diff --git a/.github/workflows/check.yml b/.github/workflows/check.yml
index 782bb5e..0cb14a8 100644
--- a/.github/workflows/check.yml
+++ b/.github/workflows/check.yml
@@ -1,6 +1,8 @@
 name: Lint & build
 
-on: [push]
+on:
+  push:
+  workflow_dispatch:
 
 jobs:
   build:
@@ -15,7 +17,7 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         python -m pip install .[dev,cli]
-        python -m pip install opencv-python-headless>=4.8
+        python -m pip install 'opencv-python-headless>=4.8,<4.9'
     - name: Lint
       run: |
         make lint
diff --git a/april_vision/cli/marker_generator/marker_modes/mode_cal.py b/april_vision/cli/marker_generator/marker_modes/mode_cal.py
index 35c14dd..7bfa523 100644
--- a/april_vision/cli/marker_generator/marker_modes/mode_cal.py
+++ b/april_vision/cli/marker_generator/marker_modes/mode_cal.py
@@ -111,7 +111,7 @@ def main(args: argparse.Namespace) -> None:
 
 def create_subparser(subparsers: argparse._SubParsersAction) -> None:
     """Marker_generator subparser CAL_BOARD used to generate a calibration board."""
-    parser = subparsers.add_parser("CAL_BOARD")
+    parser = subparsers.add_parser("CAL_BOARD", help="Generate a calibration board")
 
     parser.add_argument(
         "--page_size",
diff --git a/april_vision/cli/marker_generator/marker_modes/mode_image.py b/april_vision/cli/marker_generator/marker_modes/mode_image.py
index 27cc48e..93fd72f 100644
--- a/april_vision/cli/marker_generator/marker_modes/mode_image.py
+++ b/april_vision/cli/marker_generator/marker_modes/mode_image.py
@@ -44,7 +44,7 @@ def main(args: argparse.Namespace) -> None:
 
 def create_subparser(subparsers: argparse._SubParsersAction) -> None:
     """Marker_generator subparser IMAGE used to generate an image of a marker."""
-    parser = subparsers.add_parser("IMAGE")
+    parser = subparsers.add_parser("IMAGE", help="Generate a bare marker as an image")
 
     parser.add_argument(
         "--marker_family", default=MarkerType.APRILTAG_36H11.value,
diff --git a/april_vision/cli/marker_generator/marker_modes/mode_single.py b/april_vision/cli/marker_generator/marker_modes/mode_single.py
index 3cdac2e..2b43042 100644
--- a/april_vision/cli/marker_generator/marker_modes/mode_single.py
+++ b/april_vision/cli/marker_generator/marker_modes/mode_single.py
@@ -1,5 +1,6 @@
 import argparse
 import logging
+from typing import Union
 
 from PIL import Image
 
@@ -8,7 +9,8 @@
 
 from ..marker_tile import MarkerTile
 from ..utils import (DEFAULT_COLOUR, DEFAULT_FONT, DEFAULT_FONT_SIZE, DPI,
-                     PageSize, mm_to_pixels, parse_marker_ranges)
+                     CustomPageSize, PageSize, mm_to_pixels,
+                     parse_marker_ranges)
 
 LOGGER = logging.getLogger(__name__)
 
@@ -20,7 +22,15 @@ def main(args: argparse.Namespace) -> None:
 
     marker_ids = parse_marker_ranges(tag_data, args.range)
 
-    page_size = PageSize[args.page_size]
+    page_size: Union[PageSize, CustomPageSize]
+    if args.page_size == 'CROPPED':
+        # Allow for an additional marker pixel border
+        required_width = args.marker_size * (
+            (tag_data.total_width + 2) / tag_data.width_at_border
+        )
+        page_size = CustomPageSize(required_width, required_width)
+    else:
+        page_size = PageSize[args.page_size]
 
     marker_pages = []
 
