diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0c0dcf8..6168f16 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Automatic HEIC/MPO to JPEG conversion (browsers cannot display these formats)
 - Graceful error handling if pillow-heif library not installed
 
+### Changed
+
+- Increased maximum input image dimensions from 4096x4096 to 12000x12000 to support modern phone cameras (48MP+); images are still optimized to smaller sizes for web delivery
+
 ### Dependencies
 
 - Added `pillow-heif` for HEIC image processing
diff --git a/starpunk/media.py b/starpunk/media.py
index af981b6..dd5db7b 100644
--- a/starpunk/media.py
+++ b/starpunk/media.py
@@ -38,7 +38,7 @@ ALLOWED_MIME_TYPES = {
 # Limits per Q&A and ADR-058 (updated in v1.4.0)
 MAX_FILE_SIZE = 50 * 1024 * 1024  # 50MB (v1.4.0)
 MAX_OUTPUT_SIZE = 10 * 1024 * 1024  # 10MB target after optimization (v1.4.0)
-MAX_DIMENSION = 4096              # 4096x4096 max
+MAX_DIMENSION = 12000             # 12000x12000 max input (v1.4.2 - supports modern phone cameras)
 RESIZE_DIMENSION = 2048           # Auto-resize to 2048px (default)
 MIN_QUALITY = 70                  # Minimum JPEG quality before rejection (v1.4.0)
 MIN_DIMENSION = 640               # Minimum dimension before rejection (v1.4.0)
@@ -194,7 +194,8 @@ def validate_image(file_data: bytes, filename: str) -> Tuple[bytes, str, int, in
     else:
         raise ValueError("Could not determine image format")
 
-    # Check dimensions
+    # Check dimensions (v1.4.2: increased to 12000px to support modern phone cameras)
+    # Images will be resized by optimize_image() anyway
     width, height = img.size
     if max(width, height) > MAX_DIMENSION:
         raise ValueError(f"Image dimensions too large. Maximum is {MAX_DIMENSION}x{MAX_DIMENSION} pixels")
diff --git a/tests/test_media_upload.py b/tests/test_media_upload.py
index 6ac67b2..280f142 100644
--- a/tests/test_media_upload.py
+++ b/tests/test_media_upload.py
@@ -127,8 +127,8 @@ class TestImageValidation:
         assert "File too large" in str(exc_info.value)
 
     def test_dimensions_too_large(self):
-        """Test rejection of >4096px image (per ADR-058)"""
-        large_image = create_test_image(5000, 5000, 'PNG')
+        """Test rejection of >12000px image (v1.4.2: increased from 4096)"""
+        large_image = create_test_image(13000, 13000, 'PNG')
 
         with pytest.raises(ValueError) as exc_info:
             validate_image(large_image, 'huge.png')