A Beginner's Guide to Expedition Photography

Dave Horsley

My only qualifications for writing this article are that I'm a novice photographer and took photos on the 1997 Expo. I'm not going to give a detailed "How to do it" guide because I'd probably get it wrong from memory and the information is available from one of the many good books on Cave Photography (see bibliography). I used the photography Chapter from Caving Practice and Equipment to find out details like how to work out the f-stop from the distance between the subject and the flash guns and the guide numbers of the guns.

The basic equipment I used was an old manual SLR, a cheap second-hand 28mm (check) wide angle lens and two second hand electronic flashes, with the largest guide numbers I could find. I used slaves bought in pieces from Dave Gibson and assembled for me by Mark Fearon. The slaves were fired by a small flash on the camera, which I covered with a piece of exposed film. This blocks most of the visible light, but allows the infra-red through to fire the slaves. The advantage is that this reduces the chances of reflections off dust and moisture being directed into the lens and minimises fogging in the pictures. I also had access to a number of large flash bulbs for lighting the large passages we expected to find, but made very little use of these as I had problems with acquiring working bulb guns second-hand. (Most seem to take a non-standard size of battery that is no longer made, so they need fettling to take a sensible battery. There are details in Chris Howes' book and CREG journals on how to convert them). I carried the whole lot in an old ammo can, though these can be a problem as the lid can spontaneously open (usually when dangling from the end of a cowstail at the top of a 30m pitch).

My best pieces of advice would be to go on a few photo trips with an experienced photographer if you can (this usually isn't a problem as they are always looking for mugs to help out). This gives you some practical experience of how others set up shots, the gear they use etc. More importantly it lets you experience how easy it is to get cold and bored during long photo trips, then you know what your helpers are going through and don't take too long over every picture. Have a go with your gear on at least a couple of trips in the UK, so that you get an idea of the results you get. This allows you to fix any errors before the all important Expo photos come back as half frames (all beautifully exposed and focussed, but only half there) because you have used the wrong shutter speed for synchronisation with the flash. Also you can get at least a feel for the different lighting effects achieved by varying the flash position.

On the Expo I managed a couple of photo trips in mainly horizontal passage, I usually took 3 or 4 shots of each picture at various f-stops usually varying by a whole stop between each, which may have been a mistake, as very few were ideally exposed, but I did usually get a usable slide from at least one of the four. What I found hardest was focussing (I usually focused on the flame of a carbide) and framing the shots as I could see sod all through the view finder. Just have a go and see what you get.

Bibliography

• Caving Practice and Equipment, Ed. Dave Judson
• Images Underground, Chris Howes, 1998
• Cave Radio & Electronics Group Journals, Ed. Mike Bedford
• Flash slave instructions, David Gibson