The journal of the BCRA Cave Surveying Group.

Legible versions of the URLs from CP22, and VIP's address

April Field Meet in South Wales - Come Along!

Announcement for this year

Short review of Zecom waterproof paper

Types of waterproof paper

Requesting info on an East German compass

Results of tests to determine the difference between 1st-generation (sequential) and 2nd generation (parallel) GPS units.

Martin has a dream: to have a set of instruments that don't need a tape, string or topofil between stations, and don't need you to get your head in the dirt to take readings. He presents the solutions he has found so far. Is this the future?

Survex v0.81 and 0.90 beta

Winkarst 6.0 released

New Compass Release

CaveTools version 3.0 now available

Mostly an apology for the late arrival of this issue. This is due to your editor taking on too many things at once. I spent most of February editing the Cambridge University Caving Club's 1999 Journal. This (combined with the BCRA science symposium, the CUCC dinner, and a GPF meeting, as well as needed to fix my house and build a workshop/garage) has meant I've been unable to do CP until mid March. We'll try to get back on schedule for the next issue.

Sorry about the font I used for the URLs in issue 22. It was a misguided attempt to get them all on one line, and looked OK on the proofs, but as several of you remarked, it photocopied very badly and was largely illegible in the finished product. I'll not use that one again!

Here are the URLs again (corrected where they have changed since CP22) so that you can look them up if you like.

UTM/Lat-long conversions:

UIS symbols:

Survex:

Tunnel:

CaveTools:

Compass:

David Gibson points out that I forgot the contact details for the waterproof paper review in the last issue of Compass Points... (I should have mentionned them as they gave the prizes for free)

The date is the 10/11 April 1999 at South Wales Caving Club, Penwyllt. It has been organised by SWCC members Allan Richardson, Brian Clipstone, and Iain Miller.

The library will be available for the weekend.

We have negotiated members rates for the weekend, i.e. all CSG members attending the weekend will be charged £1.70/night if they are staying.

The organisers feel it is important to have some pre-arranged activities and aims for the weekend in order to attract people, so the following program is suggested. You are of course free to come along with other things you want to do/test/discuss.

a) The posts are still in place for the instrument tests. In the light of the data from last time we can do some slightly more rigorous testing this time round and get some definitive results.

b) There will be some form of basic surveying training, and some easy areas of OFD 1 will be identified as suitable for beginners.

c) There is the possibility of the use of a diver and Ogofphone to locate a dry chamber in the OFD 1 sump area, this would then need to be surveyed in on the surface. (This is a real project - Weather and Diver permitting). If this particular project is not possible, then it would be possible to use the Ogofphone elsewhere above OFD 1 to obtain accurate surface fixes.

Other attractions will be the opportunity to try out the current range of survey software, and to get advice on the best way to keep your datasets. A discussion on the future development direction of Survex will also be held, so come and have your say.

So, please come a long for a convivial weekend of surveying. We already have a couple of new faces expressing an interest so it should be good. There is no need to book, you can just turn up, although a phone call so we know who to expect might be a good idea.

To be considered for the award, individuals or caving clubs must bring their work to the attention of the judges. For a cave survey, you can do this by displaying it on your club stand at the conference. If, however, you want other work to be considered - such as a report or publication on a surveying topic, or other more general achievements - then you should contact the judges in advance. You can do this by writing to "Hidden Earth 99" at the address below.

The conference is at Leeds this year, from 10th-12th September.

Follow the links to Hidden Earth at http://www.caves.org.uk

Offers of talks, presentations etc. to the Lecture Secretaries:

i) Paul Mann (Expo & technical),

ii) Alan Speight (UK regional),

General enquiries, including Arthur Butcher Award nominations to the Bookings Manager,

The Tunnel effort sounds interesting. The URL was difficult to read, but I did find the site.

