![]() ![]() The good news is, they’ve dropped the price - it used to be $1 per square kilometer - and, they give you $100 worth for free (400 sq. ![]() km., so the cost would be $38.75 per quad! Holy mother of bankruptcies I can’t afford to be a map junky at that rate! The average USGS 7.5′ topo quad covers around 155 sq. That may not sound like much, but let’s do the math. You download it from DeLorme at $0.25 per square kilometer. Unfortunately, the aerial imagery comes at quite a cost. Further down this page are additional screenshots, including one showing color Sat 10 imagery (the section missing is an area that I did not download for transfer to the PN-20). To the left is a screenshot that utilizes vector files generated from Topo USA 6.0. Beside it, to the right is a screenshot showing a 1:24,000 scale USGS topo map. Meter/pixel, 4 meters/pixel, 16 meters/pixel and 64 meters/pixel.ĭeLorme appears to be utilizing the one meter/pixel imagery.Ĭompare prices on the DeLorme Earthmate GPS PN-20īelow to the left is an aerial photo screenshot, showing a logging road / trail in dense redwoods. ![]() Supplied by USGS which are available at multiple resolutions – 1 Aerial photos and USGS topo maps, on the other hand, will onlyĪppear clear at one zoom level. Vector lines are redrawn, and therefore appear sharp, at every zoom For a more detailed explanation of raster versus vector imagery, see What kind of maps can I put on my GPS (and what do you mean by raster and vector)? ![]() The technical term is raster imagery, and they eat up much more memory than vector files. The DeLorme PN-20 differs in that it can also accommodate images, such as aerial photos and USGS topo maps. Most GPS receivers utilize vector files - basically data files consisting of lines and points. Before we get into the details, let’s get up to speed on aerial photos, and why other GPS receivers lack this capability.Īerial photos on the DeLorme Earthmate PN-20 Having said that, DeLorme clearly has some improvements they need to make, and I hope they do, because this is one nifty device. It is incredibly cool to be carrying a GPS that shows your position on an aerial photo. The DeLorme Earthmate GPS PN-20 does just that, and displays USGS topo maps too. UPDATE: There are now two newer models in this series, the DeLorme PN-30 and PN-40.įinally, a GPS that displays aerial photos. Hands on with the DeLorme Earthmate PN-20 ![]()
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