Capture One is a professional RAW file converter and image editing software specially designed for professional photographers, developed by Phase One from Denmark. It is mainly used for reading, organizing, editing, converting, printing and sharing RAW photos taken by digital cameras, and provides the best conversion quality and workflow to ease photographers' troubles bake at home. It is recognized as the standard among all RAW conversion software, and has been well received and trusted by users all over the world.

ACDSee (now called: ACDSee Photo Studio) was ever one of the long-standing (first released in 1994), most popular image browsing software that came with friendly UI, simple & humanized operation, high-quality and very fast image decoding method, comprehensive image formats support and powerful graphics file managing functions. All this won and accumulated the most users around the world for it (it basically was must-have especially for architecture and image processing related industries, including photography enthusiasts and professional graphic designers.

As for a good third-party image viewer to choose, before, I used to find XnView better than ACDSee, this is true, and i keep my point.But today i just found a better one than XnView - FastStone Image Viewer. If I could evaluate XnView with stars, I will give FastStone Image Viewer 4.5 or 5. Because it has a faster image reading speed than most of the image viewers (including XnView and ACDSee).