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  1. B

    - Magnification and move vision:

    The image of the chimney pot at 124m in bright morning sunshine using a hand held 25x70 Skymaster was bright and large, but not too bright. However, it quickly became silly because of the movement. The sensible thing would be to tripod mount the 25x70 for viewing at 100m or more. Or just use my...
  2. B

    - Magnification and move vision:

    I thought you are talking about binocular movement. If the binocular amplitude due to hand movement or shake is 120 arcseconds then it is 120 arcseconds for any magnification. With the same binocular, but various magnifications. An eyepiece lens could be removed. It would still be 120...
  3. B

    - Magnification and move vision:

    Hi Peter, With the Canon 18x50 IS I gain 1.5 magnitudes on faintest stars when the IS is switched on, compared with switched off. That is 4 times fainter. The faint stars are tiny. The same with most of the Canon IS and other stabilized binoculars. I could not read a hotel sign with my...
  4. B

    - Magnification and move vision:

    In the above tests in bright sunshine the 8.5x44 binocular was probably acting as an 8.5x22 binocular. The 25x70 as a 25x63 or 24x60. The 15x70 as a 15x38. The coarse detail was better seen in the 25x70 than in the 8.5x44. The coarse detail was about the same in the 15x70 and 25x70. This coarse...
  5. B

    - Magnification and move vision:

    Test 2. Thought this was the 25x-135x80, but unboxing it is the as new Helios 15x70 Waterproof long eye relief binocular. I think this is the Quantam under a Helios name. This 15x70 is high quality and heavier than the Skywaycher 25x70. It is rubber armoured. The Skywatcher 25x70 has a foam...
  6. B

    - Magnification and move vision:

    Test 1. 10.45 a.m. 25x70 Skywatcher. Chinmey pot 124m distance. Bright sunshine. Eyecups folded down to minimum. Initially very unpleasant holding body with two hands. Then held end of left barrel with left hand and right hand holding the body. Steadier but still unpleasant dancing of image...
  7. B

    - Magnification and move vision:

    Post 71. The 120 arcsecond movement at 10x will still be 120 arcseconds at 100x, not 1200 arcseconds. The crab nebula pulsar has a pulse time of 30 per second. A decade before it was discovered a female member of the public at an observatory public showing said that the star was pulsing. The...
  8. B

    - Magnification and move vision:

    Familiarity with the target helps with glimpsed views. We have persistence of vision, even without a photographic memory. My understanding is that photographic memory needs more than a fraction of a second. In the 1950s when nearly all aircraft looked different, I could reliably identify...
  9. B

    - Magnification and move vision:

    Pileatus, Nice mount and counterweight. I suppose the controller is to bring the binocular to the eyes. (: Regards, B.
  10. B

    - Magnification and move vision:

    I just counted up as many 15x and higher magnification binoculars that I have actually used for either terrestrial or astro observations. These are all different types not duplicates. I am currently up to 31 different types. There may be a few more. I am not unfamiliar with high powered...
  11. B

    - Magnification and move vision:

    Gijs, post 35. I am with you here. 3 times larger, 25 times compared to 8 times. Yes it is. 3 times more detail than 8x. No it isn't. At least not hand held. I have no objection at all to anybody using a 25x70 binocular hand held unsupported or braced. But to say that 3x more detail is seen...
  12. B

    - Magnification and move vision:

    I will give personal thoughts here. I cannot see through other people's eyes, only my own eyes. In general, I think that the oscillations from hand holding a binocular are a rough circle with possibly additional darting movements. As the magnification increases the apparent size of the rough...
  13. B

    - Magnification and move vision:

    I was using the Canon 10x42L IS yesterday, and in connection to the best of the best thread, I would say that this is it. However, it is heavy and bulky, so maybe only the best of the best for the fit and strong user. Looking at the chimney pot at 124 metres, unfortunately without the magpie...
  14. B

    - Magnification and move vision:

    A very short sighted or far sighted person won't see much without glasses. Wearing glasses alters the magnification. Wearing glasses using a binocular alters the marked magnification of the binocular. I use a binocular without glasses. However, if I wear glasses I increase the magnification...
  15. B

    - Magnification and move vision:

    Since about 1960 the classic focal lengths of astro telescope eyepieces has been. 4mm, 6mm, 9mm, 12mm, 18mm, 25mm and 40mm. This suggests to me that the step for providing increasing magnification is about 1.5x not 1.8x. I happen to have about 9 other focal length eyepieces to meet my needs...
  16. B

    - Magnification and move vision:

    I wasn't going to comment, but I'll give practical thoughts. Firstly naked eye vision is not always 1x. If people wear glasses it is perhaps between 0.85x and 1.18x. An eye specialist might advise. Each eye may have slightly different magnification. Secondly, while observing sunspots with...
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