Sekonic L-758DR & DTS V3.0 - Professional Photographer Magazine

THE GOODS: PRO REVIEW 

Can this light meter and calibration software help you 

hit the optimum exposure every time? Yes, it can. 

BY STAN SHOLIK 

Dynamic ranger 

SEKONIC L-758DR AND DTS V3.0 

All images ©Stan Sholik 

Can a light meter make you a better photographer? 

If your meter is a Sekonic L-758DR 

and you use the free Digital Transfer Software 

(DTS) V3.0 calibration program, the 

answer is yes. 

Achieving optimum exposure by using 

your digital camera’s built-in meter, histogram, 

or blinking highlights is impossible. 

Among camera makers in recent years, 

there’s been a trend in biasing the autoexposure 

settings (e.g., program, shutter priority, 

and aperture priority) toward underexposure. 

Current DSLRs deliver darker files 

(including files in raw format) than older 

models to avoid getting blown-out highlights. 

That renders images with a lower 

signal-to-noise ratio than necessary, which 

the current cameras compensate for with 

improved and more aggressive noise reduction 

algorithms. 

In addition, the automatic settings don’t 

know, for example, whether the reflection 

off a car bumper should or shouldn’t be held 

with detail, so just in case, the overall exposure 

is lowered to do just that. The blinking 

highlights and the camera’s histogram are 

based on the camera’s interpretation of 

the JPEG produced from a raw capture, 

a poor representation of the actual raw 

data present. 

Setting the exposure manually can solve 

these problems, but without knowing the 

dynamic range of your camera’s sensor, 

you still won’t know if you’re making the 

optimum exposure. The optimum exposure 

places all the scene’s exposure values 

within the dynamic range of your camera’s 

sensor. The optimum exposure also places 

all the scene’s exposure values that you want 

to reproduce in proper relation to other 

scene values within the clipping points of 

your sensor. 

No digital camera gives you the information 

you need to produce the optimum exposure. 

As with your monitor, printer, and 

scanner, your camera’s digital sensor needs 

to be calibrated to ensure that it produces 

accurate, consistent results. The Sekonic L- 

758DR light meter and its associated DTS 

V3.0 software provide the tools you need to 

calibrate your camera for ISO accuracy as 

well as the limits of its dynamic range and 

clipping points. 

After calibrating the meter and Nikon D3s camera, I shot a test outside my studio. The incident light 

meter reading was 1/320 second at f/8. In reality, even though the image on the camera LCD indicated 

a completely blown out sky and overexposed shadows, this is the final uncorrected capture. Lightroom 

showed only the brightest areas of the clouds to be clipped. 

CALIBRATION PROCESS 

The fairly easy calibration procedure takes 

15 to 30 minutes. To get started, you need a 

test target. The accessory Sekonic Exposure 

78 • www.ppmag.com


Shadow Spot Reading 

Highlight Spot Reading 

Averaged Reading 

Using the L-758 spot meter, I measured the darkest area of the trees and the brightest areas of the clouds. In the scale at the bottom of the meter’s LCD, 

it shows where these readings fall relative to the limits of the dynamic range and the clipping points determined during the calibration, shown by small 

triangles. The meter averages the readings to place them within the clipping points. The adjusted exposure shows the reading within the clipping points on 

the shadow side and right on the clipping point on the highlight side. 

Profile Target II is the easiest to use. You can 

also use the less expensive Sekonic Exposure 

Profile Target or an X-Rite ColorChecker 

Classic. After measuring and recording the 

incident and reflected light readings (they’ll 

be different, but the test procedure also calibrates 

your meter to make future readings 

identical) and performing an in-camera 

white balance, you photograph the Target II 

chart in your camera’s raw file format. You 

need one exposure at the incident light reading, 

one that’s three stops underexposed, 

and one that’s three stops overexposed. 

Load these captures into your raw image 

processing software (I use Lightroom 4.1), 

perform a white balance, and output the 

three files as TIFFs or JPEGs. After connecting 

the L-758 to your Mac or Windows computer 

with the supplied USB 2.0 cable, load 

the image files in the Sekonic DTS software. 

The software quickly analyzes the data 

and creates a chart showing the sensor’s 

dynamic range for that ISO setting, with 

clipping points based on Sekonic criteria for 

highlight and shadow clipping. I found these 

points somewhat conservative, particularly 

for the Nikon D800E, so in later testing I 

manually adjusted them closer to the dynamic 

range endpoints. You can also adjust the 

dynamic range endpoints to set them to the 

dynamic range of your output media (fourcolor 

lithographic printing, for example). 

