focus astrophotographs and I set it up last night in order to get some photos of the moon. After a while of figuring out how everything fit, I tried to focus up the image using my cameras live view and zooming in the display to make sure the focus is as good as it can get. Focusing was not as hard, as I had read that with my scope, an 130/900 skywatcher explorer newtonian scope, a barlow lens is necessary as there is not enough inward travel on the focuser. After verifying image was focused I took the picture and to my surprise the colours seemed to have been focused differently, or somehow refracted after taking the photograph. This was not visible in the live view feed on my camera beforehand however. Specifically the blue colour seems to have been the most unfocused as you can see it fringing on the edge of the moon, as well as if you zoom in the ridges and edges of the craters, in the photograph I took yesterday, you can see all the spectrum of colours appearing there. I am using the barlow included in my scope which might be of bad quality so I think the issue is that, but I would like your opinion as well. What do you think the problem is?
  13. I am waiting impatiently for your report! Happy sightings! Alex
  14. I wish I could see that but, seeing the aurora as south as down to Greece, that would be very disturbing! I am planning to see it at least once though it's on my bucket list.
  15. Ahh thanks for sharing your experience! Sadly a 12" scope is way far from my budget right now, let alone a 16". I still want to get a good solid go-to mount first because while it is fun to star hop, when you are in light polluted skies, the experience is not that enjoyable!
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