Incident or reflective....old school light meter....

TooManyShots · Oct 17, 2012

I have a question about using an old school light meter, Gossen Luna Pro with the battery adapter. I shot my first roll of medium format film last week and using my Canon 30d to meter the scene. It works and the shots were a bit overexposed. With the Gossen Luna Pro light meter, I can meter the scene with ambient light or reflective. Let say I want to take a light reading of some tree during the fall foliage and there is a body of water (lake) in between me and the trees. The sun is at my back, 8 o clock. Do I meter this scene with the incident mode? Or do I meter off the reflective light coming from the trees? Would the reflective mode be accurate even when I am no where near my subjects?

Poisson Du Jour · Oct 17, 2012

Spot metering a mid-tone (partly shaded) area of the water, the fall foliage and other parts of the tree and grass/vegetation then averaging would be better than incident. Your 30d would be metering as a reflective meter by default, and likely in evaluative metering mode (thus, the algorithm of exposure follows the procedure of the Zone System). You could try incident reading from several angles, writing down each reading from each part of the scene, then averaging them all at the end. The problem with incident is that it assumes all parts of the scene are equal in luminance, when they are not, hence the purpose of a spot meter to measure each luminance independently. I am not, at all, a fan or exponent of metering scenes with digital cameras and extrapolating the result to film because it misses valuable learning in understanding how to meter critical parts of the scene to arrive at a correct exposure (although what constitutes "correct" is up to the photographer himself).

MattKing · Oct 17, 2012

I'm a big fan of using an incident meter.

If you are able to place yourself in a position that "sees" the same light as your subject, the reading you take will, IMHO, will be the most likely to assist you.

If you take a reflected light meter reading, you will always have to also analyze the acceptance angle of the meter and the reflectivity of the subject before you can reliably use that reading.

In the situation you describe, in order to take a reading off the trees, and just off the trees, you will either need to walk across the water or use a spot meter accessory to limit the angle of view of the meter. Alternatively, you can meter the entire scene and then, using judgement and your experience, estimate how much the reflectivity of the scene differs from the standard 12-18%, and adjust accordingly.

ic-racer · Oct 17, 2012

I'd call an extinction meter "old school."

cliveh · Oct 17, 2012

TooManyShots said:
I have a question about using an old school light meter, Gossen Luna Pro with the battery adapter. I shot my first roll of medium format film last week and using my Canon 30d to meter the scene. It works and the shots were a bit overexposed. With the Gossen Luna Pro light meter, I can meter the scene with ambient light or reflective. Let say I want to take a light reading of some tree during the fall foliage and there is a body of water (lake) in between me and the trees. The sun is at my back, 8 o clock. Do I meter this scene with the incident mode? Or do I meter off the reflective light coming from the trees? Would the reflective mode be accurate even when I am no where near my subjects?

In order to answer that question we need to know what type of film you are using.

TooManyShots · Oct 17, 2012

Thanks. I don't have the spot meter accessory for my Luna Pro. However, I think this should work by using reflecting metering and metering off the sky and the trees and the body of water in front of me, I can average the value. This should give me somewhat of an accurate reading. No, I don't want to carry my 30D with me while shooting with my medium format body. Obviously, incident reading may not be accurate because the area I am standing is generally under shades.

TooManyShots · Oct 17, 2012

cliveh said:
In order to answer that question we need to know what type of film you are using.

I am planning to do some shooting around 7am tomorrow. To capture some fall foliage scene. Fuji Reala 100.

MattKing · Oct 17, 2012

If you are using reflected light metering, be careful if you meter off of the sky, because it is emitting light, not reflecting it.

And be careful metering off of water, as smooth water reflects images, which can confuse the reading.

An averaged reading is only accurate if the reflectivity of the subject and the light falling on it averages out.

cliveh · Oct 17, 2012

Incident mode.

TooManyShots · Oct 17, 2012

MattKing said:
If you are using reflected light metering, be careful if you meter off of the sky, because it is emitting light, not reflecting it.

And be careful metering off of water, as smooth water reflects images, which can confuse the reading.

An averaged reading is only accurate if the reflectivity of the subject and the light falling on it averages out.

Thanks. What if I meter off the sky in the reflective mode and then the trees to see if there are a huge difference in the exposure values? I would assume the sky would have a higher value. If the difference isn't so great, I would assume averaging both values should give an accurate exposure reading.

