diff --git a/doc/sphinx-guides/source/api/dataaccess.rst b/doc/sphinx-guides/source/api/dataaccess.rst
index 3a91dca5024..b6a8b3ff3f0 100755
--- a/doc/sphinx-guides/source/api/dataaccess.rst
+++ b/doc/sphinx-guides/source/api/dataaccess.rst
@@ -58,8 +58,8 @@ the following parameter values are supported (for image and pdf files only):
 ==============  ===========
 Value           Description
 ==============  ===========
-true            Generates a thumbnail image, by rescaling to the default thumbnail size (64 pixels)
-``N``           Rescales the image to ``N`` pixels.
+true            Generates a thumbnail image by rescaling to the default thumbnail size (64 pixels wide).
+``N``           Rescales the image to ``N`` pixels wide. ``imageThumb=true`` and ``imageThumb=64`` are equivalent.
 ==============  ===========
 
 Multiple File ("bundle") download
diff --git a/src/test/java/edu/harvard/iq/dataverse/api/SearchIT.java b/src/test/java/edu/harvard/iq/dataverse/api/SearchIT.java
index 7a29506008a..1788d3fd1fc 100644
--- a/src/test/java/edu/harvard/iq/dataverse/api/SearchIT.java
+++ b/src/test/java/edu/harvard/iq/dataverse/api/SearchIT.java
@@ -384,11 +384,25 @@ public void testDatasetThumbnail() {
 
         
         Response getThumbnailImageA = UtilIT.getDatasetThumbnail(datasetPersistentId, apiToken); //
-        getThumbnailImageA.prettyPrint();
         getThumbnailImageA.then().assertThat()
                 .contentType("image/png")
                 .statusCode(OK.getStatusCode());
 
+        // heads up that calling prettyPrint on an image will increase the length.
+        assertEquals(1153, getThumbnailImageA.asByteArray().length);
+
+        // A width of "true" is 1893 bytes. 64 pixels wide is the default.
+        // A width of "500" is 11372 bytes. 500 pixels wide.
+        String trueOrWidthInPixels = "true";
+//        String trueOrWidthInPixels = "500";
+        Response getFileThumbnailImageA = UtilIT.getFileThumbnail(dataFileId1.toString(), trueOrWidthInPixels, apiToken);
+        getFileThumbnailImageA.then().assertThat()
+                .contentType("image/png")
+                .statusCode(OK.getStatusCode());
+
+        // heads up that calling prettyPrint on an image will increase the length.
+        assertEquals(1893, getFileThumbnailImageA.asByteArray().length);
+
         InputStream inputStream2creator = UtilIT.getInputStreamFromUnirest(thumbnailUrl, apiToken);
         assertEquals(treesAsBase64, UtilIT.inputStreamToDataUrlSchemeBase64Png(inputStream2creator));
 
@@ -407,7 +421,6 @@ public void testDatasetThumbnail() {
         }
 
         Response getThumbnailImage2 = UtilIT.getDatasetThumbnail(datasetPersistentId, apiToken);
-        getThumbnailImage2.prettyPrint();
         getThumbnailImage2.then().assertThat()
                 //                .body(CoreMatchers.equalTo(decodedImg))
                 .contentType("image/png")
@@ -419,6 +432,9 @@ public void testDatasetThumbnail() {
                 //                .content(CoreMatchers.equalTo(decodedImg))
                 .statusCode(200);
 
+        // heads up that calling prettyPrint on an image will increase the length.
+        assertEquals(1153, getThumbnailImage2.asByteArray().length);
+
         String pathToFile = "src/main/webapp/resources/images/dataverseproject.png";
         Response uploadSecondImage = UtilIT.uploadFileViaNative(datasetId.toString(), pathToFile, apiToken);
         uploadSecondImage.prettyPrint();
@@ -594,11 +610,13 @@ public void testDatasetThumbnail() {
                 .statusCode(200);
 
         Response getThumbnailImageNoSpecialAccess99 = UtilIT.getDatasetThumbnail(datasetPersistentId, noSpecialAcessApiToken);
-//        getThumbnailImageNoSpecialAccess99.prettyPrint();
         getThumbnailImageNoSpecialAccess99.then().assertThat()
                 .contentType("image/png")
                 .statusCode(OK.getStatusCode());
 
+        // heads up that calling prettyPrint on an image will increase the length.
+        assertEquals(1153, getThumbnailImage2.asByteArray().length);
+
         InputStream inputStream99creator = UtilIT.getInputStreamFromUnirest(thumbnailUrl, apiToken);
         assertEquals(treesAsBase64, UtilIT.inputStreamToDataUrlSchemeBase64Png(inputStream99creator));
 
diff --git a/src/test/java/edu/harvard/iq/dataverse/api/UtilIT.java b/src/test/java/edu/harvard/iq/dataverse/api/UtilIT.java
index 61b5f64d575..5f485e40212 100644
--- a/src/test/java/edu/harvard/iq/dataverse/api/UtilIT.java
+++ b/src/test/java/edu/harvard/iq/dataverse/api/UtilIT.java
@@ -1231,6 +1231,15 @@ static Response getDatasetThumbnailMetadata(Integer datasetId, String apiToken)
                 .get("/api/admin/datasets/thumbnailMetadata/" + datasetId);
     }
 
+    /**
+     * @param trueOrWidthInPixels Passing "true" will result in the default width in pixels (64).
+     */
+    static Response getFileThumbnail(String fileDatabaseId, String trueOrWidthInPixels, String apiToken) {
+        return given()
+                .header(API_TOKEN_HTTP_HEADER, apiToken)
+                .get("/api/access/datafile/" + fileDatabaseId + "?imageThumb=" + trueOrWidthInPixels);
+    }
+
     static Response useThumbnailFromDataFile(String datasetPersistentId, long dataFileId1, String apiToken) {
         return given()
                 .header(API_TOKEN_HTTP_HEADER, apiToken)