I'm using Adobe Photoshop Lightroom which did pretty much the entire conversion for me. The really cool thing about Lightroom after simply clicking on "grayscale" is to go into the saturation section and click onto a button where you can take an arrow over a specific part of an image, click with the mouse and it will automatically increase or decrease saturation within that specific tone.
Handy for colour images but also extremely handy for black and white as it brings in the perfect mix of colour for whatever tone you select. Really takes the guesswork out of tonal enhancements in black and white.
Moraine Lake Oregon (26)