Poisson Du Jour · Oct 17, 2012

Don't meter from the sky; just meter from those elements in the picture which need to be correctly exposed, and let the sky take care of itself as a "background" value. The only time I give any analysis to the sky is in contrasty sunsets, averaging a slightly third-left section of sunset with the foreground.

Are you using transparency, negative/colour or B&W film? If you are using transparency, exposure will be more critical than the quite relaxed allowance of negatives.

TooManyShots · Oct 17, 2012

Poisson Du Jour said:
Don't meter from the sky; just meter from those elements in the picture which need to be correctly exposed, and let the sky take care of itself as a "background" value. The only time I give any analysis to the sky is in contrasty sunsets, averaging a slightly third-left section of sunset with the foreground.

Are you using transparency, negative/colour or B&W film? If you are using transparency, exposure will be more critical than the quite relaxed allowance of negatives.

OK. I will bring my Canon 30D with me tomorrow just to test some reading against my Luna Pro. Even a reflective reading against my wall panel in my room has a 1 stop difference comparing to the incident reading. I am not sure what the reflective meter would be metering if my subject is some distance away. I am shooting with color negative, Fuji Reala 100.

Alan Klein · Oct 17, 2012

cliveh said:
In order to answer that question we need to know what type of film you are using.

I think you're the only person who picked up he's shooting digital on a film forum.

TooManyShots · Oct 17, 2012

Alan Klein said:
I think you're the only person who picked up he's shooting digital on a film forum.

I shoot both... And doing paid gigs with digital of course.

summicron1 · Oct 17, 2012

all meters are advisory only. if ur looking for a way to meter that gives you one shot at a good exposure, ur dreaming. Meter like crazy, then bracket 1/3 stops for a stop in either direction. When you get the film back you can see which worked best.

Poisson Du Jour · Oct 18, 2012

summicron1 said:
all meters are advisory only. if ur looking for a way to meter that gives you one shot at a good exposure, ur dreaming. Meter like crazy, then bracket 1/3 stops for a stop in either direction. When you get the film back you can see which worked best.

:confused:
I don't see how 0.3 step brackets will have any effect on negative film (especially Reala) given its very generous latitude. Commonly neg film is bracketed to +/ 2 stops to bring up the event horizon, then work incrementally forward and back from there. This is not the same as with transparency film where 0.3 steps to 0.5 (or 0.6) steps are most commonly used except for deliberate low or high key shooting.

Poisson Du Jour · Oct 18, 2012

TooManyShots said:
OK. I will bring my Canon 30D with me tomorrow just to test some reading against my Luna Pro. Even a reflective reading against my wall panel in my room has a 1 stop difference comparing to the incident reading. I am not sure what the reflective meter would be metering if my subject is some distance away. I am shooting with color negative, Fuji Reala 100.

Incident is light falling on the subject; reflective is light coming off the subject viewed by the meter/camera. This is chiefly why incident is reliable for nailing some (but not a lot) of exposures, with the only other refinement being multi-spot metering.

I would view your 30d metering as potentially very misleading with a 1 stop difference comparison and urge you to concentrate on using incident metering with aim-back to camera from subject. It's not perfect but will eliminate the margin of error caused by an evaluative metering system that is averaging the luminance of several small areas of reflected subject light.

markbarendt · Oct 18, 2012

TooManyShots said:
I shot my first roll of medium format film last week and using my Canon 30d to meter the scene. It works and the shots were a bit overexposed.

Having metered with anything, at the right EI, I find it a bit tough to believe that your Reala was seriously overexposed.

Negative films can typically handle 2-4 stops of extra exposure without losing detail.

My guess is that the negatives are fine and the lab you used didn't try very hard.

TooManyShots said:
Obviously, incident reading may not be accurate because the area I am standing is generally under shades.

Actually it is still very accurate, you simply need to understand that the meter is just giving you a reference point rather the camera setting.

All you need to do is decide how much different the two are. You simply apply zone system principles as you would with spot metering.

newcan1 · Oct 18, 2012

I've taken shots just like this before. With my old Weston Master, pointing toward the trees and adding a stop (to compensate for the sky and water) usually gives the correct exposure.

Chuck_P · Oct 18, 2012

TooManyShots said:
Do I meter this scene with the incident mode? Or do I meter off the reflective light coming from the trees? Would the reflective mode be accurate even when I am no where near my subjects?

