Pipeline Canyon is a very good canyon just off the Pipeline Track between Newnes and Glen Davis. It features two sections of canyon, though most parties miss out on the upper constriction and only visit the lower constriction.
See here for information on how to get to Newnes.
From the main (Little Capertee) campground at Newnes, follow the track along the left bank of the river for 2km to the bottom of the Pipeline Track to Glen Davis (signposted). There are some tracks leading to the left, away from the river, and these should be ignored. Crossing Petries Gully may involve wet feet. The bottom of the Pipeline Track is reached just after the Petries Gully crossing. Climb up to the top of the hill on the track. A side track leads to a good lookout about 100m walk to the SSE.
Returning to the main track, continue along to the watershed, where there is a National Parks sign about Starlight Canyon.
There are a couple of entry points you can use.
Follow the Starlight Canyon track off to the right, up and around the small hill to the east. Cross the next two saddles, and drop down from the slopes of the hill aiming for the bend in the creek around MGA452278 (AMG451276, Mount Morgan). There is a bit of a scramble to get down the bottom of the hill. Some parties may end up needing to abseil. Walk down the creek to the first canyon section.
A shorter route in (distance-wise) drops into the tributary to the right of the Pipeline Track, about 200m before you reach the watershed. There is a well-worn footpad leaving the Pipeline Track here. There are four abseils up to 10m before you reach the main creek, although a couple may be bypassed by careful scrambling. Note that this way in misses the first canyon section, and joins the main creek just after the second canyon section starts.
The first section of the canyon is not far. This has a number of easy climb downs, but no abseils, and is dry. There is an impressive narrow section with massive coachwoods stretching all the way to the top of the slot. The creek then opens up for a while before the next canyon section.
The second section starts with a short climb down, and some bridging to avoid pools, otherwise a short swim. The tributary mentioned above enters almost straight away. Not far on there is a 10m abseil into a pool, and then a 6m abseil down a log. A long flat section of canyon follows, with a few wades, and just as the canyon starts to open out a bit, there is another abseil.
This is about 15m, followed by a very awkward 4m drop. These can be combined, and made easier, with a 50m rope. However a recent tree fall will probably make combining the drops impossible for some time. There is a short swim, or traverse around the side of the pool. Then there is a short drop, with a tricky overhung start, though it is about 10m all up as the anchor is some distance back. The final abseil also has a slightly tricky start. This is about 15m (12m drop, plus a few metres to the anchor) down to the end of the canyon.
Head right under the cliffs on a somewhat exposed track, until you hit the Pipeline Track, which you can follow back to camp. Keep close to the cliffs to avoid a lower track on hairier ledges.