Aerial Photos for route finding

[Papa Bear]

I have occasionally used the terraserver to investigate routes for potential bushwhacks (the shot in the link is of Owls Head, which I hope to be on next week). Advantages are the ability to switch back and forth between the topo map and the picture, various scales (zoom levels) etc. Place name finding is bad however. The big negative though is that the photos are old. The one of Owl's head is from 1994, and that's more recent than most. A lot can change in 10 or 15 years.

Question: do other folks look at these photos for scouting out routes, logging roads, etc.? Does anyone have other on-line sources other than the terraserver, especially more recent pictures?

Thanks
Pb

 

[el-bagr]

Question: do other folks look at these photos for scouting out routes, logging roads, etc.? Does anyone have other on-line sources other than the terraserver, especially more recent pictures?

yes -- I look at them
sometimes -- almost all of the states now have free aerial photo GIS data layers; sometimes these are more recent than terraserver-usa. Data of this type is often called "DOQ" (Digital Ortho Quads).

See, e.g., Maine's APOLLO system.

 

[WalksWithBlackflies]

This is a good source for historical topos which identify old logging roads and trails:

http://docs.unh.edu/nhtopos/nhtopos.htm

Some areas go back further than others.

 

[CaptCaper]

I have full coverage of the White Mountain National Forest with arials,and color satillite shots I use. And can be made to show in 3D.Sometimes one will show better than the other.
They are part of the Topo 5.0 from DeLorme. Also in the packet comes USGS Quad maps.

 

[^MtnMike^]

I don't bushwack, but I have been using USGS DEM data to generate 3D terrain models that can be matched to Topo maps and manipulated in various ways through modeling and graphic design software. It's a good way to visualize the terrain. And the resolution is up to 10 meters, quite good even if not perfect. Useful for planning and fun to play around with.

Examples HERE and HERE

The DEM's, along with DLG's, DRG's, and other USGS geographical data is available from GeoComm among other places.
^MtnMike^

 

[peakbagger]

If you want the latest orthophotos for NH check out the UNH granit website. They have the entire state available to download but be aware that the files are huge (definitely not much use for a dial up connection). UNH also will sell you a CD by county if you arent in the mood to download (if I remember correctly te CD's are quite reasonable.

They are broken up by county and someone has made sure that the best and most recent image available is used. The photos are stoted in Mr Sid format which requires a free viewer which you need to track down on the web. I beleive that Arc cad reads the files directly. One downside is that with the free viewer you cant stich together photos. I usually export them in raster and stitch them with autocad. I believe the Maine GIS website also has these photos but I seem to remember they are not as easy to download. They are all stored in the USGS format so it may be worth picking up the USGS map index books which explain the system.

To get anything newer, you will probably need to pay a private source. I have bought newer images from the federal government (USGS- Eros data center but its not very fast or free). The local cooperative extension office has quite a collection that you can view (but not take home).

 

[mavs00]

I don't bushwack, but I have been using USGS DEM data to generate 3D terrain models that can be matched to Topo maps and manipulated in various ways through modeling and graphic design software. It's a good way to visualize the terrain. And the resolution is up to 10 meters, quite good even if not perfect. Useful for planning and fun to play around with.

Examples HERE and HERE

The DEM's, along with DLG's, DRG's, and other USGS geographical data is available from GeoComm among other places.
^MtnMike^

Mike,

That's pretty interesting stuff, I'd be interesting in doing some 3D rendering. What software are you using and what is the process for rendering the terrain. Thanks

 

[^MtnMike^]

Mike,

That's pretty interesting stuff, I'd be interesting in doing some 3D rendering. What software are you using and what is the process for rendering the terrain. Thanks [/B]

Thanks,

Right now I'm using a couple of different applications.
The first is a great program called Global Mapper. I use this application to load and convert the DEM quadrangles. Global mapper reads the new SDTS format as well as a host of other USGS formats. GM allows you to load multiple quadrangles at once. The program even lines them up for you and allows you to select and export only the areas on a quad (or quads) you need which is handy if you need an area that stradles two or more quads.
The program can export to many popular 3D and 2D formats. It can also handle many of the other USGS formats. I'm using an older version of the application which sells for less than the current version. They also have a free version you can download to try out, but you can't export anything with it.

After I lay out the quads I export the data to the stereolithograph (STL) format. I also export the DRG topo data that corresponds to the DEM data. This I export as a BMP image file.

From there I import the data into a second program called 3D Studio Max. Using the BMP image generated with Global Mapper I texture map the 3D mesh and render it using the program's built in rendering engine. 3D Studio is a great program but it's a bit expensive and a bit of overkill for something like this. I just use it because I have it for other work I do.
Any 3D design program should be able to perform the same task though, even some of the freeware ones available. Some may even be better suited for this type of work. There is one out there called MircoDEM (I think) that can render 3D LOS views from any point on the mesh.

That's the quick explaination, I wasn't sure how much detail you wanted. I can elaborate if necessary.

^MtnMike^

 

[Tramper Al]

Canoe routes

Yes, I use aerial photos for route planning, particularly for canoe routes.

I can often pinpoint the location of rapids, and scout possible portage routes along rough roads or paths visible from the air. I have chosen my takeout parking spot by first seeing it on the aerial photos. I have found this to be very helpful.