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    Which binoculars are less stressfull for the eyes?

    Binoculars are probably limited to 100x because of collimation problems. Unless you include the enormous Alvan Clark? 6 inch binocular telescope, which probably had the same limits as the 6 inch telescope. My friend made several 150mm binoculars using 150mm f/8 Chinese scopes and mirrors...
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    Which binoculars are less stressfull for the eyes?

    Jerry has a point. But Jerry is not a Moderator. He has also not posted personal comments about me for a long time, and I appreciate that. Regards, B.
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    Which binoculars are less stressfull for the eyes?

    All fine refractors have objectives that rattle a bit. If they don't then the elements are too tightly held and pinching results. If the refractors are actually used then the elements rotate by themselves. Here, triplets have a problem. One, two or three elements may have rotated from best...
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    Which binoculars are less stressfull for the eyes?

    Post #53. A fine 102mm f/8 triplet will be somewhat better than a 102mm f/8 doublet. But firstly, not all achromats are made from the same glass types. My custom refractors were probably aspherised. The Tal 100mm f/10 refractor is highly regarded. My Pentax 100mm f/12 was a doublet, but...
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    Which binoculars are less stressfull for the eyes?

    It depends. At 420x with a 6 inch long focus top quality achromat detail is great in excellent Seeing. An Apo helps but isn't essential. My 120mm refractors are great at 300x, non Apo. It depends more on how good the optics are. Regards, B.
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    Which binoculars are less stressfull for the eyes?

    The reason the line of cars wait while the Ferrari is backed into the garage is that it may take several minutes blocking the whole road. The turning circle is large, and positioning it difficult. So being gentlemen they wait rather than force the Ferrari to stop. Yes, some cars are babe...
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    Which binoculars are less stressfull for the eyes?

    There is a one year old Ferrari next door 20ft from me. To me it is a dinosaur. Getting into the garage space is like parking the space shuttle. The cars in the street stop respectfully to see the machine back into the garage. It is difficult to see from the driver's viewpoint. I suppose it...
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