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Caves of Castleton - 3d Survey Project

Moose

Moose

New member
Graham,

This is true, but not at anything like the kind of accuracy that we wanted.

The elevations are correct to less than 1m therefore it's possible to see 'shadows' within the contours where roads and walls are for example.

 
graham

graham

New member
Interesting!

I rather suspect that data is far more accurate (or should I say "precise" or both!) than your survey data which will need a helluva lot of tweaking if it's to match up properly.

I'd be fascinated to see the result.
 
Ouan

Ouan

Member
Moose said:
We are now using Arc View as the GIS mapping software for the project which unfortunately cannot be downloaded free for all to see.
Click to expand...

Hi

As well as ArcView ESRI have written ArcReader which is a free download which lets you view maps (.pmf files) that have been created in ArcView.

 
Moose

Moose

New member
As well as ArcView ESRI have written ArcReader which is a free download which lets you view maps (.pmf files) that have been created in ArcView.
Click to expand...

True, ArcReader is for veiwing a special type of PDF map document, called a .PMF (ArcPublisher Map Format) file. The down side of this is that these are created using a very expensive 'add in' to ArcView as far as I'm aware.

I'd really like to 'share' the output of the GIS work with whoever is interested as we do with the survex 3d models, but it doesn't look as though that's possible at the moment. Unless soemone knows something I don't.

For simplicity I think we're going to keep a live, up to date map (or series of maps) in Arcview and simply PDF publish them (with version numbers) every time we make additions and want to let other people see. It?s the easiest option at the moment.
 
footleg

footleg

New member
Moose said:
The bad things about it for distribution purposes is that I'm not able to use survex as the end format for the overall project as it cannot cope with the amount of information associated with the terrain data. FYI the amount of data is the x,y,z coordinates for a 5m x 5m grid over an area of 7.5km x 4km.
Click to expand...

One possibility is to reduce the horizontal resolution of your terrain data for use in Survex. You can still retain the improved accuracy of your source data compared to other free elevation data, but reduce the amount of data to something more manageable by Survex. I have used a mesh of 20m x 20m grid spacing over a 4km x 4km area for a Matienzo system and that works fine in Survex. It looks even better in the Therion model viewer. I'll be demoing this in the DistoX/Paperless surveying session at Hidden Earth for those who are interested.
 
graham

graham

New member
Except for "show" purposes, those pdf's were, to me, a bit useless. It was pretty difficult to see any detail and impossible to move them around. Now, I know that wasn't the point and I know that the project's owners will be able to gather a lot of useful detail from the original model, but in terms of sharing with other users, they don't work as well as the lower-resolution-but-viewable-in-Aven type of thing.
 
S

Scud

Active member
The re-survey of Peakshole Sough and Wall Shaft Mine is nearly complete and will be forwarded over shortly.
 
Moose

Moose

New member
Footleg is spot on, it's very easy for us to down size the amount of information we make available for import into survex. Extracting either a smaller area directly above a cave system (or part of it if it's large) or by reducing the cell size to say 20m x 20m will enable us to go down the survex route. What's great is that we know it's going to be within 1000mm of being 'bob on'.

What would be really great is if survex was capable of handling any amount of data from a terrain point of view but it's not a GIS mapping program, yet!

As for the .pdf's, yep, they are probably totally useless for the user who wants to zoom in, out, enquire and generally study the drawing as you can with a .3d file. They were made just to illustrate the type of accuracy a 1m contour GIS map with caves embedded within, looks like in 2d.

If there was a way of freely sharing the views that Arc View can produce I would be delighted.

Ultimately I can see the GIS mapping of the Castleton area including aerial photography draped over contours, geological structures layered and obviously something better than just a line to represent the cave passages.

There's a place for survex but there's also a place of GIS mapping software, trust me!
 
Moose

Moose

New member
The re-survey of Peakshole Sough and Wall Shaft Mine is nearly complete and will be forwarded over shortly.
Click to expand...

Good stuff, I will insert it just as soon as I get it.....
 
Moose

Moose

New member
For those who are interested I've added the work on Peakshole Sough as well as the unnamed shaft on New Rake that the TSG were digging.

Also there is a sizeable .pdf file of the ArcView survey model work I've been working on for the whole of the Castleton area.

Both can be accessed by going to:

http://caving.hucklow.org/castleton_survey/
 
Pitlamp

Pitlamp

Well-known member
On 3rd August Moose wrote about the possibility of some of the Peak water resurging in Pindale (which I've only just noticed). There is an article submitted for the next TSG journal which includes comment on this idea. Yes I agree it's distinctly possible and this is one reason for the interest in digging the terminal choke in Peak's Styx Inlet Sump. The present end of this is out beyond the far side of Cavedale in a blank area of limestone. It's also why folk have been working in Pindale Cave in recent years. Neither project is particularly easy but the potential is very good.
 
Goydenman

Goydenman

Well-known member
I still think it worth pushing the Pindale sough into the mine. The mine is likely to have intersected natural. The sough was dug open and a very wet section (up to your chest) led through to standing height in drier conditions where water came from a blocked passage, easy dig, but the air was bad.
 
Moose

Moose

New member
Some effort has been put into surveying in Nettle Pot and the work has been added to the model. The link remains the same.

Also a start has begun on entering LRUD data to the database, this can be viewed by hitting the 'passage tubes' button.
 
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