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Archives of an email list on the history of binoculars. - page 90 / 150





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off-white rubber armor for artic warfare and had neutral density filters in place of the laser filters. Given the nature of how the sticky M-22 green rubber would attract dirt, I can only imagine the light brown color they would have become after several weeks of use.  The Steiner presentation case was probably the best home for such an un-stealthy binocular.

May the M-22 rest in peace - or pieces!

All Best Wishes,

Steve Harris



Subject: Explaining Binocular "Reach"

From: Kennyj2@___m

To prevent possible further charges of causing death by dubious definition I will try to clarify what was intended by my use of the term " reach" in previous correspondence.

Both the words "reach" and "experts" were deliberately placed in inverted commas to highlight the context in which the words were used , namely both being expressions chosen not by myself , but by the author of a very popular website specialising in reviews of optical equipment of a non -astro nature .

I thought it prudent to withold the name of that website.

To lesser mortals such as myself the term "expert" could indeed be applied to a range of persons varying from rightfully respected optical designers and repair persons such as contribute to this binocular group to anyone who actually gets paid for writing about binoculars and/ or telescopes .

It is amongst the latter group that I have occasionally come across the expression"reach" with reference to the maximum terrestrial distance at which resolution of a given detailed object can be achieved through any given optical instrument .

Of course conditions of visibility and human eye acuity play a much more important part in the overall picture , but in what I presume to be it's most commonly intended meaning the term"reach" would be a function of magnification rather than objective size.

For example it might be observed that the time on a Church clock 6 miles away can be clearly read looking through a 10 x 40 binocular but not through a 8 x 40 and in such an example this would clearly be due to the extra magnification.

What the author of the article I originally referred to and what other writers on the topic have  agreed with is the implication that there can be situations that enable such positive identifications to be confirmed through say a 10 x 50 binocular that cannot be through say a 10 x 25 compact in the same conditions.

Because this point seems to have attracted much interesting discussion in other places I just thought that it's mention might stimulate similar responses amongst a few people for whom I have nothing but the highest regard and respect .

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