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Discussion: Looks quite nice - except f...

in: PG; PG > 2011-10-17

Oct 17, 2011 9:32 PM # 
Looks quite nice - except for that bit on Bare Mtn....
Oct 17, 2011 11:29 PM # 
These MA areas look like great practice for Switzerland. How long do you think is "longer than you think?" ;)
Oct 17, 2011 11:38 PM # 
The original plan was to finish the field work this fall. Whether that happens depends on the weather in November/December and how soon snow comes.

Lots of hills, and the north slope isn't rocky underfoot except right at the top.
Oct 17, 2011 11:40 PM # 
Clint -- Eddie was just having fun, adding a little to the south edge and seeing how many cliffs he could spot. It's a nice view of the start and finish of the Seven Sisters.
Oct 19, 2011 12:55 AM # 
Is Eddie getting the fences (around the open area) from the lidar? Is he also getting the differences between rock outcrops on earth banks?
Oct 19, 2011 1:20 AM # 
All I know is so far I've been very pleased. If he could have picked up all the bike trails that would have been wonderful (he got bits). He has gotten as far as I've seen all the old woods roads that leave a wider impression even if nothing is visible from an aerial photo.
Oct 19, 2011 4:18 AM # 
All the fences there came from an Amherst GIS vector dataset. I may have added one or two near houses that were visible in the photos. I also deleted a bunch of obvious misidentified fence segments in that vector set (sometimes bits of fence turned out to be cars in the aerial photos). So its likely some automated algorithm was used for the fences. Sometimes you can see fences in lidar in open areas, just like power lines, but they weren't visible in this data. In this case, the fences are visible in the orthophoto

Same deal with the buildings - the ones on the east half of the map were from Amherst GIS. They are a little ragged. I added the ones on the west side manually from lidar and photos.

I can't tell the difference between earth bank and cliff in the lidar. I make a guess as to which is which based on context and sometimes simply to make it clearer (the brown earth bank symbol can get lost in the contours). Its up to the fieldchecker to make the final decision. They should all really be "generic steep ground thingy" symbol. The one thing that is correct is the facing direction - that you can tell from the lidar, not only from the contours, but the signature in the filtered bare earth is bright-over-dark. Sometimes cliffs don't face directly down the fall line.
Oct 19, 2011 4:58 AM # 
The area just south of the paved area at the east end of Chmura rd. looks alot like an old ski hill. And indeed it was. Tinker Hill. Thanks to NELSAP for the info. Maybe we should send them a snippet of the basemap and lidar for their records.
Oct 19, 2011 5:25 AM # 
Shaded relief of lidar bare earth surface facing the ski area (facing SSE):
Oct 19, 2011 1:24 PM # 
I sent NELSAP some info on a ski area in Worcester about six months ago, but it hasn't showed up on the site yet.
Oct 20, 2011 1:26 AM # 
Talk about getting all VT overflown with LIDAR by Dec this year. Stay tuned, may be better mapping around the house.
Oct 20, 2011 2:04 AM # 
Thanks Eddie.
Oct 20, 2011 5:17 PM # 
Wow, cool!! PG, are you going to assign us mapping homework? =)

This discussion thread is closed.