The
Belfry
Bulletin
THE JOURNAL OF THE BRISTOL EXPLORATION
No. 39
1950
September
Starting Cave Photography By D.A. Coase This article is intended to help those members whose first attempts at Cave photography have not been too happy, and who may, perhaps, therefore have become discouraged, or blamed their cameras for the failure to get good photographs. This is not usually justified, as any camera which will take good pictures out of doors (that means any camera, in fact) can be used for cave work. Perhaps it should be explained here that the more expensive and more complicated cameras are designed to enable a wider range of subjects to be tackled than is possible with the simpler models, and for this reason are essential for some cave shots as they are for certain open air subjects. In many cases cameras with expensive wide aperture lenses have to be ‘Stopped down’ to give the required depth of focus, which immediately puts them on an equal footing with the simpler cameras. We shall therefore assume that you have one of these simpler cameras, and that you are sufficiently experienced in its use to turn out reasonably good photographs out of doors. If you feel that you are not, then, then a few rolls of film used in getting to know your camera, and a shilling or two spent on one of the many excellent little books now available will be well worth while. In going through this process you will almost certainly find that there are some things that just cannot be done with your camera, and the same limitations will, of course, apply with equal force underground. Therefore don’t waste film or invite discouragement by trying to take photographs that just can’t be taken with you apparatus - keep within its limitations and it won’t let you down. To sum up, any camera can be used for cave photography, provided you know how to use it, and exactly what it can’t be expected to do. With regard to films, there is perhaps now even more choice than many of us were accustomed to before the War, but with this difference, that the brand one is used to can’t always be obtained. It is therefore almost a counsel of perfection to suggest sticking to the film you always use, but if you can do so, it will be found well worth while. If you haven’t a favourite film, either Verichrome or Selochrome will be found as good as any to start with, as they are specially made to cope with slight errors in exposure, and are quite ‘fast’ enough for most purposes. For lighting there are several methods which have been used, but the commonest and one of the cheapest is undoubtedly flash-powder. This can be bought in small quantities of ½ or 1 ounce, and should be mixed used carefully according to the instructions printed on the packet. You must be particularly careful to keep both the powder and the touchpaper dry, and your own ingenuity will no doubt suggest a suitable method of doing this - you'll be wanting a container for the camera which can be relied on to keep water and mud out, in any case, and of course you’ll need something to light the touchpaper. If you can carry it, (or, much better, persuade someone else to carry it) you will find a tripod very useful, as otherwise you may hay have some difficulty finding somewhere really suitable to put the camera for the shot you want to take. A tripod also helps to keep the camera clean, as well as holding it quite steady during the actual exposure. In taking a cave photograph, the usual sequence of operations is 1. Choose the Subject; 2.Put the camera in position; 3. Put the flash in Position; 4. Open the camera shutter; 5. Fire the flash; 6. Close the shutter; 7. Wind on the film; these are dealt with in order as follow: -
BB39/2 1. Choice of Subject. This is obviously a matter of personal choice and can include formations, passages, chambers and cavers in action. For a start you will be well advised to leave out people and concentrate on the smaller chambers – the ‘Old Grotto’ in Swildons is quite useful and to practise on anything much larger may introduce more complications than necessary, as also may mean anything much smaller. 2 .Choice of Camera Position. This is one of the more difficult problems, as a cave floor is usually far from level, and almost invariably dirty; a tripod is a great help at this stage but an awful nuisance to carry around. On the other hand, there are often ledges of rock or loose boulders which can be pressed into service. Normally you will want the major object (or person) somewhere near the middle of your picture, and you will find that tilting the camera up or down to, secure this can give marked distortion which is rarely pleasant, as stalactites usually hang vertically and look better that way in a photograph. Remember too, that unless you have a focussing adjustment on your camera, you should not put the camera nearer to the subject than about 12-14 feet, or the picture is sure to be ‘fuzzy’, and for the same reason try to avoid anything in your picture space much nearer than your main subject. For cave work, the type of view finder usually fitted to cameras will be found of very little use: - you will be very fortunate if you have a direct vision frame type finder, or can get one fitted, as the only practicable method of working with the more usual ‘brilliant’ finder is to persuade a ‘stooge’ to wave a torch around so that you can judge where the edges of your picture will come. If all else fails, simply point the camera in what you hope is the right direction and await results. While setting up the camera be particularly careful not to put your hand too near the lens, nor to breathe on it, or it will be clouded over by a film of condensed water, which may take quite a long time to clear in the damp atmosphere of a cave. To complete setting the camera, fit a lens-hood adjust the ‘stop’ or aperture of the lens. On most box cameras and the simpler folding ones, this is already fixed by the maker, and may be taken as f/16, but if yours is variable, set it to the position marked f /l6 or ‘bright’. The stop fixes the amount of light passed by the lens, and consequently the amount of flashpowder you will need to get a properly exposed picture. 