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I want to quantify how much land individual point features can "see" using the Viewshed tool. I can generate a complete/universal raster surface, but not one that itemizes the number of cells visible per each individual point feature. I know that I can do this by selecting individual points and then run Viewshed, but given the number of points that I wish to calculate, this would be extremely time consuming.

Does anyone know a way that I can calculate how much land can be seen (cell counts are fine) for individual point features without having to run the calculation individually on every point in a database. I was hoping for an output table with each point feature listed, followed by the number of visible cells (for the point feature). Perhaps a different tool??

Thanks in advance

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    I think you are going to be stuck with running Viewshed per point. The visible area process (extracting cell count, or even an areal measurement) can be scripted and/or assembled in ModelBuilder, which saves you the trouble of manually executing the tool yourself -- but the Viewshed process will still need to run. If you're instead interested in a number of limited targets (e.g. "how many windmills can I see from each vantage point" or a similar question), it could be done with sight lines. – Erica Jul 1 '14 at 16:14
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    What if you used Observer Points (OP), converted the output to vector in a file geodatabase (so you get area calculated - might have to project to local coordinate system), and summarized on the attributes that the OP tool created? Seems that would work just fine... OP creates a detailed attribute table that gives you all combinations of input points and the areas that are visible to them. – DPSSpatial Jul 1 '14 at 16:40
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    unfortunately, I get an error of too many point trying the OP way. I actually have several hundred points to do and the OP methods says a max of 16. – matt Jul 1 '14 at 17:05
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    As the other comments suggest, there is no single tool what will do what you want with all of your data at once. Incorporating either viewshed or observer points into a script or model is the solution. Viewshed would do one at a time while observer points could do up to 16 at a time. You'd then need to combine or summarize the results, either in the model or as a separate process after. This question would be a good place to start. – Chris W Jul 1 '14 at 20:56
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I think you are going to be stuck with running Viewshed per point, unfortunately. Since the area-visible changes for each unique point's perspective, it needs to be calculated for each unique point. The visible area process (extracting cell count, or even an areal measurement) can be scripted and/or assembled in ModelBuilder, which saves you the trouble of manually executing the tool yourself -- but the Viewshed process will still need to run. (Alternatively, as noted by mapBaker and Chris W in comments to the original Question, run Observer Points repeatedly in a script or model.)

If you're instead interested in a number of limited targets (e.g. "how many windmills can I see from each vantage point" or a similar question), it could be done with sight lines.

(You could, in theory, convert the raster to a bunch of points, run Viewshed once using all those points as the "observers," and get one raster that represents the visible area (if n points can see a location, then that location can see n points, which can be converted to an areal amount). While this is a simpler approach because you just run Viewshed once, it will take much, much longer to execute since the tool is actually calculating the Viewshed of every single point on the raster individually -- just like you scripted above. I do not recommend this method.)

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