Sekonic Digital Master L-758DR Light Meter
Claimed as the world’s first multi-function light meter with exposure profiling and wireless triggering, the Sekonic Digital Master L-758DR has been designed for professional photographers who shoot with advanced digital cameras but can also be used by photographers who shoot film. No light meter we’ve encountered offers such a wide range of capabilities. . . [more]
Claimed as the world’s first multi-function light meter with exposure profiling and wireless triggering, the Sekonic Digital Master L-758DR has been designed for professional photographers who shoot with advanced digital cameras but can also be used by photographers who shoot film. No light meter we’ve encountered offers such a wide range of capabilities.
For starters, it’s the most sensitive meter on the market. Reflected flash values can be measured down to f/2, while the incident light metering range extends from f/0.5 to f/161.2. Ambient light levels from EV-2 to EV 22.9 can also be measured. Claimed measurement accuracy is within +/- 0.1 EV. No built-in camera meter can cover anything like these ranges.
In appearance, the L-758DR has many of the features of a traditional hand-held meter, with a translucent dome (known by Sekonic as the ‘Lumisphere’) for measuring incident light and a 1-degree spot viewfinder for analysing reflected light. The viewfinder is dioper-adjustable, although not over a huge range. When the Lumisphere is retracted, which is done by rotating a surrounding, knurled ring, the sensor can be used for measuring individual light sources or flat artwork. The extended position is ideal for measuring three-dimensional light sources. Shifting from retracted to extended is fast and straightforward.
Buttons on the front panel switch the power on and off, select between average and brightness difference (contrast) measurements, access two independent ISO settings, select mid tones and clear the internal memory. The mode button below these is used in conjunction with a jog wheel to select the measurement mode from ambient, auto-reset cordless flash, cord flash and wireless flash options.
A rotating dial around the viewfinder eyepiece selects between incident and reflected metering modes. The measurement button sits just below this dial. The Memory button, which inputs user-defined settings, is located below the viewfinder lens on the side panel. A built-in USB port below the Memory button allows the L-758DR to be connected to a computer for data transfer and so users can download firmware upgrades.
In many ways, the L-758DR works like a traditional meter, combining four different types of metering: Ambient, Incident, Reflected and Flash. But unlike most meters, it can simultaneously analyse and display values for flash and ambient light with a single press of the measurement button, enabling photographers to assess the correct balance between different lighting types. Meter readings are displayed in three ways on the data LCD:
- Combined flash and ambient light readings;
- Readings showing the percentage of flash in the total exposure;
- Simultaneous display of analogue values for flash, ambient and combined readings.
Because measured values can be memorised and retained in both reflected and incident measuring modes, users can measure a midtone value (for example) in a scene in incident mode, memorise it then switch to reflected spot mode to measure highlight and shadow values. This makes it easy to view where each set of values will fall in the subject’s brightness range before the shot is taken.
A built-in light in the L-758DR’s viewfinder can be switched on to illuminate a data display that provides information on the luminance values detected, aperture value (in f-number, EV or an averaged value that indicates subject contrast) and exposure compensation or calibration compensation, depending on the selected mode. The LCD contains a full data set, which varies, depending on whether still photography or cine mode is selected. An analogue scale along the bottom of the screen displays measurements as apertures or EV values with indicators for memorised and averaged values. Dynamic range and clipping point indicators can also be shown on this scale.
Where the L-758DR really stands out is in its ability to ‘profile’ the sensor of a digital camera and use this profile to provide precise exposure control. Profiles from up to three different cameras can be stored in the meter’s memory. This function is necessary because different camera sensors respond to light in different ways. Not only do CCD and CMOS imagers have different characteristics, even sensors from the same camera model can have ISO values that differ by up to about half a stop. They can also vary in dynamic range as well as the points at which they start blowing out highlights and blocking up shadow details.
Profiles for up to three cameras can be created, with different profiles for flash and ambient lighting and incndent and reflected metering.
Fortunately, unlike film shooters, who have to test every new emulsion batch they use, digital photographers only have to run one set of profiling tests for each camera. And, although image sensors may change over time, by the time tonal shifts would become noticeable, most photographers will have moved on to newer equipment and technologies.
Exposure parameters that are measured to produce a camera profile include sensor sensitivity (which is used to calculate how much the camera’s exposure system deviates from the meter’s standard exposures), highlight and shadow clipping points and the sensor’s dynamic range. With these measurements, the L-758DR provides a common standard against which all these exposure characteristics can be compared for a wide variety of cameras – digital, film and cine.
To use the sensor profiling function, photographers must purchase the optional Sekonic Exposure Profile Target (RRP $116.40) and set it up under the lighting conditions they plan to use. Before creating an actual profile the solid grey side of the Profile Target is used to create a Custom White Balance value for the camera sensor under the same lighting conditions that will be used for profile testing. This provides a reference colour value for future calculations.
The patch side of the Sekonic Exposure Profile Target is used to capture input data.
Separate profiles should be created for ambient lighting and flash because camera sensors react differently to them. The test procedure is straightforward – but far from quick. First, a series of preliminary shots of the patch side of the Profile Target are taken with exposures ranging from +7EV to -7EV in 1EV steps. If your camera can’t support that exposure range, try for at least +/- 5 EV steps. For flash exposures, set the lens to about f/8 and make sure the flash recycles fully before each exposure.
These test shots are opened in editing software, which is used to measure the median exposure level of the green colour channel. This data is transferred to the photographer’s computer, where Sekonic’s Data Transfer Software automatically evaluates the entered test data and creates a compensation data table.
