These are built in to some binoculars, such as my Fujinons. It is simply a vertical scale in the center of the image. There is a formula for converting how high up the scale the object of known height is to its' distance. I have tried this vs a chart plotter and radar, and it certainly gets you well within the ballpark if not exactly on base. You have to compensate for tide height in the case of some objects. Having a separate instrument for this is certainly the coastal navigation equivalent of carrying a sextant. In a lot of areas there are few charted objects of known height. -----Original Message----- From: "Faure, Marin" <marin.faure@boeing.com> Subj: T&T: Sextants Date: Mon Dec 5, 2005 4:10 pm Size: 1K To: <cruiser6003@yahoo.com> cc: trawler list <trawlers-and-trawlering@lists.samurai.com> >Joel said---- A much more useful instrument (and required learning) was the stadimeter. For those who haven't seen one, it is essentially a device for determining a distance to an object of known height I'm curious if a stadimeter would still be of value in some of today's boating situations.... For example, it's not all that hard to come up with a reasonably close estimate of the height of a bluff or a building on shore, etc. Would a stadimeter provide an equally reasonable estimate of your boat's distance from these objects? Joel mentioned using the stadimeter to set and hold distances between ships traveling in formation. These objects are pretty close to each other. Is a stadimeter sensitive enough to give a meaningful reading when trying to use an object on a distant shoreline as the "fixed" height? I know there are optical and opti-electronic rangefinders on the market, but the ones I've come across on a quick Google search have been pretty pricey-- $200-$500. On the other hand, I have no idea if stadimeters are even still made, or if so how much they cost. Are there any rangefinders on the market that are accurate but have a more reasonable price than the pretty fancy ones I've seen so far? ______________________________ C. Marin Faure GB36-403 "La Perouse" Bellingham, Washington [demime 1.01d removed an attachment of type application/ms-tnef which had a name of winmail.dat] _______________________________________________ http://lists.samurai.com/mailman/listinfo/trawlers-and-trawlering To unsubscribe send email to trawlers-and-trawlering-request@lists.samurai.com with the word UNSUBSCRIBE and nothing else in the subject or body of the message. Trawlers & Trawlering and T&T are trademarks of Water World Productions. Unauthorized use is prohibited.