Accurate Timing of Long Exposures

[Richard Weber]

When shooting in low light conditions with slow film at small apertures, exposur e times can easily exceed one second in many cases. Does anyone know of an effec tive method for accurately timing exposures that exceed one second? I am using C opal #0 and #1 shutters with a cable release. I have tried counting "one-thousan d and one, one thousand and two..., etc) in my head while the shutter was open, which is not a very consistant methodology, as an error of 1/4 second on a two s econd exposure is significant. I've also tried cocking and firing the shutter tw ice at one second exposures each, but that introduces the possibility of moving the camera between exposures. Any ideas?

[David R Munson]

I just time my long exposures with my wristwatch, a Timex of the digital variety. With shorter exposures, I'll just watch the seconds count off until the proper exposure has been reached and hit the shutter release a 2nd time (shutter speed set on T). For long exposures, generally anything exceeding 30 seconds or so, I'll just use the stopwatch function on my watch so I don't have to remember when I started counting. In low light when it's hard to see the face of the watch, just hit the little Indiglo button. I'm sure there are other ways of timing long exposures, but this has worked well for me as long as I've been doing photography.

[Ken Burns]

Richard, you might try counting elephants. "One elephant, two elephants, three elephants," etc. If you are shooting neg film and are worried about inconsistencies, just make sure your error is on the overexposure side. A 1/4 second error on the overexposure side of 2 secs is negligible. Like has already been mentioned, a wrist watch is a good tool to use especially if yours has a timer that beeps. Some meters have a timing device function. My Sekonic 518 does. If exposures get really long, exposure accuracies become less important. If an exposure is, say, several minutes long, a 15 second error won't be all that bad. When I am working in the studio, I often have to make exposures of 15 to 30 minutes. I always bracket by making two exposures, one is twice the time of the other. With exposures that long, it can be difficult to tell the difference between the 15 minute neg and the 30 min neg.

[David A. Goldfarb]

Try using a metronome (an electronic one that doesn't have to rest on a level surface). Set it to 120 and subdivide each beat into two or four. Figure out how many half seconds the exposure should be, and once you've got the rhythm, press the release. Musicians do this all the time and manage to be quite precise (on the order of thousandths of a second).

[Sean Billy Bob Boy yates]

When I shooting chromes in the last studio I worked for, exposures run 30 seconds plus on a regular basis. We used quartz digital and mechanical stop watches purchased at the local hardware store, etc.

[Richard Weber]

I suppose I should have also mentioned in my original posting that I am shooting large format landscapes, so metronomes and the like are a little impractical. The timing issue is generally most critical with exposures between 2-5 seconds, where the "human factor" of inaccuracy is most significant. I suppose without having some widget that would depress the cable release for a pre-set time (yippee! another widget to drag along with me!), the "human factor" will be unavoidable.

[Geoffrey_1456]

Richard,

Prontor makes an interesting gizzmo which has a timer (2-32 sec) attached to a cable release. Linhof sells it for about $625, but you can find a used one for about $25. It should help you with your long timing exposure. Cheers,

[david clark]

Hi Richard, if you are shooting B&W I don't think it has to be all that accurate. In the past shooting at night and at dusk or dawn, If I metered a couple of secs, I'd think, OK somewhere between 2 and 4 sec, maybe shoot one around 2 1/2 to 3 1/2. It might be more critical the amount you cut back on your development so you don't block out details. Seems in the 2-5 bracket half sec more or less didn't seem to me to make much difference, but then again maybe I'm wrong. I don't think I'd opt for the two exposure method, I'd be worried about something moving. Best, David

[Steve Baggett]

Radio shack makes a small (2in x 2in) countdown timer for about $15 that is very accurate (quartz timer). I use one and set it to 2-?? seconds and hit the start at the same time I open the shutter. It beeps when it hits zero and I close the shutter immediately. If it is light enough to see the face of the LCD, I can be "prepared" when zero is near. If it is so dark that I can't see the LCD, the expopsure times are usually >30 seconds and it doesn't matter if I'm a 1/2 second slow on the close, anyway. It has a little clamp that allows me to clamp it to my shirt or jacket. Especially useful for long (>10 second) exposures but still useful for 2-10 second ones.

[David A. Goldfarb]

I shoot large format landscapes and don't find a metronome impractical. Have you seen a modern quartz metronome lately? They are quite small and compact. Not one of those big Seth Thomas spring-wound metronomes (the kind Ansel used in the darkroom to time dodging and burning exposures, incidentally) with the baton waving back and forth or the old Franz electric with the faceted light on top that you need to plug in. You can find an accurate, sufficiently loud, battery operated metronome that weighs about an ounce or two and fits in your shirt pocket for less than $30.