Need help configuring Linux motion

I need someone who is VERY familiar with the program called motion for Linux. It will be used with mjpg-streamer and the problem I am having is fine tuning it for my needs. I require that motion save just one image when there is movement. This means that it needs to save the very best that is as clear as possible. I cannot have many images being saved as this is using up the space. If you know motion VERY well, please contact me.