Ed W
Member
Darkplaces,
Don't get put off by people making this out to be more complicated than it needs to be. It is very easy to get overly anal about surveying, the techniques you use must be balanced against what you wish to achieve with the survey and the time you have available to carry it out (rarely important in the UK but vital on expeditions where time inthe field is limited and some sort of survey is better than none). You don't even have to correct for magnetic/grid north if you don't want to, simply draw the survey to magnetic north and state that you have done this and the date that the readings were taken. This will then allow someone in later years to make the correction themselves if they want/need to.
If all you want to do is to be able to illustrate a new section of passage, then your silva compass and no clino in this case will be fine. Once drawn up, whether using a computer or hand drawn, it will allow people to see what is there. In this case it will not matter too much if the whole thing is swivelled by a degree or two. This should even be OK over multiple trips as long as the same instruments are used, and the same person takes the readings. However it is worth stating what techniques and equipment was used so that future users of the survey know its limitations (this should be done for any survey).
However, if you wish to use the survey for anything more ambitious, such as seeing if what you have found may link to something else for instance, then you really do need to start employing techniques such as compass callibration and just as importantly know where the entrances are in relation to each other. However this takes extra time and effort. Equally the point about adding extra information is quite correct. However if you listen to everyone's idea of what is vital information to take you will spend forever looking for it and writing it down. My suggestion is to note what you think is relevant, as you gain more experience you will note more.
In short go for it. Do your surveying how you want to do it (taking as much advice as you want), but someone willalways complain about what you haven't done! However, surveying is a much misunderstood activity. The perception of boring/cold trips is totally wrong. There are few ways of fully understanding or appreciating a cave/mine than by surveying it and the satisfaction of producing the final map is fantastic. You will learn far more by actually going out and trying things out and making mistakes than by absorbing any amount of reflected wisdom (as useful as that may be).
As to the computer versus hand drafting? I use a computer programme (already mentioned on here so I will not repeat) to generate centreline information, and then hand draft, scan and add text. I know Ouan's work very well (I helped him with some of it) and he uses a fully computer generated method. In Ouan's case the program allows him to add passage detail, and then distirt it with changes to the centreline detail as he is working in long complex systems in asia where trips are made over many years. Oviously if you used my method to do this you would have to redraw the detail after every trip. However most of my work is in short isolated caves, so it is rare that we have to do any redrafting. I would also challenge anyone to suggest that Ouan's presentation is inferior in any way to that produced by hand drafting.
Don't get put off by people making this out to be more complicated than it needs to be. It is very easy to get overly anal about surveying, the techniques you use must be balanced against what you wish to achieve with the survey and the time you have available to carry it out (rarely important in the UK but vital on expeditions where time inthe field is limited and some sort of survey is better than none). You don't even have to correct for magnetic/grid north if you don't want to, simply draw the survey to magnetic north and state that you have done this and the date that the readings were taken. This will then allow someone in later years to make the correction themselves if they want/need to.
If all you want to do is to be able to illustrate a new section of passage, then your silva compass and no clino in this case will be fine. Once drawn up, whether using a computer or hand drawn, it will allow people to see what is there. In this case it will not matter too much if the whole thing is swivelled by a degree or two. This should even be OK over multiple trips as long as the same instruments are used, and the same person takes the readings. However it is worth stating what techniques and equipment was used so that future users of the survey know its limitations (this should be done for any survey).
However, if you wish to use the survey for anything more ambitious, such as seeing if what you have found may link to something else for instance, then you really do need to start employing techniques such as compass callibration and just as importantly know where the entrances are in relation to each other. However this takes extra time and effort. Equally the point about adding extra information is quite correct. However if you listen to everyone's idea of what is vital information to take you will spend forever looking for it and writing it down. My suggestion is to note what you think is relevant, as you gain more experience you will note more.
In short go for it. Do your surveying how you want to do it (taking as much advice as you want), but someone willalways complain about what you haven't done! However, surveying is a much misunderstood activity. The perception of boring/cold trips is totally wrong. There are few ways of fully understanding or appreciating a cave/mine than by surveying it and the satisfaction of producing the final map is fantastic. You will learn far more by actually going out and trying things out and making mistakes than by absorbing any amount of reflected wisdom (as useful as that may be).
As to the computer versus hand drafting? I use a computer programme (already mentioned on here so I will not repeat) to generate centreline information, and then hand draft, scan and add text. I know Ouan's work very well (I helped him with some of it) and he uses a fully computer generated method. In Ouan's case the program allows him to add passage detail, and then distirt it with changes to the centreline detail as he is working in long complex systems in asia where trips are made over many years. Oviously if you used my method to do this you would have to redraw the detail after every trip. However most of my work is in short isolated caves, so it is rare that we have to do any redrafting. I would also challenge anyone to suggest that Ouan's presentation is inferior in any way to that produced by hand drafting.