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amilne
24-Nov-2007, 08:47
I posted this over on Pnet... and, of course, received dozens of wildly different answers. I thought I'd post it here in the hopes that someone actually knows what they're doing.

<This is a silly question, but it's been bugging me.

I almost always use reflected in camera metering, or a reflective meter. Recently I got a camera without a meter, and so have been using this great little tool.

http://www.bhphotovideo.com/c/product/257033-REG/Gossen_GO4006_Digisix_Ultra_Compact_Lightmeter.html

Since it isn't quite like a normal ambient meter, that is, the dome is on the top of the device instead of fastened to the front, are there any different techniques I should use because of this fact? I have been pointing it straight up, with the LED display facing the lens (not the dome). It has been working out so far.

If I remember correctly the correct procedure for metering a subject with a standard ambient meter was to point the dome back at the camera. Does that still apply with this meter?

I'm using natural light.

Thanks>

Bjorn Nilsson
24-Nov-2007, 09:07
In short, yes, you should point the dome back at the camera. This type of metering measures the light that falls on the subject photographed. There are lots of threads already written on the subject and quite a lot of articles too. There should be one article from Kodak which I cannot find, but if you want to learn metering, that is really the one to read.
Also, ambient metering is often easier to manage, as you don't have to find a "normal gray" to meter from. Just meter the light which falls on the subject and dial it in on your camera. As with any non TTL metering you do have to deal with filter factors and close-up factors, but that goes with almost any photography which is filmbased from medium format and up.

//Bj&#246;rn

venchka
24-Nov-2007, 09:26
The Digisix is really no different than my Luna-Pro sitting next to my keyboard. For incident readings, slide the white dome over the sensor, place the meter at the subject or in a similar orientation as the subject, and point the white dome at the camera lens. You can also use the meter for reflected readings. If I remember correctly, doesn't the meter have an accessory shoe for camera mounting?

Maretzo
25-Nov-2007, 02:14
Here is the Kodak article: http://www.kodak.com/cluster/global/en/consumer/products/techInfo/af9/index.shtml

Rob Champagne
25-Nov-2007, 03:03
I use a spot meter and have never used this type meter. However I have read up on them and often see it written that you should point the meter at the camera lens.
Why? This just doesn't make sense to me. If I were in a studio and had a black wall behind the camera but had a light source at 45deg right and 45deg up from my subject, then what I would be metering is not the amount of light falling on the subject, but some point between what is behind the camera and where the main light source is coming from. It seems more logical to point the meter directly at the main light source therefore getting accurate readings of how much light is actually falling on the subject.
Please explain....

Remigius
25-Nov-2007, 07:18
I use a spot meter and have never used this type meter. However I have read up on them and often see it written that you should point the meter at the camera lens.
Why? This just doesn't make sense to me. If I were in a studio and had a black wall behind the camera but had a light source at 45deg right and 45deg up from my subject, then what I would be metering is not the amount of light falling on the subject, but some point between what is behind the camera and where the main light source is coming from. It seems more logical to point the meter directly at the main light source therefore getting accurate readings of how much light is actually falling on the subject.
Please explain....
If the light doesn't come from the same direction you're shooting from, it is spread over a larger surface of the final image and therefore attenuated (an easy assumption would be to shoot a surface perpendicular to the optical axis and hence parralel to your film). The dome accounts for this effect. Of course, there are situations in which such a simple model is not accurate, but you're still free to use other metering methods.

Daniel Geiger
25-Nov-2007, 07:29
I use a spot meter and have never used this type meter. However I have read up on them and often see it written that you should point the meter at the camera lens.
Why? This just doesn't make sense to me. If I were in a studio and had a black wall behind the camera but had a light source at 45deg right and 45deg up from my subject, then what I would be metering is not the amount of light falling on the subject, but some point between what is behind the camera and where the main light source is coming from. It seems more logical to point the meter directly at the main light source therefore getting accurate readings of how much light is actually falling on the subject.
Please explain....

In the studio, you point the meter back at the camera <i>from the position of the subject/object</i>, so no problems with angles of lights. That's the same idea is with grey card held by the model, not placed 5 cm in front of the lens.
Outdoors, however, the sun is at an infinite distance, so you *assume* that the lighting close to the camera is the same as right at the subject. If that assumption does not hold, then you have to either guestimate, or go for reflected reading.
Whenever I can, I use incident readings. Much more consistent and also easier. Works beautifully even with flashed close-ups/macro plus reflectors.

RDKirk
25-Nov-2007, 11:59
then what I would be metering is not the amount of light falling on the subject, but some point between what is behind the camera and where the main light source is coming from.

Yep. That's because the light reflected to the camera to form the image is the light between what is behind the camera and where the main light source is coming from.

Let's say not only did you have a main light but also a fill light at the camera position. If you pointed the meter at the main light, you get a reading for the main light. But part of the subject as seen by the camera is being illuminated by both the mainlight and overlapped by the fill light. Your reading must consider both sources.

Gordon Moat
25-Nov-2007, 12:28
http://www.sekonic.com/classroom/classroom_2.asp

Sekonic have a nice and simple display of incident and reflected metering. There are a couple links on the right mid area that include a little more.

Probably more B/W photographers on this forum, and most of them doing spot metering. This is basically a very narrow range reflected reading, though if you learn how to do it properly it can be quite helpful. Do spot metering badly, and it is a great way to ruin tons of film. Of course, I will probably catch lots of flack for stating that.

Mostly I shoot transparency films, so I do incident readings. I measure the light falling upon a subject, and set my aperture and shutter accordingly. When I do shoot B/W film, I treat that like transparency film too, and use the same metering.

Really it comes down to finding consistent methods that allow you to repeat results. To some that will be spot metering, careful measuring, zone system or some variation. Others will find taking another camera along, and transferring the in-camera meter reading to their view camera works fine. Then there are a few people like me who have tested their meters against bracketed film rolls, and just use incident readings. You don't know which will work best until you try, so do some experimenting and find what works for you. Best of luck and light to you.

Ciao!

Gordon Moat Photography (http://www.gordonmoat.com)

chris_4622
25-Nov-2007, 12:51
I've been considering getting a Digisix for hiking. It weighs 1.5 oz. compared to my spot meter weight of 10 1/2 oz.

Tom Perkins
26-Nov-2007, 06:26
It may be necessary to take a couple of extra readings when using the incident meter outdoors in a high contrast situation. This is explained better than I can do in Phil Davis's Beyond the Zone System, but as I understand it, the incident meter reads the light falling on the meter dome, so in a high contrast situtation, if it is in direct sunlight, it will give a high reading, and in the shadows it will give a low reading, which can help you decide whether to increase exposure, reduce development, or take some other steps to manage the excessive contrast.