The pocket-sized Sekonic L-308S-U Flashmate is the smallest and lightest digital light meter in the Sekonic line-up. It is designed to read ambient or flash exposures in either reflected or incident modes, and it displays accurate exposure readings in full, half, or third-stop increments to mirror the exposure settings of today's DSLR and film cameras.

The L-308S-U delivers accurate exposure readings in full-, half-, or third-stop increments to mirror the exposure displays of most popular cameras. When set to full-stop mode, exposures are displayed in tenth-stop increments with a repeat accuracy of +/- 0.1 EV.

The LCD screen is designed to emulate the look and feel of its bigger brother, the Sekonic L-358 flash meter. Exposure data and related information are displayed using large type and easy-to-read icons, perfectly legible in even low-level lighting conditions.


Incident or reflected light measurement

  • Reflected light readings are captured at a receiving angle of about 40 degrees for subject readings made at the camera. Slide the L-308S-U's built-in Lumisphere over the silicon photo diode for incident light exposure readings of three-dimensional subjects. Snap on the included Lumidisc over the sensor for metering flat artwork or measuring contrast and/or exposure ratios within a scene.

Ambient / Flash measurement

  • Incident or reflected ambient light readings can be made with the L-308S-U over a wide range of lighting conditions at shutter speeds from 60 seconds to 1/8000th of a second and apertures from f/stops of f/1.4 to f/90.9. Flash at speeds from 1 to 1/500th of a second can be measured cordless or wired using a separate accessory PC cord. Flash and ambient readings are automatically calculated to display the proper exposure for the combination.

Accurate measurements

  •  Exposures accurate down to a tenth-of-a-stop for both ambient and electronic flash light readings are available in full-stop mode. The L-308S-U can also display shutter speeds and apertures in half or third-stop increments to mirror the exposure settings on your camera with a repeat accuracy of +/- 0.1 EV. For cinema applications frame rates can be set from 8 to 128 frames per second. ISO sensitivity can be set from 3 to 8000 in third-stop increments.

Compact size and lightweight

  • The L-308S-U is the smallest digital flash meter for reflective and incident light readings in ambient or electronic flash lighting conditions. It is compact and light enough to fit into a shirt pocket, yet versatile enough to meet virtually every photographic demand. The L-308S-U is powered by a single AA battery and weighs only 3.4 ounces (95g). Its measurements are a compact 2.5"W x 4.3"H x 0.9"D (63mmW x 110mmH x 22mmD).


  • The Sekonic L-308S-U FlashMate comes with a Lumidisc (with pouch), soft case, strap, synchro terminal cap and an AA battery. It has a full, 1-year warranty, extendable at no charge to 3 years total (in the USA only) after registration, and is backed by our outstanding customer support team.

Technical Specifications

  • Type: Digital exposure meter for ambient and flash light
  • Receptor Head: Sliding Lumisphere with Lumidisc Adapter
  • Light Receiving Method: Incident light and reflected light
  • Receptor Incident Light: Built-In Lumisphere, Attachable Lumidisc (included)
  • Receptor Reflected Light: Lens with 40° Receiving Angle
  • Light Receptor Element:  Silicone photo diode

Measuring Range and Modes

  • Measuring Modes Ambient Light:
    •  EV metering
    • Shutter priority metering
  • Measuring Modes Flash:
    • Without synchro cord
    • With synchro cord
  • Measuring Range (ISO 100) Ambient Light:
    • Incident light EV 0 to EV 19.9
    • Reflected light EV 0 to EV 19.9 (with 40° angle)
  • Measuring Range (ISO 100) Flash:
    • Incident light f/1.4 to f/90.9 (approx. f/124)
    • Reflected light f/1.4 to f/90.9 (approx. f/124) with 40° Lumigrid
  • Repeatability Repeat Accuracy:  (+/-) 0.1 EV or less
  • Calibration Constant Incident:  Lumisphere C = 340, Lumidisc C = 250
  • Calibration Constant Reflected: K = 12.5

Display Range and Modes

  • Display Range Film Speed: ISO 3 to 8000 (in 1/3 steps)
  • Display Range Shutter Speeds Ambient:    60 sec to 1/8000 sec. (in 1, 1/2, 1/3 steps)
  • Display Range Shutter Speeds Flash:    1 sec to 1/500 sec. (in 1/ 1/2, 1/3 steps) plus 1/75, 1/80, 1/90, 1/100 sec.
  • Display Range Aperture:    f/0.5 to f/90.9 (in 1, 1/2, 1/3 steps)
  • Display Range EV:    EV -5.0 to EV 26.0 (in 1/10 steps)
  • Display Cine Speeds fps:    8, 12, 16, 18, 24, 25, 30, 32, 64, 128 (shutter angle: 180°)


  • Exposure Out Of Range:    Eu (underexposure) or Eo (overexposure)
  • Auto Power Off:    Yes, About 4 minutes after last usage
  • Battery Power Indicator Display:    Icon with 3 status
  • Battery(Power):    (1) Type AA 1.5V Battery alkaline, manganese or lithium
  • Operating Temperature Range:    32° to 104° F / 0° to 40° C
  • Storage Temperature Range:    -4° to 140° F / -20° to 60° C

Dimension and Weight

  • Product Dimensions:    4.30x2.50x0.90 in./10.90x6.40x2.30 cm
  • Product Weight:    0.20lbs./0.10kg.
  • Item Includes
  •  L-308S Case, Strap, Syncro Terminal Cap and Lumidisc w/ case