Compensation values are created with the aid of the software.
The data table is then uploaded to the meter via the supplied USB cable and automatically calibrates the meter for the specific digital camera sensor and camera settings. A printable table is also available.
A printable data table is also available for each profiled camera via the software.
Ideally, photographers should produce two profiles at different ISO sensitivities (for example ISO 100 and 400). With both sets of data, the Sekonic software can automatically calculate the ISO offsets for the entire ISO range (from 3 to 8000).
Data input from two ISO settings is used to calculate the ISO offsets for the entire range from ISO 3 to 8000.
Exposure profiles for flash and ambient lighting and incident and reflected modes can also be input independently and the meter can be programmed to alert photographers when a measured highlight or shadow area is at or beyond the dynamic range of the sensor. User-defined clipping points can also be registered to provide additional exposure control.
Blinking pre-exposure warnings are displayed on the analog scale on the meter’s LCD to alert photographers to potential loss of highlight or shadow detail. And, to provide additional fine-tuning, the midtone adjustment button on the front panel of the meter can be used to shift the exposure to favour either highlights or shadows when the subject brightness range exceeds the dynamic range of the sensor. This function enables photographers to prioritise exposures to record detail where it is required in each shot.
Pressing the memory button after taking a light reading sets a mark on the analogue f/stop scale on the lower edge of the LCD panel, making it easy for users to see how many measurements have been stored. Up to nine readings can be memorised in incident or spot metering modes simultaneously in both Aperture Priority and Shutter Priority Modes.
As expected for such a complex device, Sekonic has provided a high level of customisation for L-758DR users. Fourteen parameters can be pre-set to a photographer’s specific requirements, including the following:
- Users can select from full- half and 1/3-step increments in both shutter speed and aperture.
- The memory and measure buttons are switchable.
- Compensation adjustments can be set to preference subtractive or additive settings.
- The jog wheel can be set to increase or decrease selected values when the wheel is turned clockwise.
- Dynamic range and clipping point icons can be switched on and off or set to display within or beyond range.
- Averaging can be switched between simple and weighted mean averaging.
- Values like exposure compensation, EV mode, cumulative flash mode, auto save and auto power off can be switched on and off.
Adjusted settings are saved to the meter’s memory chip. Consequently, if photographers wish to make further adjustments they must restore the values to the default settings. Pressing the memory clear button deletes all values stored in the meter. You can also selectively delete stored readings once you’re finished with them – or if they are no longer required.
The L-758DR comes with a built-in RT-32 Pocket Wizard- compatible radio triggering system that eliminates the need for synch cords, making flash photography fast and easy. To use the system, each electronic flash unit must be fitted with a suitable receiver or transceiver. Users can then control up to four channels via four dual-purpose buttons on the control panel. The selected channel is displayed on the meter’s LCD.
Pressing the measurement button triggers the selected flash and measures its output simultaneously. With additional Pocket Wizard triggering radios and receivers, studio photographers can activate both flash units and a camera with the Sekonic meter.
The meters imported into Australia use the Euro Standard (CE) frequency which is 433MHz.
As well as being a very capable light meter, the L-758DR’s sensor profiling function can provide real time-savings for photographers at the editing stage of their workflows. Once the response levels of the camera’s sensor are established and stored in the L-758DR, it is easier to obtain consistent, correctly-exposed shots because pre-exposure warning signals will alert you when you exceed the sensor’s dynamic range.
But it’s important to understand that ‘correct’ exposures are not always the ‘best’ exposures for all types of shots. Some subjects look better slightly over-exposed, others slightly under. The benefit of having a ‘correct’ exposure value is that you can decide where the ‘best’ exposure point lies, thanks to a clear understanding of how the subject brightness range fits into the dynamic range of your camera’s sensor.
Type: Digital exposure meter for ambient and flash light
Light receptor element: 2-Silicon photo diodes (incident and reflected)
Reflected metering distance: ~1m to infinity
Metering modes: Ambient ““ Aperture & shutter priority, EV metering; Flash (cumulative and non-cumulative) ““ with/without synchro cord, with built-in wireless flash triggering radio triggering system.
Measuring range (ISO 100): Incident light: EV-2 to EV 22.9, Reflected light: EV 1 to EV 24.4 with 1 ° spot viewfinder; Flash: Incident – f/0.5 to f/161.2 (approx. f/175); reflected – f/2.0 to f/161.2 (approx. f/175) with 1 ° spot viewfinder; repeat accuracy – +/- 0.1 EV or less
Radio triggering: Complex 16/24 bit digitally coded, range up to 30 m; 1 to 16 channels standard, 17 to 32 “Selective Quad Triggering”
Display range: ISO 3 to 8000 (in 1/3 steps)
Weather resistance: JIS standard water resistance class 4, splash-proof type
Memory: 9 readings on analog scale (f/stop and shutter speed) with memory recall and clear feature
Multiple flash: Unlimited flash readings (only one digit is displayed when the cumulative number is 10 or more); up to 9 readings can be averaged
Compensation: Exposure – +/- 9.9 EV (in 1/10 stop); Calibration – +/- 1.0 EV (in 1/10 stop)
Power source: One CR123A battery (3V Lithium dry cell); rated for 60 hours
Dimensions(wxhxd): 90 x 170 x 48 mm
Weight: 268 grams (with battery)
Supplied accessories: Soft case, strap, lens cap, synchro terminal cap, CR123A Lithium battery, Custom Settings Chart (sticker), Multi-Function Chart (sticker), USB cable, Data Transfer Software
Distributor: Camera House