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Rating: 5 / 5
The Brunton (Silva) combi 54 is the best all around compass I’ve seen. Overall, it has proven itself better than my old Suunto KB-14, commonly regarded as the most accurate sighting compass around.
The problem with most sighting compasses is that one needs a separate tool for translating that accuracy onto a map, and my homemade protractors never equaled the Suunto.
The problem with flat base compasses is that acquiring consistently accurate bearings is more an art than a science. Ray Jardine says in his Pacific Trail Guide that a skilled person can get 1.5 degree accuracy with a common base compass. After experimentation I found that’s just what I could get. The problem was that one out of every dozen or so of my readings was off by 2.5 degrees, and more rarely even as much as 5 degrees. Vigilant practicing did not improve my results.
The hinge mirrored compasses represent a pretty good compromise, but their short base length limits ease and accuracy on maps, while their tilting mirror sighting adds some ambiguity to field bearings.
The Silva and Brunton (same compass – different brandings, as Silva now owns Brunton) combi 54 is a very lightweight accurate map and field compass. Its length measures nearly 5 inches, compared with 3 inches for my Silva 16 mirror compass. To sight with the 54, one looks into the small window on the rotating dial. A mirror built inside the liquid filled dial directly reads out degrees on a vertical sight line. Everything is internal and there are no moving parts beyond a standard base compass. Readings and backbearings are marked in degrees and thus consistent half degree bearings are easily achieved.
Like my KB-14, I’ve mounted a small cotangent table on my combi 54, and with it I can do some fun things that not even my GPS can. By walking a long enough baseline, I can estimate the distance to a distant landmark. If interesting landmarks are off your field maps, save your bearings to identify them once you are home.
One last point is the amazingly bright glow in the dark points, which permit full sighting and mapwork.
Nothing is perfect, and a listing of a few downsides is in order.
1. Expensive – I paid $60 at Kooters. (http://www.kooters.com/reccomp.html)
2. Three base feet rather than 4. (minor)
3. The large NSEW dial points are nice but take space better made available for map work. (minor)
4. There is no declination adjustment. I’m in Colorado, declination about 10 deg. East, so First Man Adam = Field to Map, Add. A better trick may be to draw magnetic north lines on your map, spaced a regular distance i.e., ½, or 1 mile intervals. Don’t forget to update, since declination is now changing rapidly.
5. My most important scale is missing, namely the 1:40680 scale of those great Trails Illustrated Maps.
6. Though sighting is to ½ degree, the dial has no magnifier like some premium baseplates, so you can’t get map work better than 1 degree. (probably minor point)
7. Light but no ultralight, at 1.3 oz w/o lanyard.
In all, a rather common looking compass with the best feature set and precision I know.
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