Light meter (and metering) questions

[larry480]

Hi, I'm just studying LF photography at the moment -- haven't bought any equipment yet. So please excuse what might be a stupid question about light meters. First, do you meter the light using a meter on the focusing ground glass? (I expect I'll be doing mostly landscapes and architectural shots where I won't be able to get close to the subject). Also, I'm trying to learn and understand the zone system. So what do i need: incidental? reflective? spot?

Thanks a lot for ay help you can provide?

[aduncanson]

Some folks use incident meters, others reflected. To say that one is superior or more natural than the other would be to invite a flame war that would not shed much light.

That said, I own both types but reach for my Zone VI modified Pentax 1 degree spot meter first. Most basic Zone System books, Minor White The Zone System Manual or Ansel Adams The Negative for example, discuss principally, if not exclusively, the use of reflected light meters. Adherents of incident light meters frequently refer to Phil Davis' Beyond the Zone System.

With a reflected meter, one meters the scene directly. I would think that there is too much light lost passing through the lens and the ground glass, and anyway the meter is calibrated to read the scene directly.

[cyrus]

With an incident meter you don't have to be close to the subject as long as you're in the same lighting.

You don't measure the light off the ground glass - you measure off the scene (I've only run into one instance of scientific photography where the lightmeter reading was taken off the groundglass using a special accessory.)

What lightmeter you'd need for the Zone system depends on how much of the Zone system you actually implement. If you stick to the old tried-and-true "Expose for shadows and develop for highlights" thing then you can do so quite nicely with an incident meter and then stopping down two stops for the shadows - and lots 'n lots of photogs stick to that. Rarely would a reflected lightmeter - when used properly - give you much of a different result than an incident one.

IF you decide to use the Zone system IN FULL, you'd definitely need a spot lightmeter. However then you'd also have to engage in lots of testing can calibrating of your other equipment and film/paper.

[cowanw]

Actually there is a Horseman exposure meter 45 which you will find used. This does read the average reflected light of a scene from the ground glass. Not everybodies cup of tea but it helps me particularily with bellows extension.

[cyrus]

Actually there is a Horseman exposure meter 45 which you will find used. This does read the average reflected light of a scene from the ground glass. Not everybodies cup of tea but it helps me particularily with bellows extension.

Yeah I think that was what I saw being used. It was in a lab though, they were doing some extreme close-ups with a view camera.

[aduncanson]

Actually there is a Horseman exposure meter 45 which you will find used. This does read the average reflected light of a scene from the ground glass. Not everybodies cup of tea but it helps me particularily with bellows extension.

Not "from the ground glass", but from in front of it. (http://www.cameraeccentric.com/html/info/horseman_1.html)

Sinar has offered a number of products (http://www.johndesq.com/pinhole/booster.htm) that work similarly.

[Leigh]

I use a Sekonic L-558 light meter. It's two meters in one, an incident meter and a 1° spot meter with separate optical systems, sharing a common display and set of controls. This is an excellent meter. I would strongly recommend you consider it.

I almost always use the incident function for determining the actual exposure.

If I'm shooting a high-contrast subject, I'll use the spot meter to determine the subject brightness range, and decide how I want to handle shadows and highlights based on that and knowledge of the film's behavior.

Regarding in-camera metering...
There is an exposure probe system available for Sinar cameras that spot-meters the scene in the camera immediately in front of the ground glass, on the lens side, not looking at the ground glass image. Like the Horseman system mentioned above, this has the advantage of automatically compensating for bellows extension.

- Leigh