Handheld light meter

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A classic handheld exposure meter with a cadmium sulfide measuring cell, two measuring areas and a light dome (front) for indirect measurements

A hand-held exposure meter is an external exposure meter that is available as a separate accessory and is mainly used in studio technology or for professional work. The integrated light meter is often not sufficient here, since several artificial light sources are used or a higher precision of the exposure is required than the internal light meter of a camera can provide.

When using more than one flash unit , the camera's built-in exposure meter cannot correctly calculate the exact amount of light, as the light sources only add up when the flash is triggered, which leads to overexposure. In these situations, the exact amount of light can only be determined with an external light meter. The parameters obtained from this can then be set on the camera in such a way that correct exposure of the film material is guaranteed.

The light measurement , which is mainly used by professionals , requires an appropriately equipped hand-held exposure meter.

Functions

Higher quality light meters differentiate between different functional groups such as photography and photometry ; They can then be used not only to carry out a contrast measurement, flash measurement, multiple flash measurement, etc., but also, for example, the illuminance or color temperature .

External hand-held exposure meters can usually measure light and objects (more precisely: luminance measurement ) for both continuous and flash light or convert the measured values into any units.

variants

Small exposure meters can sometimes be pushed into the accessory shoe of cameras instead of the viewfinder or a flash. Individual hand-held exposure meters can be switched between simple, so-called integral measurement with a wide measurement angle, and spot measurement with a narrow and very narrow measurement angle. Many system light meters have different diffusers or sun visors with which the measurement and angle of incidence can be varied.

precursor

While today's devices usually have a digital function and LED display, older models have a no less precise needle. The respective aperture-time film values ​​can be determined by means of a tracking system and coupled reading disc or by means of a reading scale for the EV / LW value and a separate calculating disc. The actual exposure measurement is done by a photo resistor (CdS etc.) or a selenium cell based on the principle of the solar cell.

In the early days of photography, the exposure value was necessarily estimated or calculated using tables from the year and time, weather and subject. For the simplified flash calculation one used and continues to use the object distance and the flash or lamp value or use a fixed standard value. Since the film material used or the darkroom work may undo small mistakes, this is quite practical for many recordings. Even today, taking pictures with very simple and cheap cameras works according to this principle when the weather is nice. Even with better cameras, one tries to empirically heuristically determine the best value in certain situations by shooting so-called rows with different exposure values.

As an alternative to the electromechanical exposure meter, photo-optical devices were also found earlier, which allowed a more precise estimate of the correct value by comparing the motif with the device's internal gray-scale film templates when looking through them.

Differentiation areas

A distinction is made between the following special handheld exposure meters:

Vendors and Products

  • Gossen : Mastersix , Polysix electronic u. a .;
  • Minolta : Autometer VF , Flashmeter VI and Colormeter III F as well as Spotmeter F ;
  • Sekonic : L-398A Studio Deluxe III , L-758D DigitalMaster , C-500 ProDigi Color , L-208 TwinMate u. a .;

See also

Web links