Twilight is a magical time.

Just because the sun is down, doesn’t mean you should put away your camera.

When the Sun sets, a different looking world exists for photographers.

Colors don’t appear the way they do in daylight.

Instead, colors display based on your camera’s white balance setting and how that setting matches the various light sources in your scene.

Backgrounds become less distracting.Street lights and lit building interiors give you outlines and shapes of various colors.

An online friend, Jane Lyons, was kind enough to share her wonderful picture of the New York city skyline.The exposure info from metadata: ISO 1600, aperture f3.5 on automatic. On automatic, the camera doesn’t tell us how long the shutter speed was. What’s impressive is Jane’s composition and also how well her Nikon 40DX exposed for the scene on auto. I don’t know if Jane used a tripod. My guess is, she must have since this is a vertically image. Try steadying your camera for a vertical picture without one, and you’ll know what I mean. Note if the low clouds were not in the picture, this wouldn’t have been as nice. The clouds add a visual interest by reflecting the colors of the city lights. Nice Job, Jane!

Chances are not everything in your scene is lit.

So what you see in your viewfinder is very close to what you’ll get if you expose carefully and properly.

People in your scene don’t matter as much unless you want them to.

Passers-by don’t register in your image. Even if they do, they are a blur unless you “freeze them” with a flash.

Cars show up as trails of red and amber lights. Skies take the color or aura of the city’s lights especially if there is a medium like condensation in the air to reflect it.

Compared to other subjects, night photography doesn’t require a whole lot of equipment. The following are necessities:

• A steady tripod
• a cable release to trip the shutter. Most people can get by using the self-timer. The key is to not shake the camera when you trip the shutter.
• a flashlight to illuminate the knobs and dials of your camera.
• optional–a portable flash with lots of batteries

For a class exercise, I timed the duration it took one of my students to drive once around the parking lot.
Based on that time of 10 seconds, I figured out we needed to set the aperture at f22 for ISO 200. I fired the flash by pushing the open flash button at the car when it approached the right. Note to self: next Spring when I try this again, I need at least 3 more students to help me paint the scene. Also I should ask the student driving to pause and hit his brakes a little more to get more red tail light trails.

In a way, photography at night can be easier than during the day.

You pretty much will get what you see in your viewfinder.

You don’t have to worry about trying to light anything except when you want to include a person in the picture. But I’ll discuss that later.

The various elements in your picture lights itself freeing you to just concentrate on your composition and exposure.

I photographed the Petronas Towers in Kuala Lumpur, Malaysia last July (2007). I had a few minutes to hastily grab this picture. Purists would argue that buildings don’t tilt backwards like that. Instead verticals should be verticals. That would mean I have to find another skyscraper and take this picture from high up so that I’m keeping the building on the same plane. ISO 100 f8 @ 1.3 seconds with a 17mm lens. Architectural photography is very specialized and a Tilt-and-Shift lens is essential to counteract this tilting back effect called “keystoning.” Such a lens (Wide Angle Tilt TS-E 24mm f 3.5) costs in the neighborhood of $1,200.

Fountains tend to have spots and colored lights on them, christmas trees are never displayed in public without multicolored lights and beautiful majestic architecture in most civic centers are usually brightly lit up showcasing a city’s pride.

Here’s how to set up:

1. Change the ISO on your camera to 1600 or whatever the maximum number is.
2. If you have a digital SLR, attach your longest focal length lens on your camera and take a light reading. The idea here is to use the narrower field of view so that your lightmeter can give you a more accurate light reading. If you have spot meter reading mode on your camera, that will give you a similar result.
3. Calculate your exposure for ISO 200 based on the reading you get in step 2. See special note on calculating exposure
4. Note the exposure. Switch lenses to a wide angle or even a more “normal” focal length lens and compose your shot.
5. Tighten all the axes on your tripod head so that your camera doesn’t move in during the exposure.
6. Finally, set the camera to the self-timer mode. Some cameras give you a choice of 2 seconds or 10 seconds. The whole idea is, you don’t want to jostle the camera when you press down on the shutter. Let the camera settle on its own and 2 seconds ought to be enough for that.

Calculating Exposure

Making your camera’s CCD or CMOS more sensitive to light makes it easier for you to get a light reading. If you leave your camera’s ISO at 100 or even 200, your meter might not register a reading especially if the scene is something lit only by moonlight.

Remember that there are always 3 components to exposure. ISO, aperture and shutter speed. For the sake of our discussion, let’s say when you pointed your camera in step 2 at the scene, your meter recommends 1/15 sec at f 2.8 ISO 1600.

