The pilot was participating in a "ridge soaring camp". After becoming airborne the glider was flown at low level in a south-westerly direction along the ridge line, about 200 feet above the ridge. The pilot then turned the aircraft left towards the ridge in an attempt to gain lift. No lift was gained and the aircraft descended. The pilot then raised the nose of the aircraft to clear the ridge but the right wing struck a tree. The aircraft slewed to the right and descended down the ridge line before impacting the ground. The pilot had intended to turn back towards the ridge but delayed this turn to allow her passenger to take a photograph. The resultant flight path took the aircraft into an area of sink on the leeward side of the ridge. The pilot usually flew the glider from the front cockpit but due to centre of gravity considerations she had to use the rear cockpit which somewhat restricted her forward vision. The volume of the variometer, which was fitted in the front cockpit, was turned down so as not to disturb the passenger, however this action also deprived the pilot of immediate indication of changes in lift. This accident was not the subject of an on-site investigation.