Ambient Light or Speedlights

 Ambient Light or Speedlights

by William Lulow

At my granddaughter’s seventh birthday party recently, I thought I would do an experiment and shoot part of it with ambient light and part with my on-camera speedlight. Many people are just covering events with their camera-phones because it is so much easier than carrying around any kind of lighting equipment. But sometimes, the quality of the images obtained with artificial lighting is just that much better, especially if you intend to make any kind of printed enlargements.

There are many reasons for wanting to control your lighting:

1. You want to light a scene the way you want, not just with the lighting that is there.
2. You want to shoot with faster shutter speeds, smaller apertures and lower ISO settings.
3. You want to make clearer images
4. You want to make larger prints

These are just some of the things you might consider when deciding whether and/or how to light your images. Given the ambient light of the venue, I first made some preliminary exposures and found that I would have to shoot with an ISO setting of 1250 in order to be able to stop my lens down to f/5.6 or so with a shutter speed of 1/100th of a second. (By the way, if you are using an iPhone, it will usually make all these decisions for you. Yes, you can control it manually, but how many of us take the trouble to do it? )

With digital sensors much more sensitive to light than film ever was or that they were say, twenty-plus years ago, using an ISO of 2000 can still yield some great results if you can take some precautions, such as:

1. Put your camera on a tripod or monopod.
2. Steady the camera some other way such as cradling it with two hands.
3. Know how the photographs will be used and determine how sharp they need to be.

Here is a result of some of my ambient light shots. They were all hand held (no tripod) at a fast enough shutter speed to stop most action but they are not “tack sharp”:

These images look fairly good and they are mostly sharp, but not as sharp as I normally would like. If they were meant to be uploaded to a website or used as part of a social media post, they would probably be okay. Details are fairly clear, expressions are readable and there is enough light to make them. They are very different from this shot however:

Look at the clarity and sharpness of this image. It was made with a flash on-camera, bounced into a large soft card reflector aimed at the subjects. The settings were: ISO 100, f/5.6 @1/100th of a second. You can easily see the difference  between an ISO setting of 1250 and that of 100. Everything is crisper, more well lit, and the lighting balanced for daylight exposure. The ambient lighting ones above were made with ISO 1250, f/5.6 @1/100th of a second. This represents approximately a 4-stop underexposure! It’s often difficult to get tack sharp images with that kind of an exposure push!

As a note, I always like to stop my lens down a few stops over shooting wide open because I have found that most digital lenses are sharper if more of the middle of the glass is used. Stopping the lens down to about f/5.6 usually takes care of this.

Using an ISO setting of 1250 in order to get a proper exposure is roughly the same as underexposing a piece of film by the equivalent of 4 f/stops. In other words, in the name of allowing the ambient light to make a correct exposure, you are giving up the clarity and color balance of what you would get from exposing the image “correctly.” We used to do this when we rated Kodak Tri-X film (normally ISO 400 and one of the fastest monochrome films at the time) at 1600 then developed for the underexposure. The images were sharp, but a bit grainy overall. We used to call this “sharpness in grain.” You would excuse the less-than-tack-sharp image because it was grainy but you could “detect” the sharpness. Here is an example:

My image of Elton John shot in concert back in the 1970s, looks pretty good but it’s not tack sharp. Shot with my Nikon 200mm f/4 lens set wide open, with a shutter speed of 1/160th of a second. I set my Pentax Spotmeter to an ISO of 1600, took a reading of the performer’s face and developed the film in Acufine or Promicrol developer. All of the images on the film were exactly like this in exposure and quality, good enough for magazine use. In the early 1970s that’s all we could do, underexpose the film by about 4 stops and then develop it with a fine-grain developer to try to bring out as much sharpness as we could. This image stood up to an enlargement of 16×20 inches but wasn’t as sharp as other images that weren’t “push processed.”

Compare this with a modern digital image obtained under similar stage conditions:

This image of singer/songwriter Mary Fahl, formerly of the October Project, was made in a night club, ISO 2000, f/7.1 @1/125th of a second, camera mounted on a monopod, with my Canon 85mm f/1.8 lens. At this magnification, you can really see all the details of her face, the microphone and even strands of hair. It is much better than the similar shot of Elton.

The moral of this particular story is that if you want really crisp images of any event, you need to consider lighting it so that you do not have the “push” any image’s exposure limits.

With all this said, what I have always tried to do when covering events, is to make the lighting as close as I can to what I can achieve in the studio or even on location with the addition of some artificial lighting of my own. Here are some examples:

A corporate event shot with three lights. Two on stands placed strategically and a “mainlight” mounted on the camera.

This image was made on location with the use of three lights, two placed to the rear of the subject but out of sight, and one soft main light placed on the camera. The reason for keeping one at the camera position is so that the subject will be correctly lit no matter what any of the other lights are doing.

Light is the most important element in any photographic effort, so when first starting to shoot any kind of event (or anything for that matter), make sure you have enough light. Decide on the amount of detail you need to show. Decide how the images will be used and how large they need to be (if they will be printed, say). Then your lighting attempts have a better chance of being successful. If you just go into a situation thinking that the ambient light will suffice, you might have to think again. Remember the “Triangle of Exposure.” If there isn’t enough light to make the images you want, you will need to sacrifice something; maybe clarity, sharpness, or other qualities you may need.