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JAKUB SISAK photography

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Jakub Sisak, GISP


May
9
comment Can a mask layer in advanced drawing options be easily reversed?
I added an example that explains it better. I need the exact opposite of what the masking layer can do. Something similar to the Data Frame "Clip to shape" option but for each layer rather then the entire Data Frame.
May
9
revised Can a mask layer in advanced drawing options be easily reversed?
added 500 characters in body
May
9
comment Can a mask layer in advanced drawing options be easily reversed?
I need a reverse of this: "If you pull a line layer below a polygon layer it will mask the line."
May
6
comment Can a mask layer in advanced drawing options be easily reversed?
Thanks Brad.Layer order won't work in this situation. lots of semi-transparent items, lots of complex layers. My line is behind a transparent relief, behind lakes and I need to continue the line as semi-transparent (different color, thickness for each symbol) above the lakes.
May
6
comment Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
Added link to the data to the post. (very bottom) link will expire in 7 days.
May
6
revised Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
added 101 characters in body
May
6
comment Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
I was able to sucessfuly create a "hydrologicaly correct" surface with the TopoToRaster tool by using the LiDAR points as point (spot) input. I created 2 surfaces with different output cell sizes: 2 and 4. Resulting Flow accumulation raster suffers from the same problems. I am beginning to suspect that this cannot be done in ArcGIS. I would also like to point out that it takes extremely long time to run the TopoToRaster.
May
6
revised Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
added 412 characters in body
May
6
asked Can a mask layer in advanced drawing options be easily reversed?
May
6
comment Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
When I multiply the input raster by 1000 I get the same results as before. I tried both the integer and the floating point. Resulting Flow Accumulation raster is nearly identical in both cases. Off to try to make the TopoToRaster technique work.
May
6
comment Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
And speaking of CDED I've had all kinds of issues (still unresolved) with the integer rounding and the resulting "terrace anomaly" issues.
May
6
comment Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
I actually tried this but the toold crashes a lot. I used the LiDAR derived contours (2K x 2K subset) then removed small insignificant contours to make the surface simpler and tried the TopoToRaster but it just keeps dying. (Too many points in the contour polyline error) Should I just try points elevations instead?
May
6
comment Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
Thanks Matt. Good stuff. I will try this and report back. Lots of very interesting information. Thanks for the effort you put into this.
May
5
awarded  Nice Question
May
5
revised Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
added 29 characters in body
May
5
comment Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
I have added further information to the post. Please see what results I get when I attempt to use a floating point DEM as input.
May
5
revised Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
added 674 characters in body; edited tags
May
5
revised Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
added 15 characters in body; edited tags
May
5
comment Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
Bill; the 1st (black) image is a Flow Accumulation raster produced from a Floating Point DEM input, the 2nd image is a Flow Accumulation raster produced from an Integer DEM input. (I edited the captions, Both have sinks filled) Can you elaborate on the flow direction raster needing to have its code values powers of 2? I just use the spatial analyst Flow Direction tool and use the output as is. (Right now the DEM I am using is 2K by 2K)
May
5
comment Methodology for creating accurate drainage networks (and catchments) from high resolution LiDAR DEM?
Jacques; what a relief. I am not crazy after all. Can you please make your comment an answer and provide more detail (source of that claim?) There is a paper by Xiaoye Liu and Zhenyu Zhang from the Monash University in Australia who were apparently able to use LiDAR for similar analysis. I tried to contact them by have not received an answer yet. onlinelibrary.wiley.com/doi/10.1111/j.1475-4762.2010.00955.x/…