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Message: <blockquote data-quote="Surveyor" data-source="post: 3574428" data-attributes="member: 50720">Hello Henry, hope you had a nice vacation.Have you used a NBS 1963A target? I find they have the advantage of longer lines but I find them very hard to use on boosted optics. The USAF 51 target is nested so as you zoom in the relative position stays the same, with the NBS target when you change groups you have to reposition the target, a real pain in the neck.Like you said, the price is out of the question for the average bino tester. Using Edmund as a relative reference the following are for comparative purposes:A group 1-18 mm/lp target (USAF group 4 element 2) is $200.A group 1-180 mm/lp target (USAF group 7 element 4) is $275.A group 1-512 lp/mm target (USAF group 9 element 1) is $750.Note the above prices are for a single image.A USAF from Edmund’s that goes to group 9 element 3 (645 lp/mm) is $625, single image.For amateur use you can get a very decent target from China for $80-$100 that has both positive and negative vapor deposited images. I actually paid less recently for a couple of these.<a href="http://www.ebay.com/itm/322346775033?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT" target="_blank">http://www.ebay.com/itm/322346775033?_trksid=p2060353.m1438.l2649&ssPageName=STRK:MEBIDX:IT</a>Or just search “resolution target”.I have used the NBS 180 lp/mm target and do not get any noticeably different results in boosted images than I do with USAF, so unless you have a professional need for a specified target, I would not recommend the spending the difference but you may be able to find a NBS 163A from China or elsewhere for considerably less.</blockquote>

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