I am somewhat curious about what the WeatherWriter survey book is. Not that I ever expect to be using that brand in this country. Your little blurb has me confused because you mention Tyvek laser-printer paper. Tyvek would melt in a laser printer. We have the following kinds of materials:

• Survey books for normal land surveyors have heavy rag paper.
• "Rite-in-the-Rain" (trademark) survey books are the normal heavy rag paper that is treated with a silicone water repellent. I can make the equivalent by spraying an ordinary notebook with Scotchguard (trademark) fabric spray. One of the caving supplies dealers has this made into "Rite-in-the-Cave" books. This takes pencil when wet, but does not erase well when wet.
• Polyester drafting film (Mylar is a Dupont trademark) has a sheet of polyester film with a coating that takes pencil or ink. Ordinary pencil will wash off, but there are special plastic leads that are waterproof. India ink made for drafting film is waterproof. The film is translucent, so you can only use one side and you need to put a white sheet beneath it. This is good for drafting final maps. It might go through a copier or laser printer without melting, but I have not tried it.
• Denril (trademark) is another plastic drafting film. It appears to be a porous polyolefin. It is translucent and not as stiff as the polyester films.
• Dennison, who makes labels of all kinds, made a clear film with a white coating on both sides meant for copiers. If you made erasures on both sides you could get a clear spot. This was discontinued.
• Tyvek (Dupont trademark) is made of non-woven polyethylene fibres. I would be afraid to run it through a copier or laser printer for fear it would melt. It does not take pencil as well as paper, but it can be erased when wet, though not very well.
• Xerox Never-Tear Paper is not paper. It appears to be white (not clear) polyester (?) with a white coating on both sides. I'd make up a book of this if I knew I were going into a really wet and muddy cave. I would use the plastic pencil leads. I just stocked up on this. Two stores that had it no longer have it. I have a fear it is being discontinued after being on the market less than a year.

• One of the European cavers recommended using papers impregnated with a thin polystyrene varnish. This has to be home-made by dissolving polystyrene in acetone. I have not tried this.

Bob Thrun

Yes, the mention of Tyvek was confusion on my part, I actually meant Zecom, as David Gibson points out elsewhere (although VIP do also sell Tyvek paper). Exactly which, if any, of the above materials Zecom corresponds to is not clear.

Dear Editor,

I would be grateful if you would publish the following in Compass Points - unless you are able to answer my questions yourself?

In the December 98 issue of Compass Points, I was intrigued to see the article on Martin Sluka's survey compass with his additional laser pointer. I have just been given an exactly similar compass (obviously without the laser), in order to find out more about it.

The compass is chunky and heavy, being made of metal, but has a quality engineered feel to it. What is particularly unusual is that the dial is back-to-front, in that the graduations are numbered anticlockwise, with East to the left of North, rather than to the right. The dial can be rotated by a screw in the side of the unit, but there is no reference mark on the base of the unit, so there is no obvious way of zeroing the dial. There are no marks for sighting the compass either.

The compass has a number of features. A spirit level, to determine when the compass is horizontal, and an inclinometer. In addition, on the hinge of the lid is a graduation showing the angle of the lid to the base, and another spirit level, which can be viewed from both the side and the under-side. Finally, there is a 7cm ruler engraved on the edge of the lid.

It has only one marking - "Freiberger Prazisionsmechanik, Made in DDR".

I would be grateful to hear from anybody who could tell me more. In particular, why is the dial anti-clockwise, and how is the compass supposed to be used, without zero or sighting marks? Also, how is the lid to be used for measuring angles?

Thanks, Ben cooper.

I have been surveying caves since 1972 - quite a long time. I have used many different techniques to survey, from theodolite to "Romanian method" - topofil and simple compass without clinometer. The first surveying I participated in was theodolite surveying in a very complicated cave with many narrow passages. Hours and hours to wait for making one shot. Real surveying started with an old mining - a heavy box with large hanging compass and inclinometer. You had to stabilise the surveying points, use strong line to connect two points to hang the compass on, and use tape to measure distance.

In 1975 was my first visit to Romania, and I met for the first time cavers who did only exploration and surveying. No digging as was usual in Slovakia, where I'm originally from. Romanian cavers used a very fast method to survey - a simple orienteering compass and home-made topofils. No clinometers; the height difference was simply given as 0, 0.5, 1 m and so on. Not very accurate but fast. They drew the map directly to scale on graph paper. I visited Romanian karst more than 20 times and mapped more than 10 km of caves. In that time friends of mine discovered "waterproof graph paper" - normal graph paper impregnated with polystyrene - the best material for drawing on in caves.

