Correct geometry before judging the final framing
The menu-by-menu reference is Lens & Geometry: all six tools, including every crop/guide control.
Check the lens match, level the photograph and correct perspective when needed. Then choose a crop that keeps important content clear of any empty transformed corners. A lens profile depends on matching metadata and available calibration; it is not proof that every edge is corrected perfectly.
Use Auto level or perspective when the image has reliable lines, guided correction when you can identify them yourself and manual controls when the automatic estimate is unsuitable. Geometry and crop have separate resets. The full reference below explains their effects and RAW-only fringe correction.
Lens & composition
The Lens & Geometry section holds lens correction, transform, defringe, chromatic aberration and orientation. The Crop toolbar has Precise crop edges for numeric boundaries.
Lens profile
At the top: what the lens database matched for the camera body and the lens the file names, each marked when it is not in the database. Type part of the maker or lens name to filter the lenses listed for the body's mount, for example Canon 28. Typing only searches. Click a result to apply it, or press Enter to choose the first match. Clear the search or press Escape to cancel it. The arrow beside the heading goes back to the file's own lens.
Lens corrections
- Correction data: Camera data uses what the maker wrote into the file; Lens database uses the matched profile.
- Corrections: which of distortion, vignetting and chromatic aberration to apply.
- Scale: zooms in to hide the edges that distortion correction pulls into view.
Orientation
Set the whole picture's orientation. Each choice appears once: As shot, Unrotated, Rotate 90° left, Rotate 90° right, Rotate 180°, Flip horizontally, Flip vertically, and the two combined rotate-and-flip choices.
As shot follows the camera's orientation tag. Unrotated uses the file's original pixel order. The other choices also start from that original order; choosing a rotation again does not add another turn. The combined choices rotate 90° right, then flip in the displayed direction. For small angle corrections, use Crop & straighten.
Defringe
Removes purple and green fringing at high-contrast edges. Method, Radius and Threshold control how it finds the fringes.
The separate Chromatic aberration tool works on Bayer RAW sensor data only. It has no effect on X-Trans RAWs, linear DNGs or JPEG/PNG/TIFF images. For those images, use Lens corrections with a matching profile, or Defringe.
Transform
- Vertical perspective and Horizontal perspective: manual correction for converging lines, such as buildings photographed from below.
Crop & straighten opens the single set of rotation, automatic/guided correction and crop-edge controls. Straighten and Crop edges live there, rather than being repeated in Transform.
Crop
Left, Top, Right, Bottom as fractions of the frame. The crop tool (R) is the easier way: drag the handles or edges, pick a ratio, or straighten the photo. The Straighten slider covers −10° to 10° for small corrections. Hold Shift while dragging for finer control, or click the angle to type a value up to ±45°. Double-click the track to reset rotation. The composition grid offers thirds, golden, diagonals or none. Escape closes the tool.
With a ratio locked, dragging an edge keeps the crop centred on the other axis. A corner responds to horizontal and vertical movement, and the ratio stays locked at the photo boundaries. Each completed drag is one undo step; closing the tool during a drag cancels that unfinished movement. Original follows the photo's selected orientation. Choosing a ratio or swapping landscape and portrait fits the frame in one undoable step.
Automatic geometry and guides
Open Crop and straighten (R):
- Auto level finds clear horizontal and vertical edges and levels the photo. If it cannot find reliable lines, the photo stays unchanged and Draw level line switches on automatically.
- Draw level line: click the button, then drag along a horizon or an edge that should be horizontal or vertical. Release to straighten. Only one line is needed. Click the button again to cancel.
- Auto perspective offers Vertical, Horizontal and Full. Use Vertical for leaning buildings; Full needs clear lines in both directions.
- Draw perspective guides: click the button, then drag along two edges that should be vertical or two that should be horizontal. Draw four guides to correct both directions, then choose Apply guides. This mode also opens when Auto perspective cannot find a correction. Clear guides starts again; Cancel guides leaves the photo unchanged. Resizing the window preserves completed guides.
- Crop edges trims the empty corners produced by rotation and perspective. Largest keeps the largest usable area; Original keeps the original aspect ratio. Off shows the full transformed frame. The policy also follows manual rotation and perspective changes.
- Reset geometry resets rotation and perspective while preserving the crop frame and other adjustments. Reset crop frame restores the whole frame and Free aspect ratio while keeping geometry.
Corrections appear in the preview and each is one undoable history step. Automatic correction needs clear straight edges; portraits and organic scenes may need Draw level line or manual rotation instead.