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I am using ArcMap 10.8

I have multiple digitized historic General Land Office (GLO) maps (JP2 rasters) that I am georeferencing. Each one aligns with a single rectangular feature within an existing Township/Range polygon shapefile, but the historic maps have margins that extend beyond each polygon feature (see image on the left below). I want to remove the margins so that the maps don’t overlap after being georeferenced (see image on the right below).

Can I clip the georeferenced rasters in ArcMap (10.8) all at once so that each raster is clipped to a specific feature within the same shapefile?

Left: historic maps with overlapping margins. Red lines show polygon grid to be used for clip; Right: desired result of historic maps clipped to grid to remove margins.

Left: historic maps with overlapping margins. Red lines show the Township/Range grid to be used for clip; Right: desired result of historic maps clipped to grid to remove margins.

Edit: In response to @Hornbydd : Each cell feature in the polygon grid has a unique ID attribute (PLSSID) that matches the name of each associated raster. I made the model using Iterate Feature Selection to run through each polygon feature based on this unique PLSSID attribute. How do I make it run through multiple rasters as the input if I already have an iterator in the model to run through each polygon feature?

Here is the model so far:

enter image description here

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    You use inline variable substitution to construct the in raster path, e.g. c:\myrasterfolder\%value%_anyothertext.tiff. you would do the same for the output clip.
    – Hornbydd
    Jul 29, 2021 at 8:03

2 Answers 2

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You need to have the raster name match the grid cell so you can match the geometry with the raster. For example top left raster is called r1 so the cell needs to be tagged with r1, top right is r2 so the cell is tagged with r2 and so on.

Then a simple model iterating over the cell values will allow you to identify the raster and run it through the clip tool.

This assumes you have already done the georeferencing.

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  • I edited my question to include the unsuccessful model I tried and a follow up question
    – Emily R.
    Jul 28, 2021 at 22:38
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I am posting my successful model thanks to the help of @Hornbydd.

Each cell feature in the polygon grid has a unique ID attribute (PLSSID) that matches the name of each associated raster. I made a model using Iterate Feature Selection to run through each polygon feature based on this unique PLSSID attribute. The output feature becomes the clipping extent in the clip tool. For the input raster in the clip tool, I used inline variable substitution (c:\rasterfolder\ %value%.jp2) to allow the model to grab the raster that matches the polygon feature on each iteration. For the output, I also used inline variable substitution (c:\rasterfolder\clip_%value%.jp2) so that the output raster name matches the input name with, the word "clip" added in front of it.

EDIT: I had to clip my polygon grid to remove any features that I don't have a matching raster for, otherwise the tool doesn't work. All of the features in the polygon grid had to have an associated raster or else the model failed trying to find raster files that don't exist. If there is a way to run this model without clipping the polygon shapefile file first (i.e. to make it ignore features with no associated raster file), I don't know how to do it.

For people new to iterators in Model Builder like myself, I recommend this video: https://youtu.be/SDlfwZVNz_g

enter image description here

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