DXO Viewpoint in Use
Import a photograph by selecting either File > Open or drag drop an image onto the workspace. If using Photoshop, then images can be sent directly to Viewpoint via the Filter > DXO Labs option. Click on a Keystoning option, Vertical, Horizontal or Rectangle. Guide lines appear on the image, the line colour can be changed to contrast with the image that is being corrected. Drag an anchor point to the base position of an image, then position the top anchor to the top position, make sure that the line follows an upright line in the photo. Repeat the process on the other line, making sure that the line follows an upright. Use the Visualization Loupe to accurately place the anchor points.
Once positioned click on the small Refresh Display icon, this can be found near the last anchor point used. The image is corrected instantly with a greyed out crop area, from here you can make any adjustments by either re positioning the anchor points or by using the Keystoning Advanced options.
Use the Grid display to make sure the uprights are totally upright. The overlay grid can be re-sized from 5 to 200 pixels, 100 is the default, unfortunately the grid colour is always white. Once you are satisfied with the result click on the Apply button. Use the Before and After views to check the image or press Ctrl+D to switch between the original and corrected versions. To make any further adjustments just select the Keystoning option again and the screen returns to the state before clicking on the Apply button.
When done save the image as either a JPEG or TIFF file, if you are using Viewpoint as a Photoshop or Lightroom plug-in then click on the Save button to return the image back to the host application. The Keystoning Rectangle is used to correct photos which need to be squared up, this option allows you to perform both vertical and horizontal corrections at the same time.