The skinny of it is that it does not matter which one you use, a well executed photograph can be had from both ways, regardless of the film used. It does matter though, how you might use either method. I prefer reflective because it tells you what the actual reflective values are that will be reaching the film, but you have to be keenly aware of how much of either the dark areas or the light areas are influencing the meter's reading.

baachitraka · Oct 18, 2012

Incident meter(Negative film) Bright Light: Close down 'one stop' if metering is based on 'shadow' and open up 'one stop' if metering is based on 'hightlight', provided that scene has both shadows and highlights.

Diffused Light: Just incident meter the scene. If not, adjust after testing.

Incident meter(Slide film): Just incident meter the scene since its range is 5 stops.

TooManyShots · Oct 18, 2012

Thanks for all of your imputs but I think I have my answer this morning. I didn't take any shots but did a bunch of readings cross referencing with my Canon 30D. Is reflective. I can't meter the incident light when the subject isn't even remotely near what I am standing. Needless to say, using the incident reading I would get overexposed shots. With metering with reflective lighting, I first meter off the sky since the reading should be constant. I then point my light meter to the scene in front of me. If I am getting no less than 1 stop difference, which means I am meaning off too much of the sky. Then, I point my light meter a bit towards the ground/water, I would get a bit more than 1 stop of exposure difference. That's the correct reading and I verified the reading with my DSLR and the historgram too.

benjiboy · Oct 18, 2012

The light meters in digital cameras are designed for that cameras individual sensor not film , so I.S.O 100 on a digital camera isn't the same as 100 I.S.O on a hand held separate light meter and film which is why the readings don't agree, if you want to use a reflected/incidental hand held meter use film.

Diapositivo · Oct 18, 2012

TooManyShots said:
With the Gossen Luna Pro light meter, I can meter the scene with ambient light or reflective. Let say I want to take a light reading of some tree during the fall foliage and there is a body of water (lake) in between me and the trees. The sun is at my back, 8 o clock. Do I meter this scene with the incident mode? Or do I meter off the reflective light coming from the trees? Would the reflective mode be accurate even when I am no where near my subjects?

First rule: incident light metering is executed by placing the light meter near the subject and pointing it toward the camera. That's VERY different from reflected light metering, which is performed by pointing the light meter toward the subject.

Second rule: if you cannot walk to the subject, because there is an obstacle in between or simply because the subject is far, you try to make a measure in the same light conditions of your subject.

In your case, provided you are in the same light conditions as the trees, you only need to turn yourself, and point your incident light meter toward the light falling on the subject, with the same angle it would have if pointed from the subject toward your camera. In your situation, you would point the incident light meter while leaving the sun at 2 o'clock.

This reading will be very reliable unless the light falling on the subject is different from the light falling on your light meter.

As an example, imagine the pond you mention reflects some light on the trees, but does not reflect any light on your light meter because you are on "this" side of the pond in relation to the sun.

This is where you begin applying reasoning. If the pond reflects some light on the trees, you can do two things:

- Close half stop or an entire stop if REALLY you can can evaluate the effect by eyesight and it is "dramatic";
- Just use your incident light reading "as is" because you are using a negative film which will easily digest any degree of overexposure.
- If some details in the shadows are important, or better said if the shadows of your scene are overall "weighting" for extension and importance, then you can even open 1 stop in relation of the incident light metering. That will let your film "dig into" the shadows opening them very well while, again, the colour negative material will stretch to the highlights retaining details without effort.

Fabrizio

baachitraka · Oct 18, 2012

TooManyShots said:
Needless to say, using the incident reading I would get overexposed shots.

Not only you get the shots overexposed(metering shadows only), but also possible to get them underexposed(metering highlights only).

The simplest solution for B+W negative is to meter at shadows and close down a stop.

Example, incident shadow reading say EV 8 then shoot at EV 9.

I presonally have no trouble with roll films. If you are shooting sheets you may need slightly more sophisticated technique which is very well explained in BTZS book.

Incident or reflective....old school light meter....

TooManyShots

Poisson Du Jour

MattKing

Moderator

ic-racer

cliveh

TooManyShots

TooManyShots

MattKing

Moderator

cliveh

TooManyShots

Poisson Du Jour

TooManyShots

Alan Klein

TooManyShots

summicron1

Poisson Du Jour

Poisson Du Jour

markbarendt

newcan1

Chuck_P

baachitraka

TooManyShots

benjiboy

Diapositivo

baachitraka

Incident or reflective....old school light meter....

Moderator

Moderator

Privacy & Transparency

Privacy & Transparency