Cave-Surveying Digest, Vol 12, Issue 1

[Pat Kambesis]

I think the reasoning behind going for longer shots instead of shorter ones is that with fewer survey stations, it is statistically possible to make fewer errors.  However the longer the shot, the more difficult it is to site accurately.  Digital instruments can greatly minimize user error since the reader doesn't have to assume contorted positions to read the shot and  are a lot easier to learn to use accurately than suuntos.

Regardless of which types of instruments are used (digital vs analog), the biggest limitation on the survey  is the speed (or rather efficiency) of the sketcher.  Even if one could shoot accurate 100 meter long legs, the sketcher still needs time to accurately record data and make the sketches (sketching to scale in plan, profile, cross sections).  "Eyeballing" a very long shot in terms of making the sketch i.e. no distance reference, is very difficult with shots that are much longer than 30 meters - one can't "eye" estimate where to place passage/wall details with much accuracy with distances greater than 15 meters (my personal experience).

pk







____________________________________________________________
Click for information on obtaining a VA loan.
http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m3mWXpUKp8wX7iZfRap5QNWR2WPMEhjIknfAftlR8ZXbtEz/