Yes And No
A picture on a Pentax K10D can be set to black and white. RAW photos cannot be set to black and white.
Filters
There are a number of filters that can be used on a Pentax K10D. They include color, sepia, soft, brightness, slim, and black and white.
Set Filters
The playback menu must be used to set a black and white filter. While in playback mode, the Fn button must be pressed.
Four-Way Controller
The four-way controller is also used in selecting the image filter.
Adjustments And Finish
The front and rear e-dial will be used to make any adjustments; press the "OK" button to save the picture using the four-way controller. Once saved the OK button must be saved again.