On 25/01/11 19:21, Bruce wrote: > Firstly Iâd like to thank Beat for; > > -developing the DistoX and for the regular improvements to PocketTopo, > > -repairing our DistoX when it was faulty after our initial assembly, and > > -âwalkingâ me through and troubleshooting on numerous times Iâve been > confused or one of the devices was not working.
I will second that, its adaptability keeps amazing me, just done a survey in a cave with too much metal to use a compass, therefore had to use a total station, it does not do negative inclination but give out 350 for -10. Pocket Topo took it in its stride. (therion gives an error, which I will mail about shortly) > > We just found 2.5km of 10-30m diameter passage, and would not have been > able to face surveying with a tape measure and paper (too slow and > inaccurate). Itâs big muddy light absorbing passage. Having launched > into the project I have a suggestion for PocketTopo development, (and > distoX observations) that the forum might like to comment on. Well done, sounds like fun, do we get to see a survey soon? > > *PocketTopo v1.35* Must upgrade to this! > <snip> > shots and â.â shots). > > *Disto Distance* > > Our distoX occasionally gives one off spurious distance (and rarely > compass) readings. On our most recent trip it went one step further â a > ~15m survey leg gave â3 in a rowâ readings of 0.21m and some time later > (after many readings that looked OK) on a similar ~15m survey leg it > gave â8 in a rowâ 52.0m readings with the odd 48m and 82m reading thrown > in for good measure. We chose another station and the anomaly > disappeared. We are quite sure that for the majority of these bogus > readings the laser was squarely on the target. This survey (but not > these legs) included a 100m loop, which closed at 1.25%. This is among > the worst weâve had with the distoX, but it does not suggest any gross > distance errors occurred within the loop. > > Some 100 distance readings later the lithium AAA batteries died. (The > indicator suggested the batteries were full at the start, and the survey > included probably 300 shots). > > Has any one else noticed similar issues? > > Are the spurious readings likely to be battery level related? Or do they > suggest something more sinister? In reverse order, for lithium batteries when they die they die quickly, all bars showing to dead in less than 10 shots. I have no idea how many reading the distoX takes on one set, but it must be thousands, I am on my second set, and covered many km's of passage, with splays, it must be about 1 leg per metre. As for the spuriuos distance reading, yes occasionally, but never 3 of similar length together, it usually occurs in damp or drippy areas, we have also managed to reflect it off a wet surface of a wall or a pond, and get a more consistent error, but not enough to form a leg in PocketTopo. I have seen silly short measurements, again in damp conditions, usually with steaming or muddy front, not necessarily on the lens, can be on the rubber bit round the edge. I have not been able to reproduce it back at home, when I try to it just works or does not work. Also on 2 occasions the clino has 'frozen' repeatedly given the same measurement, while the distance and the bearing seemed fine. both times I have had to calibrate the DistoX to fix the problem From my experience 1.25% seems a little high for a loop closure using a DistoX. Since using DistoX anything above 0.5 is suspicious, I regularly get 0.0 (the output is only 1 dp) > > *Disto Display* > > A new distoX, recently acquired and upgraded by a colleague has > developed some permanently âlitâ pixels (about 20 of them) in the middle > of where the inclination is displayed â even when the device is powered off. > > He is a âdistoX & paperâ surveyor (and like me has aging eyes) so the > difficulty in reading the display is particularly frustrating. > > Is there a solution to this? > > -New display from Leica? > > -New circuit board from Leica? I have some weird lines on one of mine, so might need a solution to this soon as well, let's face it they were not built for caving Andrew