In 1979 I started to use this method in my 'home cave' - Cachtice cave, to re-survey all known areas. The cave, previously surveyed with a mining hanging compass was at that time about 750 m long. After our survey it was more than 3 km long, with almost no digging. We just surveyed all small passages, faults, chimneys, pits ... Subsequently we started to use a simple clinometer, graphical reduction of distance to draw maps in caves, electronic calculator and so on. As you may imagine, the Suunto or any other standard surveying tools you use were absolutely not accessible to us at that time. To obtain simple geological compass from East Germany one had to smuggle it through border and it was really expensive too.

In 1985 we started to survey one very interesting cave in Slovakia - Cave of dead bats. It is more than 15 km long now. I have participated in several expeditions - to Slovenian Alps and to Turkey.

All this time the two biggest problems were that one had to measure distance by topofil or tape, which means connecting two points by line or by tape, and the difficulties of surveying steep shots. My dream from that time was to use a laser beam for this. After quite a long break (from 1989) I started caving again three years ago. Because of the different political and economic situation I was able to realise my old dream - to make surveying tools which do not use any kind of line or tape; and also do not use any kind of optical sight, because in narrow passages, it is very often difficult to see from one point to another. The first step was the compass with attached laser pointer (Figure 2). I found it worked really very well - you may measure very accurately and there is no problem with steeply sloping, or narrow, passages. You may measure from point to point and your eyes do not have to be in line with the shot - very important.

But the problem was how to measure distance. After a couple of experiments with ultrasonic tools I found that Leica made a very nice product, the Disto Basic, a small 'laser tape', with which you may measure 100 m +/- 3 mm. So the measuring of distance was OK too.

Inclination - last problem. In a special shop for surveying tools I found a long digital level, with very good accuracy and simple calibration - the 'incliTronic'. The final task was to arrange these two instruments together with a small spirit level - to measure inclination in the vertical plane and thus ensure the incliTronic is properly aligned (Figure 1 - front cover). I have used this tool on 5 trips, with very good results. The only problem is, that human eyes in dark conditions such as in caves are very, very sensitive to the laser beam. The reflection from mud is strong enough to give a bad feeling in the eyes. So one must be careful.

I think you may survey with these tools as fast as with classical ones, but with much better accuracy and without any problem with steep shots or shots to inaccessible points. You may measure LRUD very quickly and easily, and avens, pitches, and so on.

Specification of Disto Basic: range from 0.45m to 100m, accuracy +/- 0.3cm. It is 23cm long, 7.5cm wide and 4.5cm thick. It weighs 0.6kg with batteries - 4 x 1.5V AA cells. The Disto itself is waterproof with the exception of the battery compartament. You may seal it by silicone cement, but it is not necessary in 'normal cave' conditions.

Specification of incliTronic: accuracy +/-0.1deg (0.3deg), very simple calibration It is 16.5cm long, 6cm high and 2.5cm thick. It weighs 175g with batteries - one 9V PP3. It is necessary to seal the back side of the incliTronic with tape and silicone cement, because of large holes in the cover. But it is a quite simple operation. The second modification necessary is to connect two wires from the incliTronic to a standard 9V battery. Because the incliTronic has its own switch, you don't need to be particularly careful about this.

We use small aluminium plates about 5 cm in diameter as "reflecting glasses" on survey points. These are primarily to allow the user to easily see both the target and the level on the instrument at the same time, using 'peripheral vision'.

The Disto has a timer mode - you hear five beeps and the Disto will measure distance. So you don't need to press button manually, which is good because it is quite easy to move the Disto's laser beam whilst pushing the button on longer shots. The incliTronic has four buttons: ON/OFF, Calibration, Degrees/Percents and Hold. Pressing the Hold button allows you to read the device after you have moved it and with the laser off.

I have tested one digital compass ­ WayfinderOutback, but the accuracy is quite low at +- 2 degrees and it is quite expensive too. Also battery life is very short. I think, the combination of laser pointer and compass from Topofil should be good.

Finally, my 'laser tools' are not for sale, they are much more ideas, what is possible today.

This is potentially serious, so the bug has been fixed and the new v0.81 released. You can download this from:

DOS: http://www.survex.com/software/svx081.zip

Source: http://www.survex.com/software/svxsrc-0.81.tar.gz

This potentially can affect anyone using 0.80, so we recommend everyone should upgrade.

In the light of the response to the 'Proposed changes to Survex' puplishing in CP22, a new release has been made incorporating these changes to put Survex on a sounder footing for future development. The most obvious effect of this is the change of the name of the main data-processing executable from 'survex' to 'cavern' (the 'rn' coming from Network Reduction, this being a major part of what the data processing does).

