Fritz Pölking,  May 1999: <-back

About Batteries and the Power Consumption of Modern Reflex Cameras

Before 10-12 years ago the modern reflex cameras with autofocus appeared the power consumption of a camera was nothing one talked about. One simply put a small round cell R9 for the exposure meter into a compartment on the lower side of the camera and that settled the subject of energy supply once and for all. The shutter worked with a spring mechanism and the photographer wound the film on manually, rewound it himself and also set the focus manually.

If the camera does no longer work this does not necessarily mean that the batteries are really empty. Most probably one is half empty and the others are still topfull or all of them are 70 - 90% full. The-refore they can still be used without any problem for some time to come in flash, remote release, light meter, flashlight and palmtop functions. With a fair-priced voltage tester (as shown above) you can very easily check the load status of the batteries.The only critical point were extremely cold temperatures since then it could happen that the tiny battery sized just about a pfennig failed. But even that was nothing worth talking abouit with some cameras such as the Nikon F3. When for on-the-spot reports under such conditions you connected the motor - operating with 8 round cells R6 - then these also took care of the power supply for the camera. You could then remove the small round cell R9 and had a 12-volt power supply capable of withstand-ing temperatures however icy they might be.

But when cameras such as the F4 or EOS-1 appeared the matter already looked quite differently: They needed power for the shutter, the display lighting, the mechanic wind and rewind functions and, of course, the autofocus.

The faster the autofocus became and the faster the film was rewound, the more pictures per second could be shot, the more displays supplied more and more information - the higher, of course, was the power consumption. While the Nikon F4 still managed on 3 batteries the F4’s already needed 6 and the new Nikon F5 needs 8 batteries at the very least - and this should be lithium batteries if at all possible if one doesn’t want to replace them excessively often.

In early 1997 when the F5 had just come onto the market you could hear the most fantastic stories about its power consumption - but that had also been the case in the early stage with the F90 from Nikon or the EOS-1 from Canon and its lenses with the fast AF drives.

For the F5 with 8 lithium batteries Nikon now states a useful life of the energy source of 250 films provided that you photograph at 20 degrees centigrade using a 28-70 lens and refocussing it for every picture with the AF. At minus 10 degress centigrade the power is said to last for 70 films.

The display lighting alone uses up very much power. If, for instance, with the F5 one reduces the time of the display lighting per individual function from 16 to 8 or 4 seconds, allows the film to rewind in 4 seconds without motor, yet doing it yourself with the crank, if one refocusses manually and does photograph at a speed of 8 pictures per second, but uses the single-frame mechanism and in addition only uses short times below 1/125 sec. - thus the shutter needs not to be kept open for too long using up power - and if finally the fine focus AF - if you think it to be absolutely necessary - is not activated via the release button (which then ‘energizes’ the entire camera also activating the display lighting) but via the small AF button on the rear side of the camera, then the eight batteries perhaps last even for 500 or 1,000 films...

But that is, of course, mere theory for we have not bought these wonderful tools in order to again photograph like in the ‘stone age’.

My first trip with a (borrowed) Nikon F5 took me in automn 1996 to China. There I had only taken with me some manual lenses and as a result thereof my battery consumption stayed within the warranted standard. I then photographed polar bears at the Hudson Bay in Canada - also focussing only manually - and the battery consumption likewise corresponded to the standard as stated by NIKON. In December 1996 I was (this time with my own F5 cameras) in the Antarctica and in January 1997 in Japan with the snow monkeys. At both locations I worked a lot with AF, yet also with accumulators instead of batteries so that I noticed nothing out of the ordinary as regards the power consumption.

The first unpleasant experiences I had in February/March 1997 for then I worked for the first time with lithium batteries, with AF and with really long focal distances at the F5.

It was in the south of Florida, the temperatures were at about 25-30 degrees centigrade and I was photographing almost exclusively with one and the same F5 body using nearly exclusively the 4.o/600 lens and only autofocus.

After 80 films the battery charge indicator began to flash, nothing doing, and I had to replace the 8 lithium batteries. The F5 of my colleague Jürgen Borris who had been photographing a the same time with the same type of equipment did likewise call for new batteries after about 80 films and I - actually didn’t pay any attention to it at all at the time.

When Nikon for a 28-70 mm lens and the continuous use of the AF indicates a service life of 250 films for a set of lithium batteries then an output of 80 films per set of batteries to me seemed to be quite adequate for the large 4.0/600 mm lens. For it seemed to be quite plausible that the power consumption had to be considerably higher to move the AF unit in such a giant lens.

At home I therefore would have disposed of the eight batteries without any further thought and put in eignt new ones. But here in Florida there was no disposal site - at least none that I knew of - and so I put the used batteries in my hotel room in a drawer to dispose of them later on in Germany.

I then happily continued to photograph with the fresh batteries and this time the battery charge of the F5 indicator started flashing only after 125 films with the camera going on strike. Now I had one of my - rare - glorious ideas: I marked this second set of batteries - and now also the first one - because my curiosity had been aroused: Why is it that under alike conditions I once get 80 and a second time 125 films out of one set of batteries? This I wanted to look at closer later on at home in Germany... But the best was still to come: The third set of fresh and new lithium batteries revolted already after ten films.... I thus marked this set of batteries as well and put in the fourth one which then lasted until the end of my stay in Florida.

Thus in the four weeks in Florida I had used up three sets of lithium batteries for about 250 films (that’s what I thought then) with a fourth set loaded. Since such a battery after all does cost 6.00 - 7.00 DM about DM 150.00 alone of the overall expenses for a working trip were spent on batteries and I swore to henceforth only take along accumulator elements which had served me so well in the Antarctica and in Japan with snow and ice.

Three weeks after my return I finally managed at home to attend to the allegedly - according to information supplied by the F5 - used up battery sets. The voltage tester said the following:

1st set of batteries empty after 80 films: All eight batteries were charged 100%.

2nd set of batteries empty after 125 films: All eight batteries were charged 110%.

3rd set of batteries empzty after 10 flms: Seven batteries were charged 110%, one battery was 50% full.

The reason why the third set of batteries ceased to operate already after 10 films is now clear: One of the batteries obviously had a defect of fabrication or was for any other reason 50% empty after only 10 films.

First intermediate conclusion:

When the camera signals that the batteries are empty then one should not necessarily believe it, for that a set of batteries is too expensive these days. Therefore do by all means check first.

The following trips showed that with the Nikon F5 using a 4.o/500 mm AF or a 4.0/600 mm AF lens as a rule one set of lithioum batteries sufficed for 80 films. But thereafter the batteries were still 80-90% full. Obviously our modern cameras do simply turn off when the voltage is no longer 12 volts, but only 11 or 10 volts. Thus the most important finding is that the batteries are by no means empty when the camera says they are but can subsequently still be used for quite some time in electronic flashguns, remote releases, light meters or flashlights. For that it is naturally of advantage if you buy equipment all working with the same type of battery.