Hello Just been play with a feature I have not used before. First It would be clearer if on p20 of the thbook the paragraph under vthreshold If passages are _more_or_less_ vertical (inclination > vthreshold), even UD becomes perpendicular to the shot – otherwise passages would not look very good. The 'more or less' is very confusing It would read better if it read If passages are _about_ vertical (inclination > vthreshold), even UD becomes perpendicular to the shot – otherwise passages would not look very good. Also In some passages NSEW is not not always the best way to measure passages, rifts on the like. So for some I have dimensions measured as NW SE NE SW, possible allowing an ofset for vthreshold would be a way of solving this. eg vthreshold-offset 45 degree Just a thought for the future. thanks Andrew
I completely agree with you that NSEW is not not a good way to measure the shape of about-vertical passages. In fact I personally never measure dimensions in NSEW directions but in the direction of the shot (or of the preceeding shot if it is absolutely vertical), in the reverse direction, on its right and on its left. I use LRUD with Up meaning in the (horizontal direction of the shot and Down the opposite. As we have to give a bearing anyway for vertical shots, why not use it to orient the dimensions instead of a vthreshold-offset that should be changed for each new shot? Xavier Le 15/05/2012 11:04, Andrew Atkinson a écrit :
Hello
Just been play with a feature I have not used before.
First It would be clearer if on p20 of the thbook the paragraph under vthreshold
If passages are _more_or_less_ vertical (inclination > vthreshold), even UD becomes perpendicular to the shot – otherwise passages would not look very good.
The 'more or less' is very confusing
It would read better if it read
If passages are _about_ vertical (inclination > vthreshold), even UD becomes perpendicular to the shot – otherwise passages would not look very good.
Also
In some passages NSEW is not not always the best way to measure passages, rifts on the like. So for some I have dimensions measured as NW SE NE SW, possible allowing an ofset for vthreshold would be a way of solving this. eg
vthreshold-offset 45 degree
Just a thought for the future.
thanks
Andrew _______________________________________________ Therion mailing list Therion@speleo.sk http://mailman.speleo.sk/mailman/listinfo/therion
--
------------------------- Xavier Pennec Senior Research Scientist / Directeur de recherche Asclepios project-team, INRIA Sophia-Antipolis 2004 Route des Lucioles, BP93 F-06902 Sophia-Antipolis Cedex, France +33 4 92 38 76 64 +33 6 78 35 16 90 http://www-sop.inria.fr/asclepios/ -------------------------------
I also do as Xavier describes, and agree that compass bearing (even if clino is vertical) seems to be the logical way to orient LRUD. Bruce -----Original Message----- I completely agree with you that NSEW is not not a good way to measure the shape of about-vertical passages. In fact I personally never measure dimensions in NSEW directions but in the direction of the shot (or of the preceeding shot if it is absolutely vertical), in the reverse direction, on its right and on its left. I use LRUD with Up meaning in the (horizontal direction of the shot and Down the opposite. As we have to give a bearing anyway for vertical shots, why not use it to orient the dimensions instead of a vthreshold-offset that should be changed for each new shot? Xavier
On 15/05/12 21:37, Bruce wrote:
I also do as Xavier describes, and agree that compass bearing (even if clino is vertical) seems to be the logical way to orient LRUD. Bruce
Orientating to the passage has always been most logical to me, but I do see that the above is very valid. However what do you do on a true vertical, as it does not have a compass bearing?
-----Original Message----- I completely agree with you that NSEW is not not a good way to measure the shape of about-vertical passages. In fact I personally never measure dimensions in NSEW directions but in the direction of the shot (or of the preceeding shot if it is absolutely vertical), in the reverse direction, on its right and on its left. I use LRUD with Up meaning in the (horizontal direction of the shot and Down the opposite.
As we have to give a bearing anyway for vertical shots, why not use it to orient the dimensions instead of a vthreshold-offset that should be changed for each new shot?
Xavier
_______________________________________________ Therion mailing list Therion@speleo.sk http://mailman.speleo.sk/mailman/listinfo/therion
Orientating to the passage has always been most logical to me, but I do see that the above is very valid. However what do you do on a true vertical, as it does not have a compass bearing?
I just adopt a compass bearing to suit the general trend of the preceding passage or to suit the orientation of the passage shape for the basis of the LRUD. Regardless of the compass bearing, the survey leg will still be vertical. In truth it is academic for me now, as mostly I use a disto and pda, so no more LRUD. Still for all my old data... Bruce
Le 15/05/2012 23:54, Andrew Atkinson a écrit :
On 15/05/12 21:37, Bruce wrote:
I also do as Xavier describes, and agree that compass bearing (even if clino is vertical) seems to be the logical way to orient LRUD. Bruce
Orientating to the passage has always been most logical to me, but I do see that the above is very valid. However what do you do on a true vertical, as it does not have a compass bearing?
For a true vertical, you can provide the bearing of the UP width. Most often, if it is not measured, I take by continuity the bearing of the previous or the next shot (this provides a much better 3D model than NSEW). If you whant to use NSEW, you can put 0 (UP=N). Whatever bearing you provide in the measurements will not influence the shot itself anyway. Xavier
-----Original Message----- I completely agree with you that NSEW is not not a good way to measure the shape of about-vertical passages. In fact I personally never measure dimensions in NSEW directions but in the direction of the shot (or of the preceeding shot if it is absolutely vertical), in the reverse direction, on its right and on its left. I use LRUD with Up meaning in the (horizontal direction of the shot and Down the opposite.
As we have to give a bearing anyway for vertical shots, why not use it to orient the dimensions instead of a vthreshold-offset that should be changed for each new shot?
Xavier
_______________________________________________ Therion mailing list Therion@speleo.sk http://mailman.speleo.sk/mailman/listinfo/therion
_______________________________________________ Therion mailing list Therion@speleo.sk http://mailman.speleo.sk/mailman/listinfo/therion
--
------------------------- Xavier Pennec Senior Research Scientist / Directeur de recherche Asclepios project-team, INRIA Sophia-Antipolis 2004 Route des Lucioles, BP93 F-06902 Sophia-Antipolis Cedex, France +33 4 92 38 76 64 +33 6 78 35 16 90 http://www-sop.inria.fr/asclepios/ -------------------------------
15.05.2012 18:43, Xavier Pennec написал:
I completely agree with you that NSEW is not not a good way to measure the shape of about-vertical passages. In fact I personally never measure dimensions in NSEW directions but in the direction of the shot (or of the preceeding shot if it is absolutely vertical), in the reverse direction, on its right and on its left. I use LRUD with Up meaning in the (horizontal direction of the shot and Down the opposite. We a use "forward" and "backward" measurements in addition to LRUD. It is common practice for our surveyors.
-- WBR, Vasily
participants (4)
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Andrew Atkinson -
Bruce -
Vasily Vl. Suhachev -
Xavier Pennec