While many professionals use big and complex software to edit photos, you can do what you need with the small and cozy apps. There are a few simple and powerful programs for photo editing that you can use as you need.
GIMP. It is popular and often compared even to Photoshop. It contains many advanced options that help you to work with your photos as the specialist. It also has the interface similar to other popular image editors so it will be simple to understand it. GIMP doesn’t contain any ads or limitations for users.
Paint.NET. The version of the Paint editor designed for the .NET platform. It has much more features than the classic version had. It supports layers and filters, and also different plugins so can be used even for difficult image editing tasks. However, it has fewer features than GIMP.
Photo Pos Pro. It offers you the smart interface which would be convenient for most of the people who edit images. It also has several modes, beginner and advanced, so anyone can customize this program according to their skills. The file export is limited.
PhotoScape. Except for usual image editing features, it supports the raw file conversion. There is also the very useful selection of filters. However, this interface is not very usual to most of the modern customers.