Paint.NET is free image editing and photo manipulation software designed to be used on computers that run Windows. It supports layers, unlimited undo, special effects, and a wide variety of useful and powerful tools. It started development as an undergraduate college senior design project mentored by Microsoft, and is currently being maintained by some of the alumni that originally worked on it. Originally intended as a free replacement for the MS Paint software that comes with Windows, it has grown into a powerful yet simple tool for photo and image editing.
The programming language used to create Paint.NET is C#, with a small amount of C++ for installation and shell-integration related functionality. Paint.NET can be used to enhance and clean up your photographs. Using the Clone Stamp tool, the power lines that criss-crossed in front of the Space Needle were carefully removed.
Other operations were performed that had the effect of smoothing out the image without blurring it, adding some "bloom" (glow), and increasing the contrast.
FEATURES:
Simple, intuitive user interface
Every feature and user interface element was designed to be immediately intuitive and quickly learnable without assistance. It is also designed to be immediately familiar to users of the original MS Paint software that comes with Windows.
Layers
Usually only found on expensive or complicated professional software, layers form the basis for a rich image composition experience. You may think of them as a stack of transparency slides that, when viewed together at the same time, form one image.
Powerful Tools
Paint.NET includes simple tools for drawing shapes, including an easy-to-use curve tool for drawing splines or Bezier curves. The Gradient tool, new for 3.0, has been cited as a huge improvement over similar tools provided by other software. The facilities for creating and working with selections is powerful, yet still simple enough to be picked up quickly. Other powerful tools include the Magic Wand for selecting regions of similar color, and the Clone Stamp for copying or erasing portions of an image. There is also a simple text editor, a tool for zooming, and a Recolor tool.
Unlimited History
Everybody makes mistakes, and everybody changes their mind. To accommodate this, every action you perform on an image is recorded in the History window and may be undone. Once you've undone an action, you can also redo it. The length of the history is only limited by available disk space.
Special Effects
Many special effects are included for perfecting your images. Everything from blurring, sharpening, red-eye removal, distortion, noise, and embossing are included. Also included is our unique 3D Rotate/Zoom effect that makes it very easy to add perspective and tilting.
Adjustments are also included which help you tweak an image's brightness, contrast, hue, saturation, curves, and levels. You can also convert an image to black and white, or sepia-toned.
Open Source and Free
Paint.NET is provided free-of-charge, and the source code (all 133,000 lines of it) is also available for free under generous licensing terms. The bulk of Paint.NET is written in C#, with only a small amount of code related to setup and shell-integration written in C++.
Changes in Paint.NET v3.5.1, released on November 19th, 2009:
This update adds a new feature for Windows 7 users, and fixes many small issues that have been found since 3.5's release.
* New: For Windows 7, added taskbar progress reporting for long running operations (effects, adjustments, Image->Resize, save, install)
* Made some corrections to the French translation
* Running setup with /auto will no longer launch Paint.NET when it's done
* Fixed an issue where Paste into New Image would refuse an image on the clipboard, even if regular Paste would take it
* Fixed a race condition with Edit->Paste and Image->Resize whereby it would take up 100% CPU and take between 1 minute to 1 hour to finish
* Fixed an issues with Copy/Paste where it would leave an extra line of transparent pixels on the left, top, right, and/or bottom edges
* Fixed lag with the paintbrush tool that was being seen on some systems
* Fixed some issues with the paintbrush and eraser tool being misaligned when zoomed in
* Fixed a crash that would happen at (seemingly) random times, such as after drawing with the paintbrush tool, on some systems
* Fixed a minor and obscure rendering glitch with the Move Selected Pixels tool
* Fixed an issue with glass over Remote Desktop or Windows 7 Virtual PC
* Fixed a minor glitch whereby the "Unsaved Changes" confirmation dialog could never finish rendering the image thumbnail if one of the Move tools was active
Homepage - http://www.getpaint.net
Size: 4.78 MB
Download Paint.NET 3.5.1 Final
Download Plugins
Download Microsoft .NET Framework 3.5 Service Pack 1 (Full Package)
Paint.NET is free image editing and photo manipulation software designed to be used on computers that run Windows. It supports layers, unlimited undo, special effects, and a wide variety of useful and powerful tools. It started development as an undergraduate college senior design project mentored by Microsoft, and is currently being maintained by some of the alumni that originally worked on it. Originally intended as a free replacement for the MS Paint software that comes with Windows, it has grown into a powerful yet simple tool for photo and image editing. 
