The Nik Collection of plugins for Adobe Photoshop and Lightroom and for Apple Aperture, bought by Google in late 2012, are now offered for free.
The plugins are the following ones:
- Analog Efex Pro: simulation of analog films.
- Color Efex Pro: various color filters.
- Silver Efex Pro: black and white treatments.
- Viveza: colors/contast enhancements.
- HDR Efex Pro: high dynamic range images treatments.
- Sharpener Pro: advanced sharpening.
- Dfine: noise reduction.
All plugins are highly configurable and support localized corrections via so called control points. One tutorial video on using control points is here:
The plugin package can be download at this link.