In response to Franks M27 (excellent may I say) here is a fantastic image by Richard Crisp using just Ha and OIII that clearly shows a jet eminating from the central star in the Dumbell. The jet in the forground is coming out of the page ending in a red flame like feature in front of and to the right of the main nebula while the flame at the end of the corresponding rearward shooting jet can be seen just above the outer edge of the main nebula at the 10 oclock position:
http://www.narrowbandimaging.com/ima...x30min_xga.jpg
A remarkable image!
Mike