Light Meters – the most essential tool for perfect exposure

Today’s digital cameras can almost achieve ideal exposure results easily, though in many cases they are not so good. The introduction of TTL metering saw the massive decline of the use of one photography’s most important tools, the Lightmeter. For the majority of photographers especially the younger generation have only ever-used digital capture and never cut their teeth on film. Those were the days where if you got it wrong it was wrong, there’s no checking the image on the back of the camera, you had to wait to get your slides back from the lab or waited with baited breath in your lab at home. I learnt on film and relied heavily on a light meter to get the exposure correct, a skill that very few of the new generation know or understand. Most do not realize the most important part of photography is light.

Right – My trusty old Sekonic L-508 Zoom Master has been my constant companion for nearly 20 years. I regard it as the most important part of my gear and an essential tool for my work

The ability to master a light meter can save so much wasted time in the field and post-production time in front of the computer, it is an essential tool and will also make you a more efficient photographer, once you master it you will feel lost without it. The advent of digital made lazy photographers, many believed the light meter was a thing of the past, many just begun checking back of the camera after the shot, the more attuned ones checked the histogram and others just believed in the flexibility of shooting RAW to fix the exposure. But all of this takes time, and this is something that I don’t possess. Getting the exposure correct, results to the closer I can come to getting away from the computer and back behind the camera. Understanding correct use of the light meter will make you a successful photographer.

For me my trusty old Sekonic L-508 Lightmeter is my constant companion to get spot on exposures correct first time every time. I work in a studio everyday and acquiring exposures correctly for my product work is paramount. Most professionals will use them, have you ever watched the fashion shows like Americas Top Model or Double Exposure? If not, watch them and see that many photographers’ still use light meters to get the shot right every time, though these shows can be just downright boring TV they do have some good points when the photographers are the main subject. Almost 99.99% of photographers will never work in a studio so the requirement for a light meter seems irrelevant but if you are an avid landscape photographer it is a bare essential piece of equipment.

Left – the classic sunset scene, if the camera recorded this scene then the foreground would under expose by up to 3 stops. By metering the foreground then balancing the sky with a ND hard grad the scene is balanced. This cannot be achieved with the in camera meter. Gear – Leica M TYP 240 with Zeiss Biogon T 28mm f2.8 ZM and Lee RF 75 filter system.

As I use many systems and multiple formats of cameras, one thing is very relevant is that not all cameras measure the light the same. If using TTL all will have register different exposures and record an image as they see it and not what your eyes see. Out in the field the difference between my Nikon D3, D3X and D800E is astounding at times, and then throw in my Leica M9, MTYP240 and MM and then its even more mixed up, they are different but all respond correctly to the settings acquired from the Sekonic. These cameras may need some fine tuning, as an example the meter readings I get from the Sekonic are 100% perfect for my Leica M TYP 240, it records exactly to the meter. The MM will over expose a bit but this is a different camera and one should underexpose this camera normally. The Nikons are similar, the older D3X is perfect, the D800E, needs to be precisely metered most likely due to the super high-resolution sensor, taking multiple readings, then averaging them out works the best for this camera.

Light meters aren’t hard to use, especially Sekonic, they come with a manual that unlike many electronics nowadays that come with a bible, Sekonic’s is so basic that the basic functions can be mastered in minutes. When looking for a Lightmeter the most important part is that it needs to have several functions so it can be used in all lighting situations you may encounter. Look for a meter that has a reflected, incident and flash mode, all these serve different functions.

Reflected Mode

All camera meters are programmed to a scene in middle or 18% grey when the light strikes the subject. Where they get tricked or fail is with high contrast tones, like snow, it will calculate the exposure so that it will make the snow appear middle grey, thus underexposing the subject. In the opposite case lets say a black cat, typically the camera meter will overexpose the picture because it assumes the cat is grey. The main reason why a camera meter fails is they don’t read a very small portion of the image. In TTL mode they use about 15% of the image to record the exposure and even in spot mode, they read 3% to 5% of the scene, this is not accurate enough to take reading in many circumstances. A handheld meter reads the light in one degree or 0.5% of the composition. Thus you can choose the portion of the picture that you have identified as middle grey and obtain an accurate reading from it.

In reflected mode, first identify a middle-toned area of the scene and point the meter at that area, position the viewfinder’s target circle over the middle-toned area then click the record button to take the reading, the correct f-stop/shutter speed combination for proper exposure will appear on the meter’s LCD. The accuracy of Sekonic’s meters will record within a tenth of an f-stop. So a typical exposure reading as an example would look like f/8 + .7 or f/8 and 2/3rds. If you want to use a different lens aperture or shutter speed than the ones displayed for more depth of field or creative blur a moving subject, simply rotate the main dial or press the arrow buttons on the meter to see the f-stop/shutter speed combinations that will achieve the correct exposure.

Right – Snow is terribly difficult for cameras to expose as they record the white snow as 18% grey thus under exposing it dramatically. In reflected mode you can accurately record the snow without under exposing it or blowing out the highlights. Gear -Leica M TYP 240 with Super Elmar – M 21mm f3.4 ASPH and Lee RF75 filter system

Reflective mode is the best for landscape scenes. Multiple exposure readings can be recorded then balanced out with grad filters to attain the perfect image. With all landscape images I use Lee Filters, especially ND graduated filters. These allow you to balance the sky and foreground to attain perfect exposure. Simply record the foreground exposure and the sky, then calculate the difference between the two, then you can select the correct ND grad required attain the correct exposure for a balanced image. In the camera you set the exposure manually for the foreground and then balance the sky with the appropriate grad. Voila a perfect landscape image, it’s that easy.