3. Placing the Flash. When placing the flash, quite, apart from any consideration of the amount you are going to use, which we’ll deal with later, you will need to take two things into account. Firstly, make sure that there is no odd stalagmite or body which will cast an unwanted shadow on your subject, and secondly you will want the light from your flash to fall in the right direction to give the effect you are after. Volumes could be (and have been) written on this subject, but the old advice to have the flash slightly above and behind the camera, and a little to one side continues to hold good for all but the most ‘dramatic’ effects, and the time for ‘stunt’ lighting is after you have learnt to take reasonably consistent photographs with this well-tried set up. Especially if you have no lens-hood, you should be especially careful that no light from the flash can reach you lens, either by placing a tin, or a small piece of rock or even; a colleague in the way. When everything else is ready, measure out your flashpowder on to a spare tin lid which you have kept dry for the purpose. The quantity of flashpowder depends on the film, the stop used, and the distance between the flash and the subject, and since the film is assumed to be Verichrorne or Selochrome, and the stop f/16, the amount to be used may be taken from the following table, and should be right for normal cave scenes, but if the walls are very dark, double the quantity, or halve it if they are very light, (i.e. covered with white stalagmite). QUANTITY OF JOHNSON’S No. 2 .FLASHPOWDER REQUIRED IN GRAINS FOR ‘'CHROME FILL 3c’ Sch AT f/16. DISTANCE FLASH TO SUBJECT (in Feet) GRAINS OF FLASHPOWDER
5 12
10 30
15 56
20 80
25 30 40 110 150 220
Such a table can only serve as a rough guide, and if you find that your negatives are consistently too thin (under-exposed) you should use more than the amount of powder indicated, while if your negatives are too dark, decrease the quantity. For measuring out the flashpowder, the makers used to issue small scoops holding 10 grains, and if you can scrounge one of these, your problems are solved, if not, you may be able to
BB39/3 borrow one and copy it. Failing this, you will find that 10 grains of flashpowder is just about the maximum quantity that you can pile on to a sixpence. When you have measured the powder, insert the piece of touchpaper, which, of course, must also be kept perfectly dry. Sprinkling a little powder part of the way up the folded touch paper makes the operation more certain, while drying the touch paper in front of the fire before the expedition may also help. For the same reason, don’t put out the flashpowder until you are ready to use it, and always keep the tin tightly closed. 4. Open the shutter after you have made quite sure that there are no lights in front of the camera. Use the Time setting of the shutter (marked’T’). Then 5. Light the Touch Paper and wait for the flash to go off. Be particularly careful only to light the touch paper and not the powder, and to keep your hands (and face) well away from the flash. If the touch paper goes out, when you are quite certain that it really has gone out, try a fresh piece, which is much safer than trying to relight the old one. 6. Close the Shutter then, 7. Wind on the film, and you are ready to start all over again, Now a few general points. A cave is a wet place and very soon gets misty with water vapour. If you are going to get wet, try to take your photographs before you do so, if this is at all possible. Otherwise, work as quickly as possible without rushing things unduly, and avoid smoking until you’ve got your picture. If the cave has a natural draught, try to arrange the order in which you take your shots, so that the draught blows the smoke away from your next subject. Don’t forget that you are still caving, so must observe the usual safety precautions. You need at least one other person with you, and he is liable to get rather bored with the proceedings unless he also is a photographer. In the latter case, it is quite possible to set up his camera at the same time as yours and take two views of the subject with the same flash. Well, that is the story, so now it is up to you to have a go, I’d be interested to see any results you get, and if I can help with any advice, or by answering questions, then I’ll certainly do my best. D.A.COASE **************************************** Photographic Competition. It has been decided that as a year’s Belfry Subs. is not useful to all, an alternative lst. Prize of TWO years’ Annual Subscription would be offered. T.H.S. **************************************** Notice of London Section Meeting. The next Meeting of the London Section will be held at 32. Montbelle Road, New Eltham, by invitation of Monty and his wife, on Sunday, September 24th. Report on the London Section Mendip Meet. 1950. The London Section again invaded the Belfry in force during the week or so that preceded the August Bank Holiday. It had been hoped that the major item on the agenda would be to finish off the Stoke Lane survey, but in the event, the really keen types were not able to be there all at the same time, and the amount of rain which had been falling during the previous weeks had made Stoke even less inviting than usual. In an admirable burst of enthusiasms, a load of gear, including the compass was taken to the sump early in the week, ready for the survey party, but was forced to remain there until the Saturday of the Bank Holiday weekend, when there was a dual purpose trip. This did complete the data for a centre-line survey of the parts of the cave beyond the sump, and also one or two photographs which are worth seeing, apart from the usual proportion which art not. D.A.C. chose this trip for some experiments with colour film, and it may be said that some of his transparencies have to be seen to be believed. Not so the remainder.