@@ -142,7 +152,7 @@ def main(args: argparse.Namespace) -> None:
 
 def create_subparser(subparsers: argparse._SubParsersAction) -> None:
     """Marker_generator subparser SINGLE used to generate a PDF of a marker."""
-    parser = subparsers.add_parser("SINGLE")
+    parser = subparsers.add_parser("SINGLE", help="Generate a single marker per page")
 
     parser.add_argument(
         "--all_filename",
@@ -166,7 +176,7 @@ def create_subparser(subparsers: argparse._SubParsersAction) -> None:
         "--page_size",
         type=str,
         help="Page size of output files (default: %(default)s)",
-        choices=sorted([size.name for size in PageSize]),
+        choices=sorted([size.name for size in PageSize] + ["CROPPED"]),
         default="A4",
     )
     parser.add_argument(
@@ -229,7 +239,7 @@ def create_subparser(subparsers: argparse._SubParsersAction) -> None:
     parser.add_argument(
         "--border_width",
         help="Size of the border in pixels (default: %(default)s)",
-        default=1,
+        default=4,
         type=int,
     )
     parser.add_argument(
@@ -241,7 +251,7 @@ def create_subparser(subparsers: argparse._SubParsersAction) -> None:
     parser.add_argument(
         "--tick_length",
         help="Length of center tick lines in pixels (default: %(default)s)",
-        default=10,
+        default=40,
         type=int,
     )
 
diff --git a/april_vision/cli/marker_generator/marker_modes/mode_tile.py b/april_vision/cli/marker_generator/marker_modes/mode_tile.py
index 1c8b6d6..1c2b7dd 100644
--- a/april_vision/cli/marker_generator/marker_modes/mode_tile.py
+++ b/april_vision/cli/marker_generator/marker_modes/mode_tile.py
@@ -149,7 +149,7 @@ def create_subparser(subparsers: argparse._SubParsersAction) -> None:
     Marker_generator subparser TILE.
     Used to generate a PDF with multiple markers per page.
     """
-    parser = subparsers.add_parser("TILE")
+    parser = subparsers.add_parser("TILE", help="Generate multiple markers per page")
 
     parser.add_argument(
         "--all_filename",
@@ -230,7 +230,7 @@ def create_subparser(subparsers: argparse._SubParsersAction) -> None:
     parser.add_argument(
         "--border_width",
         help="Size of the border in pixels (default: %(default)s)",
-        default=1,
+        default=4,
         type=int,
     )
     parser.add_argument(
@@ -242,7 +242,7 @@ def create_subparser(subparsers: argparse._SubParsersAction) -> None:
     parser.add_argument(
         "--tick_length",
         help="Length of center tick lines in pixels (default: %(default)s)",
-        default=10,
+        default=40,
         type=int,
     )
 
diff --git a/april_vision/cli/marker_generator/utils.py b/april_vision/cli/marker_generator/utils.py
index 5e0073c..0eef21f 100644
--- a/april_vision/cli/marker_generator/utils.py
+++ b/april_vision/cli/marker_generator/utils.py
@@ -2,7 +2,7 @@
 from enum import Enum
 from typing import List, Tuple
 
-from font_roboto import Roboto  # type: ignore[import]
+from font_roboto import Roboto  # type: ignore[import,unused-ignore]
 
 from april_vision.cli.utils import ApriltagFamily, parse_ranges
 
@@ -59,3 +59,19 @@ def pixels(self) -> Tuple[int, int]:
             mm_to_pixels(self.value[0]),
             mm_to_pixels(self.value[1]),
         )
+
+
+class CustomPageSize:
+    """
+    Class to define a custom page size
+    """
+    def __init__(self, width: int, height: int) -> None:
+        self.width = width
+        self.height = height
+
+    @property
+    def pixels(self) -> Tuple[int, int]:
+        return (
+            mm_to_pixels(self.width),
+            mm_to_pixels(self.height),
+        )