Crop & Transform a Photo

Directly out of a camera, your digital photos will likely not be sized to the exact dimensions you need.  Between different shaped screens, web pages, social networks, and prints, it’s common to change the shape and size of an image. Inside of Aurora HDR 2019 you have options such as cropping which changes the shape of a photo, and transforming which scales the image inside the canvas. You can use these choices individually or in combination to achieve the desired results. Additionally, a photo can be transformed to counteract lens issues.

Cropping a Photo

With the Crop tool you can change a viewer’s perception of an image. You can choose to tighten the area of interest, which allows you to de-emphasize (or even eliminate) parts of a photo and improve the image by better framing the subject. An additional benefit is that the Crop tool can also be used to align (straighten) the horizon in an image.

1. Open an image that needs cropping or straightening.
2. Switch to Crop tool by click the Scissors button in the top toolbar or press the C key. 
After pressing this button, the application enters Crop Tool Mode.
   
   
3. Examine the top Info Bar which displays all functions for cropping an image.
4. Choose a ratio from the Aspect drop-down menu.
• Free – Create a custom shape by dragging to taste.
• Original – Preserves the original shape of the photo but allows you to crop more tightly to remove details from the edges
• Transposed – The original dimensions are reversed for the crop.
• 16:10 – A ratio that matches many computer displays
• 16:9 – A ratio used by televisions, many electronic devices and presentations
• 11:8.5 – A common size for documents.
• 7:5 — A rectangular image that’s common for many photo sizes
• 5:4 – A nearly square image that’s common for many photo sizes
• 4:3 – A rectangular image that’s common for many photo sizes
• 3:2 – A rectangular image that’s common for many photo sizes
• 1:1 – A square shaped image
• 2:3, 3:4, 4:4 5:7, 8.5:11, 9X16, and 10:16 – Presets that match the standard print and screen ratios, but with their values transposed
• Facebook Cover – A useful size for a page banner on Facebook™️
• Facebook Feed – A common size for an image post to Facebook
• Enter Custom… – Offers the ability to choose a specific aspect ratio
5. Choose a ratio overlay to help with cropping.
• Rule of Thirds – This is an over-used standard for cropping. The four intersecting points are considered  the best place to put a subject.  Many feel that following these guides makes an image appear better.
• Phi Grid — The phi grid is similar to the rule-of-thirds grid. The differences are that the parallel lines are closer to each other and to the center of the frame, and the nine boxes are not all the same size. This grid can better accommodate the Golden Ratio.  Many landscape photographers feel that this is a better guide for composition than the rule of thirds.
  
  
  The Rule of Thirds overlay on the left is the default overlay when cropping. The Phi Grid on the right is an alternative overlay to help when cropping.
  
6. Drag any of the corners or resize handles to modify the cropping rectangle.
   
7. To Move the image inside the crop, just click inside the image crop area and drag to reposition the image “behind” the cropping rectangle.
8. To Rotate an image, you can click on the Angle readout to reveal a drop-down slider for adjusting the angle of the image up to 45 degrees in either direction. You can also click and drag just outside a corner to rotate.  A grid overlay appears to help you with accurate cropping.
9. When happy with the cropping, click the Done button. To cancel this action click Cancel. 
If you do not like the result, you can easily undo the cropping by clicking the Undo button. Hence cropping is a safe operation that can be easily undone.
   
   

Additional Options When Cropping

Inside the Crop tool, you’ll find a few other useful commands.

• Click the Flip button to reverse the left and right sides of the image.
• Click the Flop button to reverses the top and bottom parts of an image.
• Click the Rotate button to turn the canvas in 90˚ increments.
  

Transforming a Layer

Once you’ve merged brackets, opened a photo, or added a new layer to a document, it’s easy to transform it.  With the Transform tool there are many options available for changing the position, rotation, and scale of a layer.

1. Open a photo or merge a series of brackets to create a new image.
2. While on the base or initial layer, click the Transform button near the top of the Filters controls.
The image can now be transformed.
3. Adjust any of the following properties as needed to transform the image:
• Vertical – This tilts the image by rotating it on the X-axis.  This tilts the image forwards or backwards and can help compensate for an image with any keystoning problems.  This type of problem causes vertical lines to appear skewed and is often caused by the camera shooting from an angle by rotating on the Y-axis.  This angles the image from side to side and solves the problems caused by shooting at an angle above or below in relation to the subject.
• Horizontal – This adjustment tilts the image on the Y-axis.  It can help compensate for perspective issues caused by shooting off-angle from your subject.
• Rotate – Rotates the entire canvas on the Z-axis and can be useful for straightening a crooked photo.
• Aspect – This command changes the aspect ratio of a photo. Dragging the slider will expand the height or the width while contracting the opposite direction for the second value.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
• Scale – Use the Scale command to effectively crop the transformed photo.  This is a useful way to hide gaps after transforming a photo.
  
  
• X Offset This shifts the transformed image left or right.
  
• Y Offset This shifts the transformed image up or down.
4. When finished, click the Done button to use the Transform settings.
   
   

Applying Lens Correction to a Layer

The new Lens Correction command easily fixes all kinds of lens distortion, from barrel and pincushion to chromatic aberration and vignetting.  This is a useful way to compensate for flaws caused by the lens.

1. Open a photo or merge a series of brackets to create a new image.
2. Click the Lens Correction button near the top of the Filters controls.
The image can now be corrected.  Any filters applied will be temporarily disabled while in Transform mode.
   
   
3. Adjust any of the following properties as needed to transform the image:
• Distortion – Drag to the left to increase the barrel shape of the lens.  Drag to the left to pinch and compensate for wider angle lenses. You may need to crop the layer or use the Scale command in the Transform controls to compensate for gaps at the edges.
  
  The image on the left shows distortion from a wide-angle lens.  On the right, some of the unwanted curvature has been corrected.
• Defringe – This option is useful to remove fringe colors along edges.  This can occur along detailed edges in a subject, especially where there’s a sharp change in color values.
• Remove CA (Chromatic Aberration) – Chromatic aberration is another type of color fringing.  It often happens on telephoto lenses and in areas of high contrast.  It tends to show up as magenta or green edges.
• Devignette – Removes any darkening at the edges of an image caused by the lens itself.   This is a corrective command, not a stylizing command.  If you want an artistic vignette, use the Vignette filter.
  
  

The image on the left shows darkening along the outer edges caused by the lens.  The image on the right has had its edges lightened with the Devignette command.  If you want a stylistic vignette, use the Vignette filter.