ELECTRONIC CAMERA TRIGGERS IN NATURE PHOTOGRAPHY

By J. Mundell (Area 22).

My camera set up for nature photography consists of Praktica equipment and I have a BC1 & 2 Bx20 cameras with bellows, motor drives, right angle viewfinders, Benbo tripods and Sigma lenses from 28mm to 500mm Mirror lens including a 90mm macro lens and modified Jessops TBZ flash guns.

Some two years ago I needed some form of remote camera triggering device to operate the camera at a distance of some 15 meters to photograph some foxes near my home. I decided to make an infra-red transmitter & receiver, and for the transmitter I used a handheld unit similar to a TV unit but with only one button and powered by a small 9v battery, the receiver had a normally open relay on the output and housed in a metal box.

My Next problem was how to trigger the camera shutter and motordrive as both the BC1 camera and the motordrive do not have any facility or a remote lead to construct an electro-mechanical device to operate the cable release function on the shutter release button. This took the form of a modified car starter solonoid, modified to take one end of the cable release, and a small printed circuit board with thyristor output to drive the solonoid, and a timer circuit so as to enable the shutter to fire only once, which would then re-set and be ready to fire again after about 2 seconds. The solonoid & P.C.B. were mounted in a plastic box with cable release, coming out of one end.

A bar was made up to take the camera & motordrive with the shutter release unit mount on the right hand side and the infra-red receiver on the left hand side, this assembly was then mounted on a tripod.

Power to the shutter release and infra-red unit was a bank of NICADS made up to 12v, mounted in a plastic box, and left on the ground. This system has worked very well for some 18 months and gave no problems in the field so far, and is still in regular use.

The one shortfall of the above system is that there has to be a clear line of sight between myself and the infra-red receiver with no obstructions, which led me to design a radio control system to use instead of the infra-red system.

This radio control consisted of a simple one channel transmitter and receiver with relay output, and crystal controlled to hold a tight frequency band. The transmitter is a small hand held unit, again the size of a TV remote control, with a single button to operate. The range is in excess of 100 meters. I have used this to photograph birds and Squirels. The receiver is mounted on a bracket next to the camera, as the infra-red system described earlier with the electro-mechanical trigger unit.

I have just finished constructing a infra-red beam transmitter & receiver, two of each to use as automatic triggers. The system works as a beam unit and the camera is triggered when the beam is broken, i.e. when photographing a Badger or Rabbit leaving their holes, the infra-red transmitter is set up on one side and the receiver is on the other side about 2 meters apart, the camera is focussed on the hole, and when the Rabbit or Badger leaves the hole the beam is broken which fires the shutter on the camera.

Two of these infra-red systems can be used together, to photograph for example, a 'Pond Skater' above the surface of a pond. The idea is to select a spot on the pond and set up both systems, so as the beams cross at the spot where the photograph is to be taken, then when the 'Pond Skater' goes to this spot, both beams are broken and fires the camera shutter. This allows complete control of where the photograph is taken and the subject will be in focus.

A lot of my outdoor photographic work is done with flash, and I use two Jessops` TBZ guns, modified so as to use one power pack feeding two guns, this gives me faster recycling time down to half a second, up to 700 flashes before recharging.

These flash guns do not have variable outputs and as I need to cut the power down E.G. on close ups, I obtained some square ND filters of various strengths and cut these down to fit on the front of the flash guns in the filter holders, to give various power outputs i.e. 3/4, 1/2 & 1/4.

This then is a description of my trigger units that I have built & use, and if possible at the 1991 A.G.M. I will be there with my equipment and demonstrate its use.

In the future I hope to write another article going into full details of how the equipment is set up and used. And perhaps another article.