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Can someone please help answer this quiz question?
You are outside photographing a night shot of the Tower Bridge in Old Sac with a camera on a tripod. You want to catch the lights of the bridge and the streaks of the cars passing by. Your camera will only read an exposure down to a shutter speed of 1 second. You really want to have an exposure of 1 minute when you use a shutter release cable to keep the shutter open. If the exposure is 1 sec at f/2.8, what is the f/stop exposure at 1 minute (not including reciprocity factor)?
The instructor said we can get help on the question. I should taken my butt out night to find out the answer, but I gotta turn my quiz in an hour. lol
You are outside photographing a night shot of the Tower Bridge in Old Sac with a camera on a tripod. You want to catch the lights of the bridge and the streaks of the cars passing by. Your camera will only read an exposure down to a shutter speed of 1 second. You really want to have an exposure of 1 minute when you use a shutter release cable to keep the shutter open. If the exposure is 1 sec at f/2.8, what is the f/stop exposure at 1 minute (not including reciprocity factor)?
The instructor said we can get help on the question. I should taken my butt out night to find out the answer, but I gotta turn my quiz in an hour. lol
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Sacramento
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Re: Can someone please help answer this quiz question?
Sun, March 19, 2006 - 1:25 PMLord knows I'm far from being an expert on any of this, since I'm just really starting out myself, but a great book I'm reading now on night and low light photography said, if I am remembering correctly, that often, if you set the aperature quite small to maximize the depth of field, the camera will actually keep the shutter open a lot longer than it's got actual settings for, at least if you're working on aperature priority.
I don't know that this actually answers your question, though. What did the answer turn out to be?
Wendy -
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Re: Can someone please help answer this quiz question?
Wed, March 22, 2006 - 5:14 PMFor each second you elong the exposure you are dropping down another stop . The thing is 1 sec . to 60 seconds is a big jump !! You probably don't have that kind of latittude on your lens . That said it sounds as if your prof was giving you a trick question !! 2 seconds would be f4 etc etc . soooooo the thing is you have to figure out what is ok to blow out and what do you want to still retain detail !? -
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Re: Can someone please help answer this quiz question?
Mon, January 29, 2007 - 9:18 AMI wasn't totally clear there. Each time you double your time you make an extra stop ie. 1 -2 sec 2-4 sec 4-8 sec 8-16sec 16-32 sec 32-64 sec. That is a six stop step . Digital sucks at long exposures so watch out for that as it gets real noisy .
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Unsu...
Re: Can someone please help answer this quiz question?
Thu, September 7, 2006 - 5:07 PMinvest in a handheld light meter...it means no more math! well, maybe a little math after you get past f/64 or some tiny aperture like that.
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Re: Can someone please help answer this quiz question?
Mon, October 30, 2006 - 10:08 PM__1___ @ ISO?= ___60___@ ISO?
2.8 ?
This is the mathematical formula for finding out the ISO recipricity is a third less ONLY in film.
Basically this is an algebra question.... the missing fact is 1 sec/2.8 at what ISO?