BB39/4 The previous evening a small party of the L.S. was able to secure permission for a photographic trip into the upper series at Wookey Hole, and here again results were largely not up to standard owing to over optimistic views taken by certain flash-bulb manufacturers as to the light output of their products. Warning to others here.. . . take these figures with a few grains of salt, or preferably flash-powder. The chief protagonist of flash powder succeeded in burning his hand with some and a Johnson flash-gun in Bowne’s Hole, though the injury was unexpected rather than serious. On the same afternoon a general tour of the known swallets of the Stoke Lane area was undertaken by six of the party under the general guidance of a certain ex-RAF type who now assists in the making of maps to mislead people who prefer to use this method of finding their way. The gent's navigation on that afternoon is going to take some living down. Other expeditions included a little Swildons, a G.B. (mainly photographic); an Ife Hole (mainly pornographic} and several Hunters (mainly paralytic). Comments so far received from the now re-dispersed L.S. indicate that they, at least, had a very good time, and typical is the remark of one member who wrote that he had done more caving that week than during the whole of the rest of the year put together. It looks as though we shall be coming down again next summer. W.J.S. ************************************ The editor has recently received several suggestions that the Belfry Bulletin should be enlarged. To enlarge the BB is not quite so simple as it sounds. Firstly more material is needed, and this is the chief editorial worry. Secondly the production dept., who spend a lot of their spare time working on the BB would have one third more printing to do for each extra page. The third factor, that of extra cost is for the time being a debatable one, but will shortly become less important as our expenditure in other directions grows less. An interesting point is that some of those who have made this suggestion have never sent in a line of any sort for inclusion in the BB, but are always super - critical of those few who are pulling their weight. If you want a bigger BB, and the production Dept. are willing to have a bash, it's up to you; send in more material and you will get one. ************************************ List of Members 1950. No. 6 Ken Dobbs, Omar Taylor, Derek Wood, Tony Bamber, Miss Margaret Pope, Mrs Betty Shorthose, B.A. Walker, Mrs. Jean Collins, H. Tearks, Miss Daphne Weeks Jack Waddon John Mason, W.A. Montgomery, Ron Gollen, Dennis Chadwick,
55 Broadfield Road, Bristcl. 4. c/o Mrs. Lyon, Carmangary, Henderson Street, Bridge of Allan, Stirlingshire. 113 Congre Grove, Filton Bristol. 135 Hornby Road, Blackpool, Lancs. 42 Filton Grove, Horfield, Bristo1.7. 26 Gateside Road, Upper, Tooting, London.SW 17, (BALham 545). 76 Willoughby Road, Langley, Slough, Bucks. c/o Leigh House, Nempnett, Chew Stoke, Nr. Bristol. Webbington House, Loxton, Somt. 164 Sylvia Ave., Knowle, Bristol. 4. 7 Haydon Road, Taunton, Somt. 77, Hamlins Lane, Exeter, Devon. 32. Montbelle Road, New Eltham, London, S.E.9. 58, Harrowby Road, Grantham, Lincs. 63, West Cromwell Road, London, S.W.5. **************************************
A Weekend in South Wales. by John (Menace) Morris. The other weekend Don Coase dragged me off to Craig-y-nos, and the Friday night found us at the S.W.C.C. cottage chasing the mice that had used Don’s sleeping bag as nesting material. After a reasonably early breakfast neat morning we set off for Ffynnon Ddu.