Incident Mode

Cameras do not have an incident-metering mode. It is a function that is available in handheld light meters and is worth every cent you pay for the meter. In incident mode, the meter records the light via a white hemispherical dome, it measures the light falling onto your subject, instead of measuring the light reflected from it as in reflected mode. Incident mode meters the light before it hits the subject, so really it doesn’t matter if you are recording light or dark subjects.

To use the incident mode, select it and then hold the device in the light that is falling on the subject. If you and the subject are both in open sunlight, you can take a reading from where you’re standing, near the camera. However, if you are standing under shade cover and your subject is in direct sunlight, then you must meter next to the subject so that the meter detects the same level of light that is falling on the subject.

Above-Incident mode is perfect for portraits. Metering the light falling onto the subject attains perfect exposure for the face and you can be creative and adjust for exposure to under or over expose the back/fore ground for artistic expression. This shot was metered and shot with the Leica M9 and Noctilux wide open, at 0.95 there is a huge chance that you will get the exposure wrong, but with a light meter it will give you the correct settings. Gear – Leica M9 with Noctilux-M 50mm f0.95 ASPH

When you are taking an incident reading from the subject’s position, the white dome should face the camera lens, not the light source. This ensures that the light strikes the dome exactly as it is falling upon the subject. So if you are photographing a face that is side lit, the light must hit the meter from the side just like the subject’s face does. By positioning the meter correctly, you will allow it to calculate the exposure correctly, regardless of the colors or the reflectivity.

Above – Incident mode is ideal for even low light shots out in the field. Early frosty mornings with plenty of fog can play havoc with a cameras metering but but using the incident function on your light meter you get perfect exposure. Gear – Leica M TYP 240 with Noctilux-M 50mm f0.95 ASPH.

You can tweak the exposure for artistic purposes by changing the angle of the meter to the light source and you can easily get a reading for slight underexposure by angling the dome toward the light. Incident mode can’t be used when you’re photographing backlit subjects, like a glowing sunrise or sunset sky or any situation in which the light can’t fall on the dome of the meter when it is pointed at the camera, for this you have to use reflected mode.

Flash Mode

Most handheld meters have a flash meter. If you are using studio flash then this is an essential feature and just as important for location shooting outside with speed lights or portable flash units. Simply put you cannot run or use a studio without one. The meter is able to detect the flashlight, and calculate the perfect exposure.

Left – metering for flash out in the filed is easy, meter the background then fill flash the foreground with the same settings by adjusting the flash power. You dont want to push the flash to far as a little bit of light shadow creates a bit more depth and character. Gear – Nikon D800E with Zeiss ZF.2 Distagon 35mm f1.4 and Nikon Sb900 flash

After you set the flash mode, set the desired speed or aperture required, place the dome next to the subject, click the flash sync button on the meter and then fire the flash. The meter measures the flash, and the LCD registers the camera setting, that is it, pretty simple! You can take both incident and reflected readings of a flash, though incident readings are perfect.

Out in the field for fill flash of people it’s even easier. Take a reflected meter reading of the background, remember this exposure then set the flash mode on the meter and set the desired aperture and speed reading from your previous measurement, then adjust the flash power to suit. Once the desired flash power setting is calculated then you will have shadow less studio quality images in the field. Also by under or over exposing the background/foreground you can create more artistic imagery.

End Thoughts

There is a whole generation if not two generations of photographers that have never used or understand how or why to use a light meter. It’s a pity because we are now in a generation of young photographers with the attitude that we’ll fix it in Photoshop later. The simple addition of a light meter and understanding how to use it eliminates the need to fix it later. I’ve seen many over the years on field shoots with me and training days firing off shows like a machine gun hoping to get one that’s right, this is just a waste and shows lack of knowledge and a sad testament of our lazy society today. I shoot everyday and having many years of experience and always relying upon a light meter I know I can go out and get the shot first time every time.

Right – Deliberately under exposing the back ground and filling the foreground with flash is a great method for dramatizing an image. I shot this image in NZ for Globeride’s clothing division, it was set up and shot in a matter of less than two minutes, this type of image cannot be achieved quickly without the aid of a light meter. By underexposing the back ground it allows the colors to saturate and become more dramatic, then by filling the foreground with three Nikon speed lights at full power illuminates the angler, thus creating an image with more depth and emotion.Gear -Nikon D3X with 70-200mm f2.8 VRIIand three SB900 speedlights

Remember photography is all about light, get that right and everything else falls into place.

There are multiple companies that make light meters, always buy the best that you can afford. I’ve always used Sekonic and as a testament of their quality my L-508 Zoom Master is about twenty years old, its been dropped from a second floor onto concrete, rained on, submerged in mud, sand, dust and snow, its survived temperatures from arctic minus 17 to the blazing heat of 45 plus in the outback, and has millions of frequent flyer points from its global travel, yet still works to this day. I have no need to update it as it still works flawlessly everyday in the studio or out in the field.

Sekonic light meters are available from all professional camera stores