diff --git a/src/lib/OpenEXRUtil/ImfCheckFile.cpp b/src/lib/OpenEXRUtil/ImfCheckFile.cpp
index 4d45dad69f..202ca0d2d0 100644
--- a/src/lib/OpenEXRUtil/ImfCheckFile.cpp
+++ b/src/lib/OpenEXRUtil/ImfCheckFile.cpp
@@ -1247,7 +1247,7 @@ realloc_deepdata(exr_decode_pipeline_t* decode)
         bytes += totsamps * outc.user_bytes_per_element;
     }
 
-    if (bytes >= gMaxBytesPerDeepScanline * h)
+    if (bytes >= gMaxBytesPerDeepScanline)
     {
         for (int c = 0; c < decode->channel_count; c++)
         {
@@ -1332,6 +1332,8 @@ readCoreScanlinePart (
             }
 
             doread = true;
+            if (reduceMemory && bytes >= gMaxBytesPerScanline)
+                doread = false;
 
             if (cinfo.type == EXR_STORAGE_DEEP_SCANLINE)
             {
@@ -1340,8 +1342,6 @@ readCoreScanlinePart (
             }
             else
             {
-                if (reduceMemory && bytes >= gMaxBytesPerScanline) doread = false;
-
                 if (doread) imgdata.resize (bytes);
             }
             rv = exr_decoding_choose_default_routines (f, part, &decoder);
@@ -1507,6 +1507,9 @@ readCoreTiledPart (
                         }
 
                         doread = true;
+                        if (reduceMemory && bytes >= gMaxTileBytes)
+                            doread = false;
+
                         if (cinfo.type == EXR_STORAGE_DEEP_TILED)
                         {
                             decoder.decoding_user_data       = &tiledata;
@@ -1514,9 +1517,6 @@ readCoreTiledPart (
                         }
                         else
                         {
-                            if (reduceMemory && bytes >= gMaxTileBytes)
-                                doread = false;
-
                             if (doread) tiledata.resize (bytes);
                         }
                         rv = exr_decoding_choose_default_routines (
@@ -1647,6 +1647,20 @@ runCoreChecks (const char* filename, bool reduceMemory, bool reduceTime)
 
     cinit.error_handler_fn = &core_error_handler_cb;
 
+    if (reduceMemory || reduceTime)
+    {
+        /* could use set_default functions for this, but those just
+         * initialize the context, doing it in the initializer is mt
+         * safe...
+         * exr_set_default_maximum_image_size (2048, 2048);
+         * exr_set_default_maximum_tile_size (512, 512);
+         */
+        cinit.max_image_width = 2048;
+        cinit.max_image_height = 2048;
+        cinit.max_tile_width = 512;
+        cinit.max_tile_height = 512;
+    }
+
     rv = exr_start_read (&f, filename, &cinit);
     if (rv != EXR_ERR_SUCCESS) return true;