• Standard output during processing changed so that only lines that cause errors are displayed. This makes it much more obvious when a file was missed in the middle of a long run. The output format is also compatible with editors that understand GNU error messages. This means you can just double-click on the error line to get the offending file loaded in Emacs, for example.
• The above bug writing out the data reduction network is also present in the 0.90 alpha releases up to alpha4 - it is fixed in alpha5 onwards.
• A couple of improvements for UNIX users - Survex is now shipped as an RPM (pre-compiled binaries for i386 systems) to make installation much simpler. Xcaverot has had a bug fixed where it only loaded the first 2048 stations.

The www download page is: http://www.europa.com/~gp/winkarst.html

Thank you for your support, please email any comment or bugs.

Verified to run in Windows '95, '98 and NT. Version 6.0 will not run in Windows 3.1 and has been compiled to take advantage of Pentium class processors (no 386 or 486). WinKarst has been ported to a new compiler with new look and feel to all of its dialog boxes.

WinKarst now remembers a last read files list for easy access to the most frequently used cave surveys. The user can also save plotting preferences.

Improved accuracy. Earlier versions of WinKarst used a numerical technique called "scaled integers" which produced graphics quickly, but created inaccuracies in DXF exports. Now WinKarst uses floating point arithmetic in all calculations and DXF exports are true. With the advent of faster Pentium processors, the performance penalty or using floating point is almost unnoticeable. As a footnote, by directly exporting a DXF view of the cave, the units (feet/metres) are preserved, enabling subsequent DXF update imports as the cave survey grows.

Registration is now required, but is still free for this version only. Future versions will time expire without purchase after a trial period. Registration codes issued for this version will be valid for future updates. The registration code is obtained from the WWW data server, or by email, gp@europa.com.

1. DIRECTX VIEWER FOR STUNNINGLY REALISTIC PASSAGE MODELS. There is now a special new COMPASS program for creating extremely realistic passage models. The program is called CaveX and it uses Microsoft DirectX technology. The program creates very smooth, fully three-dimensional passage models using Gourad shading and a new proprietary technique for rounding passage corners. Passages are realistically shadowed using movable light sources. The models are even shown with perspective so that far passages appear smaller. The passages can be textured with photographs of limestone giving very realistic, rock-like passages. Because of the speed and power of DirectX, the models can moved and animated in realtime. On a Pentium 90 with a fast video card, I get 40 frames per second for small caves and 10 frames per second for larger caves.

There are several images on the COMPASS web page showing the new models.

The program requires Win95/98. If you are using Win95, you must download DirectX version 6.0 from the Microsoft web site. Hardware recommendations are: Pentium class computer, 32 meg of RAM and fast video card.

2. PASSAGE MORPHOLOGY HIGHLIGHTING. The Viewer now has the ability to colour cave passages according to the size and shape of the passage. The program analyses the height, width, and cross-sectional area and can colour passages that fit into various categories. The categories include: Crawlway, Stoopway, Walking, Fissure, Canyon, Tube, Borehole and Climbs/Pits. Colouring specific passage types allows you to analyse the geology, and speologenesis. For example, you can easily see areas where there are vadose canyons or phreatic tubes. You can also pick routes through a cave that avoid crawlways, climbs or pits.

3. MERGING DEM FILES. The DEM reader can now merge adjacent DEM files.

This is useful when the area you are working with is near the edge of a DEM files. It allows you to centre your terrain models on any location.

Files can be merged east-west or north-south. A pan factor setting allows you to centre your merged file location between the two files. You can also centre on corners by first merging east-west files, then north-south.

4. REMEMBERING THE LAST FIVE FILES. All COMPASS programs now save the last five files you used in the file menu. This makes it easy to open recently used files.

There are also 11 other bug fixes and improvements.

• New conversion option now supports direct conversion of COMPASS plot files to 3D shapefiles for visualisation and analysis using ArcView's 3D Analyst extension.
• Registration/transformation utilities now support Z (elevation) specification.
• Registration tools now support any shapefile format cave survey data, including survey data exported to shapefiles using Walls.

CaveTools Version 3.0 is an ArcView extension and requires ArcView GIS Version 3.1 or higher. CaveTools Version 2.0 supports ArcView GIS Version 3.0 or higher.