What is z-factor in Hillshade?
The Z-Factor parameter is in many Spatial Analyst and 3D Analyst tools; Hillshade and Slope are the two that I use most. Not setting the Z-Factor correctly makes the hillshades look heavy or leaden. It will also make slope values, e.g., for percent slope very small, like 0.00023% – 0.00032% instead of 1.8% to 7.2%.
What do Hillshade values represent?
The output values can range from 0 to 255, with 0 representing the darkest areas, and 255 the brightest. This is the default. SHADOWS—The output shaded raster considers both local illumination angles and shadows. The output values range from 0 to 255, with 0 representing the shadow areas, and 255 the brightest.
What is z-factor in slope ArcGIS?
The z-factor is a conversion factor that adjusts the units of measure for the vertical (or elevation) units when they are different from the horizontal coordinate (x,y) units of the input surface. It is the number of ground x,y units in one surface z-unit.
What does a Hillshade map show?
Hillshading is a technique for creating relief maps, showing the topographical shape of hills and mountains using shading (levels of gray) on a map, just to indicate relative slopes, mountain ridges, not absolute height.
What is Hillshade in ArcGIS?
Overview. The hillshade function produces a grayscale 3D representation of the terrain surface, with the sun’s relative position taken into account for shading the image. Hillshading is a technique for visualizing terrain determined by a light source and the slope and aspect of the elevation surface.
How do I calculate Z-factor?
Z factor is calculated as the separation band divided by the dynamic range (i.e., the difference between the sample mean and the control mean), which is calculated as shown in Equation 1. The same equation can be expressed in Equation 2 when rearranged. Based on Z-factor value, the hits can be discerned.
How do you calculate Z-factor?
Compressibility factor, usually defined as Z = pV/RT, is unity for an ideal gas.
What is the Z-factor in statistics?
The Z-factor is a measure of statistical effect size. It has been proposed for use in high-throughput screening (where it is also known as Z-prime), and commonly written as Z’ to judge whether the response in a particular assay is large enough to warrant further attention.
What does Z-factor tell you?
The Z’ (Z-prime) statistic is widely used as a measure of assay quality, showing the separation between the distributions of the positive and negative controls. The Z′-factor describes how well separated the positive and negative controls are, and indicates likelihood of false positives or negatives.
What are the appropriate Z-factors for a hillshaded surface?
If your x,y units are decimal degrees and your z units are meters, some appropriate z-factors for particular latitudes are: You can create dramatic three-dimensional views of the hillshaded surface by draping the output raster using ArcGIS ArcScene. When the input raster needs to be resampled, the Bilinear technique will be used.
What are the appropriate Z-factors for particular latitudes in ArcGIS?
If your x,y units are decimal degrees and your z units are meters, some appropriate z-factors for particular latitudes are: You can create dramatic three-dimensional views of the hillshaded surface by draping the output raster using ArcGIS ArcScene.
Why is there a hillshade on my map?
If the input raster is in a spherical coordinate system, such as decimal degrees, the resulting hillshade may look peculiar. This is due to the difference in measure between the horizontal ground units and the elevation z units.
What are the parameters of the hillshade function?
The Hillshade function has the following parameters: The input elevation dataset. Traditional —Calculates hillshade from a single illumination direction. You can set the Azimuth and Altitude options to control the location of the light source.