diff --git a/Program.cs b/Program.cs
index 224d230..ada0c1b 100644
--- a/Program.cs
+++ b/Program.cs
@@ -38,15 +38,7 @@ public class FpsCounter {
 
 
 public class CameraInfo {
-  public readonly Vector2i Resolution;
-
-  private CameraInfo(Vector2i resolution) {
-    Resolution = resolution;
-  }
-
-  public static readonly CameraInfo NIKON_D7000 = new(new Vector2i(4928, 3264));
-  public static readonly CameraInfo CANON_EOS_R6M2 = new(new Vector2i(6000, 4000));
-  public static readonly CameraInfo IPHONE_12_MINI = new(new Vector2i(4032, 3024));
+  public static float AspectRatio = 6000f / 4000f;
 }
 
 
@@ -61,12 +53,12 @@ public class Transform {
   // FIXME: move scale and offset into Photo itself?
   float activeScale;
   Vector2i activeOffset;
-  Photo photo;
+  Vector2i photoSize;
 
-  public Transform(float scale, Vector2i offset, Photo photo) {
+  public Transform(float scale, Vector2i offset, Vector2i photoSize) {
     activeScale = scale;
     activeOffset = offset;
-    this.photo = photo;
+    this.photoSize = photoSize;
   }
 
   public Vector2i ScreenToImageDelta(int x, int y) {
@@ -76,8 +68,8 @@ public class Transform {
   public Vector2i ScreenToImage(int x, int y) {
     int rx = (int) ((x - activeOffset.X) / activeScale);
     int ry = (int) ((y - activeOffset.Y) / activeScale);
-    rx = Math.Clamp(rx, 0, photo.Size.X);
-    ry = Math.Clamp(ry, 0, photo.Size.Y);
+    rx = Math.Clamp(rx, 0, photoSize.X);
+    ry = Math.Clamp(ry, 0, photoSize.Y);
     return new(rx, ry);
   }
 
@@ -199,8 +191,8 @@ public class CropTool : ITool {
     Vector2i end = mouseDragEnd;
     // FIXME: choose the aspect ratio based on the original image aspect ratio.
     // FIXME: allow for unconstrained crop, 1:1, etc.
-    end.Y = Math.Min(end.Y, start.Y + (end.X - start.X) * 4 / 6);
-    end.X = start.X + (end.Y - start.Y) * 6 / 4;
+    end.Y = Math.Min(end.Y, (int) (start.Y + (end.X - start.X) / CameraInfo.AspectRatio));
+    end.X = (int) (start.X + (end.Y - start.Y) * CameraInfo.AspectRatio);
     int left = Math.Min(start.X, end.X);
     int right = Math.Max(start.X, end.X);
     int top = Math.Min(start.Y, end.Y);
@@ -270,7 +262,6 @@ public class Texture : IDisposable {
 
 public class UiGeometry {
   public static Vector2i MIN_WINDOW_SIZE = new(1024, 768);
-  private static CameraInfo activeCamera = CameraInfo.CANON_EOS_R6M2;
 
   public readonly Vector2i WindowSize;
   public readonly Box2i ThumbnailBox;
@@ -286,7 +277,7 @@ public class UiGeometry {
 
     int numThumbnails = Math.Max(WindowSize.Y / 100, 1);
     int thumbnailHeight = WindowSize.Y / numThumbnails;
-    int thumbnailWidth = (int) 1.0 * thumbnailHeight * activeCamera.Resolution.X / activeCamera.Resolution.Y;
+    int thumbnailWidth = (int) (1.0 * thumbnailHeight * CameraInfo.AspectRatio);
 
     Console.WriteLine($"thumbnail size: {thumbnailWidth} x {thumbnailHeight}");
     for (int i = 0; i < numThumbnails; i++) {
@@ -444,7 +435,7 @@ public class Game : GameWindow {
   Vector2i mousePosition;
   float activeScale = 1f;
   Vector2i activeOffset;
-  Transform transform = new(1f, Vector2i.Zero, null);
+  Transform transform = new(1f, Vector2i.Zero, Vector2i.Zero);
   Shader shader = new();
   Matrix4 projection;
   float zoomLevel = 0f;
@@ -816,7 +807,7 @@ public class Game : GameWindow {
     Vector2i center = (Vector2i) geometry.PhotoBox.Center;
     Box2i photoBox = Util.MakeBox(center.X - renderSize.X / 2, center.Y - renderSize.Y / 2, renderSize.X, renderSize.Y);
     activeOffset = new(photoBox.Min.X, photoBox.Min.Y);
-    transform = new Transform(activeScale, activeOffset, activePhoto);
+    transform = new Transform(activeScale, activeOffset, activePhoto.Size);
     DrawTexture(active, photoBox);
     for (int i = 0; i < 5; i++) {
       Texture star = (activePhoto.Rating > i) ? STAR_FILLED : STAR_EMPTY;