smallest compass w/magnetic declination adjustment?

[Sam Farrington]

Good info here. Thanks.

Above timberline, often the compass headings are used in conjunction with the ‘handrail,’ technique, which has been often discussed on BPL.  A problem is that the faded green to note timber line on the USGS maps can fade, either on the original or when copying, or using commercial copies like Nat. Geo., which also have various errors.  Many of the plastic map materials are also particularly prone to fading.  Then the handrail is gone.  So reluctantly, the USGS paper map can be cut  to desired size, and laminated in a very thin (1.5-3 mil) material.  Then the timberlilne remains clear for a few years at least, and the map remains dry.  Many of the USGS 7.5 minute series have not been updated for over a decade, so thanks for the link to the declination update site.

[Roger Caffin]

How odd.
I have (Australian) topo maps from the 60s which have not faded. Does USGS have some sort of ‘planned obsolescence’ thing?

Cheers

[Boyan B]

The Brunton Truarc 3 is not worth even the low price they ask for it.  First, there is no grid on the bezel to align to the map north.  Sure, you can set a “tool free” declination correction, but they you have absolutely no way to transfer headings from map to field or field to map without severe eyeballing.  There is a pathetically inefficient attempt to remedy this via two thin black lines on the bezel, but they are just woefully inefficient for the job.  What is the point of having declination correction then?  Second, the scale is on top of a rather thick bezel, so paralax errors when reading or setting headings are a real possibility.  Third, the lettering on the bezel looks like it will wear out in a few weeks jostling about in a backpack.  Finally, the “global needle” is a joke.  In a side by side test with the cheapest Suunto (the A-10) the Brunton needle stopped tracking before the Suunto.  I bought this today from REI and it is going back.

[Sam Farrington]

Hi Roger,
What fades on the USGS maps is the already faint light green shading below timber or tree line, so it is necessary to cut out and laminate sections of the map to keep the shading distinct. Perhaps they have more distinct shading in digital form. But paper will not hold an image very long on a rainy day in the Rockies.

Knowing where timber line is on the map shows where I am in areas where the trail has become ‘undefined.’ A good example is the section of Colorado’s Never Summer ‘trail’ from the col east of Seven Utes Mountain south to Silver Creek. The route crosses from State Forest to National Forest just south of the col. After that, the only guide to the route is by keeping 50 yards or so above the timber line for several miles until reaching a series of defined switchbacks that lead down to Silver Creek. There was an article on BPL a few years ago about this ‘handrail’ technique being used in the Wind River Range in Wyoming. But without the shading showing timberline on the map, it is not possible to spot in advance areas where the technique can be used.

As for “planned obsolescence,” these days not many ever keep anything long enough for it to become obsolete. The rest of us do MYOG, laminating maps etc.

[Roger Caffin]

I have no trouble accepting that the green ink has faded. My only point was that the choice of ink by the USGS was pretty crap.

Cheers

[Sam Farrington]

Got it. That’s not all that’s pretty crappy these days.

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