diff --git a/Makefile b/Makefile
index 539d992..cabe4e1 100644
--- a/Makefile
+++ b/Makefile
@@ -98,6 +98,8 @@ example-preprocess:
 		--base-dir . \
 		--dataset-field datasets.train \
 		--config config.yaml \
+		--force \
+		-vv \
 		config.yaml example_data/preprocessed
 
 example-train:
diff --git a/src/batdetect2/cli/preprocess.py b/src/batdetect2/cli/preprocess.py
index 15a7681..0ab537c 100644
--- a/src/batdetect2/cli/preprocess.py
+++ b/src/batdetect2/cli/preprocess.py
@@ -1,7 +1,9 @@
+import sys
 from pathlib import Path
 from typing import Optional
 
 import click
+import yaml
 from loguru import logger
 
 from batdetect2.cli.base import cli
@@ -83,6 +85,12 @@ __all__ = ["preprocess"]
         "the program will use all available cores."
     ),
 )
+@click.option(
+    "-v",
+    "--verbose",
+    count=True,
+    help="Increase verbosity. -v for INFO, -vv for DEBUG.",
+)
 def preprocess(
     dataset_config: Path,
     output: Path,
@@ -92,7 +100,17 @@ def preprocess(
     force: bool = False,
     num_workers: Optional[int] = None,
     dataset_field: Optional[str] = None,
+    verbose: int = 0,
 ):
+    logger.remove()
+    if verbose == 0:
+        log_level = "WARNING"
+    elif verbose == 1:
+        log_level = "INFO"
+    else:
+        log_level = "DEBUG"
+    logger.add(sys.stderr, level=log_level)
+
     logger.info("Starting preprocessing.")
 
     output = Path(output)
@@ -101,11 +119,20 @@ def preprocess(
     base_dir = base_dir or Path.cwd()
     logger.debug("Current working directory: {base_dir}", base_dir=base_dir)
 
+    if config:
+        logger.info(
+            "Loading preprocessing config from: {config}", config=config
+        )
+
     conf = (
         load_train_preprocessing_config(config, field=config_field)
         if config is not None
         else TrainPreprocessConfig()
     )
+    logger.debug(
+        "Preprocessing config:\n{conf}",
+        conf=yaml.dump(conf.model_dump()),
+    )
 
     dataset = load_dataset_from_config(
         dataset_config,
diff --git a/src/batdetect2/configs.py b/src/batdetect2/configs.py
index 43764f5..e4908bf 100644
--- a/src/batdetect2/configs.py
+++ b/src/batdetect2/configs.py
@@ -38,7 +38,7 @@ class BaseConfig(BaseModel):
         Pydantic model configuration dictionary. Set to forbid extra fields.
     """
 
-    model_config = ConfigDict(extra="allow")
+    model_config = ConfigDict(extra="ignore")
 
 
 T = TypeVar("T", bound=BaseModel)
diff --git a/src/batdetect2/train/preprocess.py b/src/batdetect2/train/preprocess.py
index 11c9972..a6f4f92 100644
--- a/src/batdetect2/train/preprocess.py
+++ b/src/batdetect2/train/preprocess.py
@@ -256,8 +256,17 @@ def preprocess_annotations(
     output_dir = Path(output_dir)
 
     if not output_dir.is_dir():
+        logger.info(
+            "Creating output directory: {output_dir}", output_dir=output_dir
+        )
         output_dir.mkdir(parents=True)
 
+    logger.info(
+        "Starting preprocessing of {num_annotations} annotations with {max_workers} workers.",
+        num_annotations=len(clip_annotations),
+        max_workers=max_workers or "all available",
+    )
+
     with Pool(max_workers) as pool:
         list(
             tqdm(
@@ -273,8 +282,10 @@ def preprocess_annotations(
                     clip_annotations,
                 ),
                 total=len(clip_annotations),
+                desc="Preprocessing annotations",
             )
         )
+    logger.info("Finished preprocessing.")
 
 
 def preprocess_single_annotation(
@@ -313,11 +324,15 @@ def preprocess_single_annotation(
     path = output_dir / filename
 
     if path.is_file() and not replace:
+        logger.debug("Skipping existing file: {path}", path=path)
         return
 
     if path.is_file() and replace:
+        logger.debug("Removing existing file: {path}", path=path)
         path.unlink()
 
+    logger.debug("Processing annotation {uuid}", uuid=clip_annotation.uuid)
+
     try:
         sample = generate_train_example(
             clip_annotation,
@@ -326,8 +341,9 @@ def preprocess_single_annotation(
         )
     except Exception as error:
         logger.error(
-            "Failed to process annotation: {uuid}. Error {error}",
+            "Failed to process annotation {uuid} to {path}. Error: {error}",
             uuid=clip_annotation.uuid,
+            path=path,
             error=error,
         )
         return