Discussion: Two Pullauta questions
in: Jagge
Oct 25, 2016 2:10 PM
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Hey!
I had two questions related to Pullauta and I was wondering what your thoughts were.
First question:
I'm having trouble with data from my state, Pennsylvania. It often comes out with WAY too many cliffs. I've changed the cliff classification to very high values (4 and 10) and the number of cliffs fortunately decreases, but then the real cliffs aren't represented. The links below are some maps I've generated that have had this problem.
Do you have any idea what could be causing it?
Neversink Mountain:
https://goo.gl/photos/ZQzuDJoJMBW1Kxx36
Berk County Park:
https://goo.gl/photos/2hvHz8kJUUyTfcYJ8
And second question:
The maps I've made so far are not representing accurately a type of bush that is common to central Spain called Cistus ladanifer. It often grows quite thick in open areas and is represented by mappers as green slash. But the pullauta maps I've made usually represent with areas filled with cistus ladanifer as open fields.
Do you think it could be a problem with the point classification? So far, I classify the points as follows: Ground <0.5m, low veg 0.5-2m, mid veg 2-5m, and high veg >5m.
Or perhaps I should change how I classify the veg in the pullauta ini file and test different configurations of that?
Thanks for any pointers you have time for!
I had two questions related to Pullauta and I was wondering what your thoughts were.
First question:
I'm having trouble with data from my state, Pennsylvania. It often comes out with WAY too many cliffs. I've changed the cliff classification to very high values (4 and 10) and the number of cliffs fortunately decreases, but then the real cliffs aren't represented. The links below are some maps I've generated that have had this problem.
Do you have any idea what could be causing it?
Neversink Mountain:
https://goo.gl/photos/ZQzuDJoJMBW1Kxx36
Berk County Park:
https://goo.gl/photos/2hvHz8kJUUyTfcYJ8
And second question:
The maps I've made so far are not representing accurately a type of bush that is common to central Spain called Cistus ladanifer. It often grows quite thick in open areas and is represented by mappers as green slash. But the pullauta maps I've made usually represent with areas filled with cistus ladanifer as open fields.
Do you think it could be a problem with the point classification? So far, I classify the points as follows: Ground <0.5m, low veg 0.5-2m, mid veg 2-5m, and high veg >5m.
Or perhaps I should change how I classify the veg in the pullauta ini file and test different configurations of that?
Thanks for any pointers you have time for!
Oct 25, 2016 3:48 PM
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About cliffs. Are contours correct? Or is elevation in lidar files in feet istead of meters. That might make small drops be seen as cliffs, but hen you would also get about 1.5 m contour interval instead of 5m. If thats the problem, convert feet to meters.
Seconfd possibpbility is you have two datasets overlapping here and those are ground classified separately. So courd level was seen slightly differetly making it look spikey when coulds are combined. What you need to do is drop the other one or even better, ground classify it again by yourself. you can take a look for example at lastools lasground. https://rapidlasso.com/2015/08/07/use-buffers-when...
I have got similar cliffs couple of times (once at Alaska and once somewhere else) and ended up re-ground classifying it all to get something sensible out of it.
Then vegetation. Pullatuin does not use low veg mid veg etc classificatiuons. So you need to set the height values you want to see as green or green stripes (pullautin does stripes too these days) to the ini file.
Seconfd possibpbility is you have two datasets overlapping here and those are ground classified separately. So courd level was seen slightly differetly making it look spikey when coulds are combined. What you need to do is drop the other one or even better, ground classify it again by yourself. you can take a look for example at lastools lasground. https://rapidlasso.com/2015/08/07/use-buffers-when...
I have got similar cliffs couple of times (once at Alaska and once somewhere else) and ended up re-ground classifying it all to get something sensible out of it.
Then vegetation. Pullatuin does not use low veg mid veg etc classificatiuons. So you need to set the height values you want to see as green or green stripes (pullautin does stripes too these days) to the ini file.
Oct 27, 2016 9:00 PM
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I was pretty certain I had converted the contours to meters. It wasn't letting me generate them before conversion. I tried the ground classification and it produced the same results. It's completely possible that I've done it wrong. So, I'll keep playing around with it and let you know what happens. Thanks, man!
This discussion thread is closed.