diff --git a/ocrd_calamari/recognize.py b/ocrd_calamari/recognize.py
index a0eca4c..817d6d5 100644
--- a/ocrd_calamari/recognize.py
+++ b/ocrd_calamari/recognize.py
@@ -48,6 +48,14 @@ class CalamariRecognize(Processor):
         checkpoints = glob(self.parameter['checkpoint'])
         self.predictor = MultiPredictor(checkpoints=checkpoints)
 
+        self.network_input_channels = self.predictor.predictors[0].network.input_channels
+        #self.network_input_channels = self.predictor.predictors[0].network_params.channels # not used!
+        # binarization = self.predictor.predictors[0].model_params.data_preprocessor.binarization # not used!
+        # self.features = ('' if self.network_input_channels != 1 else
+        #                  'binarized' if binarization != 'GRAY' else
+        #                  'grayscale_normalized')
+        self.features = ''
+
         voter_params = VoterParams()
         voter_params.type = VoterParams.Type.Value(self.parameter['voter'].upper())
         self.voter = voter_from_proto(voter_params)
@@ -69,17 +77,27 @@ class CalamariRecognize(Processor):
             pcgts = page_from_file(self.workspace.download_file(input_file))
 
             page = pcgts.get_Page()
-            page_image, page_xywh, page_image_info = self.workspace.image_from_page(page, page_id)
+            page_image, page_coords, page_image_info = self.workspace.image_from_page(
+                page, page_id, feature_selector=self.features)
 
-            for region in pcgts.get_Page().get_TextRegion():
-                region_image, region_xywh = self.workspace.image_from_segment(region, page_image, page_xywh)
+            for region in page.get_TextRegion():
+                region_image, region_coords = self.workspace.image_from_segment(
+                    region, page_image, page_coords, feature_selector=self.features)
 
                 textlines = region.get_TextLine()
                 log.info("About to recognize %i lines of region '%s'", len(textlines), region.id)
-
                 line_images_np = []
-                for (line_no, line) in enumerate(textlines):
-                    line_image, line_coords = self.workspace.image_from_segment(line, region_image, region_xywh)
+                for line in textlines:
+                    log.debug("Recognizing line '%s' in region '%s'", line.id, region.id)
+
+                    line_image, line_coords = self.workspace.image_from_segment(line, region_image, region_coords, feature_selector=self.features)
+                    if ('binarized' not in line_coords['features'] and 'grayscale_normalized' not in line_coords['features'] and self.network_input_channels == 1):
+                        # We cannot use a feature selector for this since we don't
+                        # know whether the model expects (has been trained on)
+                        # binarized or grayscale images; but raw images are likely
+                        # always inadequate:
+                        log.warning("Using raw image for line '%s' in region '%s'", line.id, region.id)
+
                     line_image = line_image if all(line_image.size) else [[0]]
                     line_image_np = np.array(line_image, dtype=np.uint8)
                     line_images_np.append(line_image_np)
diff --git a/test/test_recognize.py b/test/test_recognize.py
index 0a1e558..fdb2679 100644
--- a/test/test_recognize.py
+++ b/test/test_recognize.py
@@ -6,12 +6,12 @@ from lxml import etree
 from glob import glob
 
 import pytest
+import logging
 from ocrd.resolver import Resolver
 
 from ocrd_calamari import CalamariRecognize
 from .base import assets
 
-
 METS_KANT = assets.url_of('kant_aufklaerung_1784-page-region-line-word_glyph/data/mets.xml')
 WORKSPACE_DIR = '/tmp/test-ocrd-calamari'
 CHECKPOINT_DIR = os.path.join(os.getcwd(), 'gt4histocr-calamari1')
@@ -99,6 +99,19 @@ def test_recognize_with_checkpoint_dir(workspace):
         assert "verſchuldeten" in f.read()
 
 
+def test_recognize_should_warn_if_given_rgb_image_and_single_channel_model(workspace, caplog):
+    caplog.set_level(logging.WARNING)
+    CalamariRecognize(
+        workspace,
+        input_file_grp="OCR-D-GT-SEG-LINE",
+        output_file_grp="OCR-D-OCR-CALAMARI-BROKEN",
+        parameter={'checkpoint': CHECKPOINT}
+    ).process()
+
+    interesting_log_messages = [t[2] for t in caplog.record_tuples if "Using raw image" in t[2]]
+    assert len(interesting_log_messages) > 10  # For every line!
+
+
 def test_word_segmentation(workspace):
     CalamariRecognize(
         workspace,