Measuring your digital sensor at one ISO 


accurately calibrates it for that ISO only, but 

you needn’t calibrate it for every ISO. By calibrating 

the sensor at its lowest native ISO 

and one other, such as ISO 400, the DTS 

software combines the two readings to produce 

calibrations from ISO 3 to ISO 3200. I 

did this for my Nikon D3s. It’s quick and the 

results seem accurate. 

When you’re satisfied with the calibrations, 

upload them from the DTS software to 

your L-758 meter. The meter’s memory can 

hold three calibrations; more memory would 

be nice, as Sekonic recommends separate calibrations 

for daylight, tungsten, and flash 

because the sensor response is different for 

each. If you use only one camera model, 

then one calibration in the meter for each 

illuminant is sufficient; however, most of us 

use several models. 

Does calibrating your digital sensor really 

make a difference? If you are a studio photographer 

and have total control over your 

lighting, the most important part of the calibration 

is probably calibrating your meter 

and sensor to the ISO setting of your camera, 

as it’s unlikely you’d exceed the dynamic 

range of your camera’s sensor unless your 

lighting was extremely high contrast. It 

would certainly help in that situation, however, 

to know the upper and lower limits of 

areas where detail is held. 

For photographers shooting on location 

in lighting conditions they cannot control, 

calibrating the sensor with the L-758 meter 

and DTS software makes a big difference. 

For landscape and wedding photographers 

who constantly deal with high-contrast situations, 

it seems essential. 

TESTING PHASE 

After calibrating my D3s for multiple ISOs, 

I went outside my studio to shoot a test. I 

wanted to hold detail in the shadow areas of 

the trees and in the distant clouds. The incident 

meter reading from the calibrated L-758 

was 1/320 second at f/8, ISO 200, and I 

captured an image at those settings. On the 

camera’s LCD, the entire sky was blinking 

red and the capture was very overexposed. 

The D3’s meter wanted an exposure of 

1/640 second at f/9 to eliminate the overexposure 

in the sky. 

Saving the reading from the L-758 (1/320 

second at f/8) as my base exposure, I used 

the meter’s spot meter to measure the 

shadow area of the tree, which fell well 

within the underexposure clipping range 

indicated on the meter’s calibration scale. 

October 2012 • Professional Photographer • 81


To perform the digital camera sensor calibration, load and align the test chart captures in the Sekonic 

DTS program. 

When I measured the cloud, however, the 

meter indicated that it was beyond the highlight 

clipping point of the sensor. Pressing 

the averaging button on the meter produced 

a suggested exposure of 1/400 second at 

f/8.2, and I made a capture at this exposure. 

The camera LCD still indicated a completely 

blown-out sky. 

After loading the captures into Lightroom, 

sure enough, the brightest part of the 

clouds in the initial setting of 1/320 second 

at f/8 exposure were shown as clipping but 

not the entire sky as suggested by the camera 

LCD. Opening the capture in Lightroom 

with the adjusted exposure of 1/400 second 

at f/8 showed no clipping in the clouds. 

Now I could make a further highlight 

adjustment without losing the actual tonal 

balance in the clouds. Detail in the shadow 

areas of the trees was still good, as the meter 

had indicated. 

Getting the exposure right during digital 

capture is essential to producing the highest 

image quality. Using the Sekonic L-758DR 

meter and DTS software to calibrate 

your camera sensor can ensure that captures 

make maximum use of your sensor’s 

dynamic range, producing the lowest signalto-noise 

ratio and highest image quality 

without resorting to post-processing. 

The suggested retail price of the Sekonic 

L-758DR is $634, and the accessory Exposure 

Target II is $132. ■ 

After the DTS software analyzes the test charts, it produces a graph of the results. This is the graph for 

my Nikon D800E at ISO 100. The dynamic range is 7.2EV from -3.8EV below the middle gray exposure 

to 3.4EV above. I found the clipping points at -2.5 EV and +2.6EV to be too conservative, so I manually 

adjusted them closer to the limits of the dynamic range. 

Stan Sholik is a commercial/advertising 

photographer in Santa Ana, Calif., 

specializing in still life and macro 

photography. His latest book is “Lightroom 

4 FAQs” (Wiley Publishing).

Sekonic L-758DR & DTS V3.0 - Professional Photographer Magazine

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