The SK file format stores data in the SK format. Converting to NEF produces a image file that stores data in the NEF format. This renders each page as a raster image, making the content viewable without a document reader. Each page is rendered at the specified DPI and saved as a separate image; text in the output is no longer selectable. This makes NEF the practical choice when the destination system requires it or when the original format is not supported by the target application. 1converter runs this conversion on the server: your file is uploaded encrypted over HTTPS, converted using trusted open-source libraries, and the output is held for 24 hours before automatic deletion.