Thanks Neville - I was using a Canon PowerShot S3is - the lens is not interchangeable. To be honest, you don't need anything fancy as you stand on the canal bank and the canal is only 100m wide. When I say the canalbank, I was about 2 feet away from the water - access is very easy and there is an excellent towpath - watch out for cyclists!
Hi Shipmate17, I drove down to a place called Klein Konigsforde and parked at the canal side (54 21 11.12N, 9 53 22.46E). I didn't know where to go, so I looked at the canal on Google Earth and found a couple of places that looked good access and easy walking alongside. It's a very good place as you can walk a good distance while waiting. Thoroughly recommend it, although the weather helped!