How to change the symbology on many image files within a group?

Question

I have a group of raster images from lidar data (so a DEM). When loaded in, they all have different symbology - so their color scheme and color ramp are all different. I would like to create a group with images that all have the same symbology, so that I can visually compare topography between the adjacent images. There are approximately 600 images within this group, so I don't want to change the color scheme for each image individually.

I've tried changing the symbology of one image, and using the "apply symbology to layer" function, but this does not work because it seems my layer or group of images is not considered a raster layer... I also tried first making this layer a raster layer with "make raster layer", but the layer or group that I have is not considered a valid type of input.

I'm using arcmap 10.0. Any advice or suggestions on how to do this would be most helpful.

Answer 1

I think your layers display differently because the statistics are different, your stretches min-max, standard deviations or percent clip are based on raster statistics. You will need to decide on a valid range to cover all your data and override the existing statistics.

You should be able to modify the source layer statistics from the layer dialog and use From custom settings (below), then when replicating the symbology using Apply Symbology from Layer and hopefully the manual statistics will come with it.

If replicating the symbology does not copy the enforced statistics the tool Set Raster Properties can be used to override valid existing statistics or create new statistics from an XML file. Previously I have resampled and mosaiced the reduced resolution rasters and then enforced the statistics from that dataset onto the tiles - that works. If that is not an option you will need to edit a statistics file file manually, save as XML from the custom settings:

<?xml version="1.0"?>
<RasterStatistics xml:lang="en"><Band><min>136.600646972656</min><max>138.838562011719</max><mean>136.952300882018</mean><stddev>0.263399915380974</stddev></Band></RasterStatistics>

Modify the minimum, maximum, mean... and then supply this XML file to the tool to override the existing statistics. If you don't want to edit an XML file you could provide the parameters to the tool but I have no example of parameter update.