Some one may have already discovered this, but I have not seen anything about it in the discussions. I have used Google Earth Pro for several years to digitize routes and depending on how close you put the camera to the terrain, digitizing this way can be quite accurate -- except -- how about that area that is totally obscured by trees and also how about the shift that occures from one satellite image set to another. It is best to determine which of the historic images are close enough together in space to allow switching from one to another if short sections are obscured. Then I discovered something else that is helpful.
If you get your topographic map images from the USGS site(s) typically you would download the .pdf version but then I saw that there is also a .kmz version -what is this? Well I found that you download the kmz version which is a zip file. Then unzip this and the resulting files will be kmz files, one or sometimes two. One of the two will load the map image over the earth image very accurately and you can digitize off that the part obscured by trees or other items. Now it is more accurate than guessing the route but not real accurate either so I limit my use of this to short distances. Currently I am digitizing the branches off the New River Sub. of CSX(C&O). I'll lay the track, and main roads and then put it in the unfinished section. /As recently as 20 years ago there were over a hundred loadouts (coal) in this area. Now, perhaps a dozen. I'm including the WV Secondary (former NS, now a short line) from across the river and just west of Handley to Cornelia which had an active loadout at the end. There is a currently active loadout off this line. NS also has a "paper railroad", the Vaugn RR, or VRR that extends a few more miles from the CSX Gauley Sub.. I am also including a number of branches that are actually abandoned, because of the operational issues they involved.
Also now that I know more about digitizing, and I have access to M-tracks, I plan to redo/reissue the Clinchfield routes.
Jerry Sullivan
If you get your topographic map images from the USGS site(s) typically you would download the .pdf version but then I saw that there is also a .kmz version -what is this? Well I found that you download the kmz version which is a zip file. Then unzip this and the resulting files will be kmz files, one or sometimes two. One of the two will load the map image over the earth image very accurately and you can digitize off that the part obscured by trees or other items. Now it is more accurate than guessing the route but not real accurate either so I limit my use of this to short distances. Currently I am digitizing the branches off the New River Sub. of CSX(C&O). I'll lay the track, and main roads and then put it in the unfinished section. /As recently as 20 years ago there were over a hundred loadouts (coal) in this area. Now, perhaps a dozen. I'm including the WV Secondary (former NS, now a short line) from across the river and just west of Handley to Cornelia which had an active loadout at the end. There is a currently active loadout off this line. NS also has a "paper railroad", the Vaugn RR, or VRR that extends a few more miles from the CSX Gauley Sub.. I am also including a number of branches that are actually abandoned, because of the operational issues they involved.
Also now that I know more about digitizing, and I have access to M-tracks, I plan to redo/reissue the Clinchfield routes.
Jerry Sullivan