If you haven’t read this yet, then just take my word on this. High ISO settings yield images that are extremely noisy. That’s the equivalent of grain in the analog or film world.

So what we’ll do next is figure out equivalent exposure at say ISO 200.

ISO	F-Stop	Aperture	Shutter Speed	Notes on exposure
1600	0	f 2.8	1/15 second	Recommended exposure by camera
800	1 stop	f 2.8	1/8 second	Decrease ISO by 1 stop to 800. To compensate, increase shutter speed by 1 stop to 1/8 second
400	2 stops	f 2.8	1/4 seconds	Decrease ISO by 1 stop to 400. To compensate, increase shutter speed by 1 stop to 1/4 seconds
200	3 stops	f 2. 8	1/2 seconds	Decrease ISO 1 stop to 200. To compensate, increase shutter speed by 1 stop to 1/2 seconds

How did I arrive at a shutter speed of 1/2 second for an aperture of f2.8 when I switched the ISO from 1600 to 200?  ISO 200 is 3 f-stops less sensitive than ISO 1600.

There are 2 ways for me to do achieve equivalent exposure. Let’s examine the first method which entails leaving the aperture the same at f 2.8 and only changing the shutter speed. That means I’m only increasing the time the shutter stays open, allowing in more light by the same 3 f-stop factor.

Now that you have your exposure for an aperture of f 2.8, let’s say your subject has some depth and you want to be sure more of it is in focus. You can figure your exposure by changing the just the aperture, leaving your ISO the same at 200.

Let’s say you decide you want make your picture at f11 giving you more depth-of-field. You again have to increase the time the shutter stays open in the same ratio or f-stop to get the equivalent exposure. F11 lets in 4 stops or 4 times less light than F 2.8.

Now our exposure is going into the full seconds.

ISO	F-Stop	Aperture	Shutter Speed	Notes on exposure
200	0	f 2.8	1/2 second	Recommended exposure by camera
200	1 stop	f 4.0	1 second	Decrease aperture by 1 stop to f 4.0. To compensate, increase shutter speed by 1 stop to 1 second
200	2 stops	f 5.6	2 seconds	Decrease aperture by 1 stop to f 5.6. To compensate, increase shutter speed by 1 stop to 2 seconds
200	3 stops	f 8	4 seconds	Decrease aperture by 1 stop to f8. To compensate, increase shutter speed by 1 stop to 4 seconds

The second alternative to achieve equivalent exposure, opening the aperture to let in more light, is not always practical because I would be restricted to using my “fastest” lens, a 50 mm f1.4.

Even that lens has physical limits–it’s widest aperture is f 1.4. The resulting image would still be underexposed by 1 stop. I would need to buy a 50 mm f 1.2 lens. Have you priced one of these? Canon makes one for about $1500.

If you have a tripod, you have the luxury of dropping your shutter speed without worrying about camera shake.

That is often your best option because you really don’t want to be making pictures the whole time at your widest aperture whether it is f 1.4 or f 2.8. At those apertures, focus is critical since the depth-of-field is very shallow.

If you happen to set up on a pedestrian bridge and people are working on it as you are making the exposure, then you might have to wait for a lull in traffic.

Getting Fancier–Painting with Light

Once you’ve mastered the intricacies of figuring out exposure, you are ready to include a person in your pictures. Remember people are likely appear as a blur during long exposures even if you tell them to stay still.

So a combination of painting them with a portable flash is the only sure way to have good images of people in night photography. If you’re on your own, you’ll have to trigger the camera by remote or using the self-timer.

If in our example above, we calculated that we will use ISO 200 aperture at f 11 and shutter speed at 1/4 second.

First, we’ll set the self-timer to 10 seconds. Next, we set our flash to ISO 200 as well. Then we set the flash on automatic to give an output of light equal to f 11.

Rehearse in your mind how and where you want to run around in the picture as you fire your portable flash 10 seconds after you press the shutter button.

Remember the shutter will stay open for 4 seconds, so if you move during that exposure, chances are you won’t register at all in the final picture.

If you require more time to complete your painting with light, you can close down the lens some more from f 11 to even f 22. Now to achieve equivalent exposure, you’ll lower your shutter speed to 8 full seconds.

Why would you do that?

• The batteries in your flash may not recycle to full power quick enough, so the added 4 seconds might give you another burst of flash.
• Your subject’s motion, which you are trying to capture, requires more time.
• You need more time to move around the scene to paint other important elements in the scene.

Photographer Eric Curry has a show at UC Riverside’s Museum of Photography using this very technique of “painting with light.” Go see the exhibit, get inspired and then…

Go out there and have some fun especially on the next full moon. You’ll be pleasantly surprised by how much light there is at night in our cities.