Dr. Strangemeter - Or How I learned To Love The Diffusion Disc

Thanks to a conversation overheard this morning, I have a blog topic.

Light meters.

If you are carrying a digital camera, you are carrying a light meter. Depending upon the make and model of camera, it might share the knowledge it has of the world with you or not - but it most certainly will impose its will upon your images - generally for the better.

Set your camera to Auto, Aperture Priority, Shutter Speed Priority, or Program, and you will be helped by the meter. Set the camera to Manual and you are on your own, though the meter may try to prompt you to make a sensible decision in some way. Some have little bar graphs - some have little warning lights that flash. The Flapoflex D has a plastic bar that comes out and pokes you in the eye if you are more than 5 stops out...

If you've got an older film camera - or a camera that is meant to be used by people who know what they are doing - it probably won't have a meter. You are expected to buy a separate meter and take exposure measurements yourself - or not, if you prefer to be an iconic art treasure of the 21st century.

Let's start off right now by saying that the meter built into your DSLR, mirror-less, or compact camera is smarter than your brother-in-law. Those of you who point out that a jug of milk is smarter than the brother-in-law have my sympathy. The meter may be capable of seeing multiple things about the scene in front of it - looking at dark and light with a clinical precision. It has the benefit of programming that has seen many such scenes before and can work out the best compromise for the shot. This works under a wide range of illumination. It is still possible to present the meter with a scene that is too dark, too bright, too contrasty, too flat, or too weirdly-lit and if you continue to press the shutter button after the " Danger Will Robinson! " announcement the meter will just let you go ahead anyway.

The meters will work effectively with their sister circuits built into dedicated flash guns - they will decide between themselves how much of the exposure can be safely taken from the ambient light and how much must be paid for in electricity. The wise photographer might ask them to bias the thing one way or the other, but after asking should let them get on with it and be grateful for the help. Anything is better than those little aluminium dials that sat on the back of older flash guns.

Do you need a separate meter anyway? Well, apart from the film people with big cameras, the other use of the hand-held meter is to pre-determine the range of exposure you might want, to look at the evenness of illumination on a flat art work, or to minutely analyse a scene in case there are any anomalies in it.

What you do with the anomalies after you find them is your affair, but I tend to expose for the highlights, shadows, and mid-tones and then skew the D-max to the over-temperature zone VII before dropping the gradient mask into the toe of the K-curve. You'll see the effect in the image of the Mississippi traffic patrolman at the top of the page.

Uncle Dick

Travel Light with Gossen and Sekonic

You might think it superfluous these days to carry a hand-held light meter - what with all digital cameras containing their own light metering capability and never being wrong and always giving you perfect exposure every time. Oh, look, there's another flying unicorn...


Where was I? Ah, yes - the Gossen meter and the Sekonic meters. Got 'em both in stock and it looks like some people still use them...to check flash exposures before they light the fuses...to get the exposure right before the model stalks in and glares at them...to get accurate exposure even when the matrix-all-over -whatever-you-want-Boss meter in the camera insists on something that looks horrible.

They buy the small light models and take them in their shirt pockets when they go bush with the panoramic or large format cameras. They pop them out at weddings before the bride arrives to see if the church is dim enough...and there are churches here in Perth that do dim on an industrial basis. You can generally tell from their contact sheets or presentation sites that the exposures are dead on...without having to be shot 15 different times with an air of increasing desperation.

Of course, if you want to sit up until 2:00 AM recovering your exposure on the computer, please do. I'm going to use an exposure meter.

New Sekonic L-308DC Digi Cine Mate

Sekonic have released a new exposure meter designed for both the cinematography and still image market.  This is not a new concept but the L-308DC is the first compact entry level metering system to incorporate both fields of imaging making.

A full brochure for the L-308DC is available for download here

Sekonic DigiCineMate L-308DC
The versatility of today's cameras is expanding at an amazing rate. Digital SLR cameras are used to record moving images and digital video cameras are used to capture still frames for printing. Whether you are a DSLR videographer, cinematographer, still photographer or involved in any facet of image capture, the Sekonic L-308DC is the perfect meter for you.

Three Ways to Meter


The compact, Sekonic L-308DC is the first meter that can be customized to display only specific functions needed for the task at hand for fast, easy operation.
    •    DSLR videographers can make exposure readings and control light using shutter speeds and frame rates and get aperture settings with one-tenth stop accuracy. The display can be customized match your camera in full, 1/2 or 1/3 step readings. Brightness display in Lux and Foot Candles make it perfect for lighting-design work.
    •    Cinematographers can make exposure readings and control light using the most useful frame rates and shutter angles and get aperture settings with one-tenth stop accuracy. Exposure display can be customized to match your camera and Lux and Foot Candle readout enables quick set up of lights.
    •    Traditional still-image photographers will enjoy shutter-priority display of a full range of ambient and flash functions including Cord and Cordless flash measurement as well as EV. All with one-tenth stop accuracy and display that can be customized to your camera.

Three Ways to Measure Light

    •    The L-308DC's Lumisphere tells you about the light you are controlling. It is designed to integrate all of the illumination that falls on it, and the subject, including the key light, line light, hair light, eye lights, etc. Besides taking nearly foolproof exposure readings, its incident light reading enables you to set up and light a scene before the principal talent arrives. You can also “walk the set” to measure the evenness of the illumination.
    •    Snap on the accessory Lumidisc to measure for lighting green screens, adjusting ratios and taking lux and foot-candle measurements.
    •    Slide the Lumisphere to the right to measure light reflected from the subject or the brightness of light sources or window light.