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Message: <blockquote data-quote="matthew_" data-source="post: 3379792" data-attributes="member: 137083">Thank you for sharing. I will try to travel farther and look for other optical stores later this week.Not only will I look for spectacles with correct IPDs. I will make sure the multicoatings will be properly done. When you look at objective lens of binoculars.. you can see deep red or deep green or even blue. But when I put my hands on the back of my spectacles and looked at the front.. the multicoatings were only very very light and didn't look deep green. If each surface has 4% reflectivity without multicoatings.. you get 8% loss of light in spectacles with 2 sides. But transmission is not the main problem.. you will also have lights reflected back to the eyepieces lowering image contrast. Do you know the  percentage of light loss in spectacles? I don't think it is 0.02% for each side which Swarovski claimed in their Swarotop. I guess mine has maybe 2.5% light loss because of very light coatings. Furthermore.. do you know the transmission spectra (I learned this jardon reading other threads by a poster called Gijs) of spectacles? If it is optimized for green light and suppressing other spectra (blue and red).. this can interact with the binocular spectra resulting in loss of contrast. So with the 95% transmission Zeiss HT, it will be lower to 90% transmission with spectacles.. furthermore, the 5% loss light would return to the eyepieces forming ghosts or lowering image contrast. Lastly. Plastic lens by itself is not as clear as glass lens. Do you know why? Thank you very much.</blockquote>

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