Last Friday I went on a cave survey with a group of cavers. We used a combination of the Suunto Tandem (compass/clino) and the DistoX2 to perform the measurements for the survey. All notes were hand drawn on paper with pencil. Actually had a pretty productive day. We were in some fairly challenging wet cave and managed to get 184 feet of survey before we had to turn back because someone was cold from laying in wet cave. We hadn't expected the water in the passage (it's usually dry). Otherwise we could've gotten a lot more passage. The cave was barely wet enough to get our clothes damp. We ended up getting some survey in a high maze passage, but by that point we were already running cold and getting out of the water didn't help enough.

The biggest challenge of the day was setting points for taking measurements. It is really hard to get a point that you can sit behind when looking at the last point AND when looking at the next point. Imagine we have points A, B, and C. Because we use backshots to verify our data, you have to be able to line up B to A for the backshot of the compass, and you have to be able to line up B to C for the next frontshot. Our goal is less than 2 degrees (1 degree preferred) of disagreement between the shots which means that these compasses have to be lined up very well. Looking through a Suunto is challenging enough, but when you are laying on damp rocks trying to find a position that lets you see from one target to the next....it adds a whole new dimension. The DistoX makes it a lot easier to measure, but we like to verify the shots with backshots from another instrument.