The Overlay tool is an advanced composition aid and is commonly used when shooting tethered. This function is often used to capture an image that will match a specific layout. For example, an image could be made for a magazine cover specifically to take into account the space required for a nameplate or masthead and cover lines. The tool is located by default in the Capture tool tab and it is also available to use in the Live View tool tab when working with Live View.
While you can load a JPEG file as an overlay, it makes the most sense to use a file format with a transparent background layer in order to be able to see the captured images beneath. Capture One’s Overlay tool is compatible with the majority of popular file formats that support transparency, such as TIFF, PNG, and GIF. In addition, Mac users can also use PSD and PDF files, while Windows users can use BMP files. Transparency support will ensure that the overlay can be displayed clearly over the image in the Viewer.