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Hiking Gear
I have a fanny pack that I carry my Canon Vixia camcorder in with two 16oz water containers. I carry a 24oz Bubba thermos of water in my backpack as well. When I plan a longer hike I carry another 32oz thermos of water in my backpack. I carry my Pentax K-50 camera around my neck usually with the Pentax 50-200mm lens attached. I have two more lenses in my backpack; a Pentax 18-55mm lens and Sigma DG 70-300mm lens. I carry two compasses, one which is embed in a whistle for emergencies. I carry a small buck knife to whittle my name in a tree in case I kill a bear ;o)
And now I will carry the eTrex 10. Notice that each photo in the photo album has a number in parentheses that corresponds to the map below. These are the waypoint references recorded by the eTrex 10.
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Garmin eTrex 10
Here is a photo of the Garmin eTrex 10 hand held GPS unit and Anwenk Camera Strap Belt. The eTrex 10 came with the USB cable but the lanyard and carry case I purchased separately. The case is attached to the Anwenk Camera Strap Belt. It is a simple strap with plastic release buckles on the ends and elastic straps to secure the camera by the lens as shown below.
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After researching various hand held GPS units I decided on the Garmin eTrex 10. The price was affordable and the features were what I was looking for. Oddly enough my research turned up conflicting information on the map loaded on this device. The official view was that maps could not be uploaded to the device. However I found several instruction to uploading a topo map to the device. The device only has 8mb of memory and no way to expand on that. With this hike I found out that the memory was not going to be a problem. I uploaded a topo map (albeit the wrong one) to replace the base map on the device. The file was 2448 KB and covered 484 sq. miles. The map contained only one trail reference comprised of several trails joined together which was inaccurate but I did not need that feature anyway. The device recorded 6 miles of my trek in a track file of 231KB and 35 waypoints in a file of 6KB. This left 4.5 MB of unused memory on the device. In short the memory size was not an issue.
The device recorded the track using 1000 points of data consisting of time and date, latitude, longitude and elevation using both GPS and GLONASS satellites. It has a 2.2" monochrome display that was easy to read in bright sunlight. It also has geocaching features that I do not need so know nothing about. Elevation was off by various feet (averaged 30) but that is true with any handheld GPS in the mountains. My main purpose for this device was to upload a topo map and get my position on a paper map by comparing contour lines, marking my position (waypoints) whenever I took pictures or came to trail intersections and using track data to print out my hike as in the map on the bottom of this page. It was able to do all that and I am satisfied with my purchase and can recommend this unit.
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River Trail
River Trail follows the Jacob Fork River southeast to the Family Campground. It was deserted when I started my hike at 7:40 in the morning but when I finished my hike at around noon it was filled with families splashing away and people fishing. At one point I noticed trees on the bank with their roots exposed by erosion of the river when it rose due to heavy rainfall. The photos below show the interesting erosion effect.
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Raven Rock Trail
Raven Rock Trail begins at waypoint 5 for 1.4 miles where it meets with the Upper Falls Trail marked by waypoint 11. Climbing from waypoint 5, at 1300 feet, to waypoint 10, at 1840 feet, in approximately .9 miles in 90° weather was a chore but not as difficult as I had thought when I planned the trip. There were several places that had great views (see photo album) as shown in the photos below.
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Upper Falls Trail
I hiked 1.7 miles of the Upper Falls trail to the trailhead of HQ Trail. At one point I had to cross the Jacob Fork River just prior to entering the Upper Falls Campsites. The river was calm and shallow at this point and there were rocks piled across the river making the crossing easy and dry.
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Headquarters Trail
Headquarters Trail is 1.9 miles long and categorized as a strenuous trail due to the steep climbs along the trail. The path is wide enough for maintenance vehicles to transverse. In places the trail is strewn with rocks and very hard on your hiking boots and murder on street shoes.
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Data Comparison
Compare the two images in the picture to the left. The image on the bottom is scanned from the official topographical trail map of South Mountain Park provided by the North Carolina Division of Parks and Recreation. The image on the top is the scanned from the map below. Study the contour lines taking into consideration that in the upper image the intervals between contour lines is 20 feet whereas the bottom image intervals is 40 feet. The area between the contour lines measures the rise/fall in feet not the distance apart. A contour line that forms a circle is a peak. Lines that run parallel and close together indicates a cliff face or very steep mountain side depending on how close the lines are together.
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The yellow highlighted line on Map One is a trail marking. The darker line with the flags (waypoints) is the track as recorded by the eTrek 10. Although hard to read the waypoint on the far right is waypoint 20. The eTrex records this at elevation 2240 feet. Although not shown on Map Two, the contour line surrounding the peak on the far right with the trail crossing the top is recorded at 2200 feet. The contour line surrounding the peak on Map One is 2220 feet and the next one around that is 2200 feet. Our first summation using this data would tell us that the eTrex 10 is at least 20 feet off. However the scale of both maps did not allow for more contour lines to be drawn in and the peak does not level out at 2220 feet but rises further. Searching through the Photo Album we see that Pic37 to Pic40 was taken at Waypoint 20. I was standing close to the top of that peak when I took those pictures. Study Pic37 and Pic40 and you will notice that the picture is at a slight angle. This is due to trail still rising before it began to drop off on the other side of the peak. According to the GPSMapEdit software I am using to generate the map below Waypoint 20 is approximately 15 feet from the 2220 foot contour line.
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Data Comparison (cont)
Using the information above I can make the assumption that the accuracy of elevation on the eTrex 10 is within a 10-15 feet error margin. But what about longitude and latitude accuracy? Again using the GPSMapEdit software I clicked on Waypoint 20 and brought up the properties box shown in the picture to the left. GPSMapEdit displays the longitude and latitude at the position of the cursor (not shown but over Waypoint 20) on the status bar shown highlighted on the lower left of the picture. That is a difference of .0005 minutes in latitude.
In summary I would report that the accuracy of the data provided by the eTrex 10 is well above satisfactory and I am pleased with the performance of the unit.
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eTrex 10 Track/Waypoints Topo Map
The map to the left was generated by GPSMapEdit using track and waypoint GPX files from my eTrex 10 device and superimposed over a topo map downloaded from GPSFileDepot. The picture below is the altitude profile of the Raven Rock Trail.