BB39/5 I didn’t know quite what too expect, but I was really surprised at the size of the place. To warm up, we did some delicate climbing up into some of the higher passages. Then we went to attempt the ‘stream’ passage. Stream!!! I was horrified at the foaming torrent. Don said it was impossible to try to go on. However it thought it would be possible to get at some phreatic passages about 60 feet above the stream. We had 120ft. of Alpine line with us, so we roped up and arranged a complicated system of fixed handline, belays and lifeline and organised ourselves into the firm of Ropework Colossal & Co. Ltd. To my rock-climbing mind, struggling on dripping, rounded stalagmite bosses over a raging torrent seemed rather horrifying but Don seemed to enjoy it. We eventually reached the higher system and commenced to crawl, squirm and curse our way through it; every now and again we had imposing views of the stream 60ft. below. At one pointing a particular tight bit, there was a fierce and horrible torrent of oaths from Don, who had caught his hair on fire. The smell was really grim, and Don seemed quite peeved that I should find it so funny. Then while I was in the lead I found a muddy pipe which had never been tackled, so off I went with Don right behind. Then came to the worst z-bend I had ever seen, lined with mud and half with water, and in which I had to revolve three times. I could see the passage getting bigger beyond a boulder and after a terrific struggle I became badly stuck and also in a panic as I couldn’t breathe properly, so we had to retreat. We eventually got back to the cottage, having had a wonderful day. I would like to say how well the South Wales Caving Club entertained me and that I appreciate it very much. J.V. Morris *************************************** The Magpie Mine, Nr. Bakewel1, Derbyshire. by Pong Wallis. Recently a visit was arranged to explore the Magpie Mine nr. Bakewell. Geoff and Leslie Thompson, John & Michael Buxton & I met at the entrance at 10.30 to be confronted with a formidable barricade of timber and wire and a large notice ‘Danger – Trespassers will be prosecuted’. Nothing daunted, we changed and set off up the tunnel, a drainage channel or ‘sough’. For the first 20 yards we were able to keep clear of the water by walking on an old set of tram rails, but when these ended there was for it but to get in up to the waist. The mass groans testified to the coldness of the water, but we continued up a fine tunnel about 8ft. high and wide and walking along a sandy floor beneath the water which was flowing strongly against us. A strong draught blew in our faces. We continued thus for about ¾ of a mile, though for the latter half the water gradually got shallower and was no more than knee deep, but of course we were thoroughly chilled in our legs by this time, so its main effect was to make walking easier. Towards the end, a path had been built up to one side of the tunnel and we were able to get out of the water completely. We sat down thankfully in a small chamber and emptied our boots and wrung out our clothes and then set off to explore. The first feature that struck us was the profusion of calcite crystals everywhere, and everyone collected some very fine samples of dog-tooth. A large number of passages were explored, but all ended at a blank wall, so the water was followed for a further ¼ of a mile or so until a high narrow rift was reached. Somewhere hereabouts is the bottom of a 600ft. shaft, but all the passages which seemed safe to explore again led to dead ends, so the search was abandoned and we returned to our depot and ate lunch before once more immersing ourselves in the water. The trip back was much quicker as we now had the current with us, but we were very glad when the cry of ‘daylight’ was heard. From the entrance to the foot of the shaft is about 1⅛ miles, but the passages did not go quite straight, so that all told we must have explored the best part of two miles of tunnel. There is very little crawling to be done as most of the passages are 6ft. or more in height; but one section of about ½ a mile involved bending over somewhat as the roof is about 5ft. it is rather tiring on the back.
BB39/6 There is very little dripstone to be seen, but the quantities of calcite crystals is very large and very good specimens can be found. The mine is at present being re-opened for working and further passages may be made safe in the near future and more exploration becomes possible. R.M.W. AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA The editor has received a letter from J.M. Tompsett who asked that it should be printed in the BB. This letter has been passed on to Ted Mason, but we have not yet received his reply. The full text of the letter together with Ted’s reply will be printed in BB 40. $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ Club Annual Dinner. We had hoped to include the final gen on the Dinner in this BB, but at the time of going to press this has not arrived. We hope however to include and insert which will give you the details with this issue. Failing this each member will be notified as soon as possible. T.H. Stanbury £££££££££££££££££££££££££££££££££££££££££££££ T.H. Stanbury, Hon. Sec. 74, Redcatch Road, Knowle, Bristol. 4. W.J. Shorthose, Hon. Sec. London Section B.E.C. 26, Gateside Road, Upper Tooting, S.W. 17. H. Perry, Acting Librarian, 20, Northfield Avenue, Hanham, Bristol R. Cantle, Leader, Climbing Sect., 46, Cherrington Road, Henleaze, Bristol. 7.