OddJobber Loc: Portland, OR

Sorry, Gene, but this is all confusing to me. By adding one stop do you mean to increase or decrease the aperture opening?

drmike99 Loc: Fairfield Connecticut

Adding a stop means to increase the exposure by one full f stop, such as going from f/5.6 to f/4 or f/16 to f/11.

LWW Loc: Banana Republic of America

Matrix rocks.

I can hand meter as well as matrix metering can, but nowhere near as fast.

LWW Loc: Banana Republic of America

It’s really a Stone Age attempt at matrix metering where it uses a much larger center area than spot metering and ignores the rest.

blackest Loc: Ireland

It's worth taking a look at how color works in terms of tone
https://photography.tutsplus.com/tutorials/understanding-using-ansel-adams-zone-system--photo-5607

Have a look at zone V this is what your camera meter is aiming for when it calculates an exposure. The color patches on that row are all the same tone in terms of brightness. If you use a spot meter on any of the Tones on zone V all the other tones will fall in their correct zones and the picture looks right. Under the light that you have. Lets say your camera figures f5.6 1/200th iso200 is the correct exposure for the mid grey chip in tone V what happens if you over expose it by a stop. which you can do by changing f-stop, or shutter speed, or iso.

correct is f5.6 1/200th iso 200
f4 would double the size of the aperture and if you keep the same iso and shutter speed the exposure will be 1 stop over exposed
maybe we change shutter speed to 1/100th the exposure is twice as long and is 1 stop over exposed.
or change iso to 400 now the camera is twice as sensitive to light and is 1 stop over exposed.

if you want to under expose then changing aperture to f8 or shutter speed to 1/400th or iso to 100 would under expose 1 stop.

The result of over exposing 1 stop is to shift everything up a stop so everything that should be in zone V looks like it is in zone Vi every thing moves up a zone. under exposing shifts everything down a stop zone V now looks like zone IV.

Zone VII is the highest zone which has any color to it less than just white over exposing 1 stop just turned all of the zone VII colors white.

Spot metering just looks at the chip under the meter if that chip is in zone V everything is fine and dandy if its in a zone 1 stop higher then it will expose to put it in zone V and you get under exposed by 1 stop if it is 1 stop lower in tone the exposure gets increased by a stop.

Thats no good so why use it? well if you look at any scene its fairly easy to figure out where the brightest tones are so you aim it at the brightest area that you want detail not necessarily the brightest spot and the meter will try to set an exposure where that would be mid gray zone V.

Gene said to under expose 1 stop but thats still 1 stop over exposed if the tone should be in zone VII but he shoots raw and there is still a stop more of detail recorded and he can pull down that highlight back down to zone VII in post processing. You can't do that with a jpeg so you need to use 2 stops compensation.

Ok thats a tad tricky to do so what about the other metering modes, those color chips you will have to imagine they are all together without the white background. if your camera is just looking at the chips on average the overall level is zone V there are chips in zone VII that are 2 stops over but there are chips in zone III that are 2 stops under so they cancel each other out. This works fine if the scene over all averages to zone V

But lets say your photographing a model on a sandy beach there is more beach than model so over all the scene is brighter than zone V on average so your camera under exposes and your model is too dark.

Centre weighted basically says forget the beach lets get the model exposed correctly she is much closer to being zone V on average and the camera makes a better job of exposing her close to the right exposure, the sand is closer to being the right shade too.

Lets get back to bowling if the lights are steady then there is no increase or decrease in light on the scene. The actual lanes will tend to be quite brightly lit and as long as thats where you are pointing the camera the light doesn't change once you have your level you can stick with it, over at the bar there is usually less light so you will need to meter again to get the exposure right.

If its a disco with lights flashing on and off it's pot luck as to getting the exposure right. The light maybe quite different between the camera metering it getting the mirror up and exposing it.

Your camera meters using reflectance and the amount of light measured depends on the tone of the object that is being bounced off.
An incident light meter has a white plastic dome the amount of light it sees depends entirely on the quantity of light but you need to have that dome ideally at the subject and pointing towards where you will take the photo, if the light isn't changing you can stick with the same exposure.

sum up
Light meters aim to correctly expose for zone V if what you are metering from isn't zone V then you are going to under or over expose.
Spot metering takes some figuring out.
Matrix metering aims to average out the whole scene as zone V that may not be correct.
Centre weighted metering aims to get your main subject metered correctly at zone V and the rest can fall were it falls, you may lose details at the edges due to being too bright or too dark but your main subject should be ok.

Finally hope your bowling teams are not wearing day-glo colors as that will totally throw the exposure off.

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

By increasing one stop I mean adding more light. You can do this by increasing ISO, using a slower shutter speed, or opening the lens - adjusting any of the parameters by one stop.


Blackest covers it in detail, but put simply, the spot meter measures light and not subject matter. It doesn't know or care what you are shooting. It only cares about the reflectance (or luminosity, I forget which) of the "thing" it is pointed at - and it gives you a reading to make it appear middle gray.

If you point it at a white cat, and use the reading as is, the cat will be gray. If you point it at a black cat, the same thing will happen. In order to render the white cat as white, you need to increase exposure. In theory that also works for the black cat - you'd have to reduce exposure to make it darker than middle gray.

This requires some evaluative skills and experience with your camera to know how much to adjust the reading.

In theory you use a gray card, and put it in the scene where there are a black and white cat with all three getting the same light, and measure the card to get a proper reading for the entire scene, or you can read either the black cat or the white cat and adjust accordingly.

Now things can get interesting - you may have a black cat sitting under a bench, in deep shadow, and the white cat basking in the sunlight on top of the bench. What do you do then? My first take would be to meter the white cat, add as much exposure as I can without losing important details, and just do what I need to in order to get some details out of the black cat. The black cat may be muddy, noisy and lacking detail, but that can be somewhat fixed in post processing. The other approach is to take two or more shots - one or more to get the black cat exposed properly and the other to get a good exposure on the white cat. But that would require considerable work in Photoshop or other application to merge the two images into one.

Using a gray card, or even an incident meter, would not be able to resolve this lighting dilemma - You'd still need to make a choice.

Shooting to get the most exposure possible on the white, sunlit cat is one way to "expose to the right" - a term that is often misunderstood.

One last scenario - the black cat, alone, with nothing bright in the scene that is important. There is nothing wrong with recording the black cat as bright as possible - then adjusting the brightness in post processing. The result will be less noisy than if you were to use one stop less exposure. It would be tonally correct to do that, but from an image quality point of view, the higher exposure would look better after adjustment. Low contrast scenes can also be recorded with less noise by exposing brighter and adjusting in post later, as long as nothing important is "blown out" or completely lacking in detail.

None of this is easily done when you only have a jpeg to work with. These kinds of adjustments have the best outcomes when you start off with a raw file.

OddJobber Loc: Portland, OR

Thanks Gene and Blackest for the explanations.

I think my problem with ETTR is that I don't want to blow highlights, but I haven't considered the effect on noise, which I hate.

selmslie Loc: Fernandina Beach, FL, USA

No, Gene51 and those who agreed with him are exactly correct. If the light is constant you don't need to keep metering it.

The only thing that might mess you up is if the lights are fluorescent and your shutter speed it to high.

blackest Loc: Ireland

Jpeg is a bit like a slice of cake while raw is the whole cake There is detail able to be pulled from the highlights that jpeg doesn't use and detail in the low end as well, generally at base iso 1 stop over can be useable but this spare cake goes down as ISO rises. It is possible that the extreme highlights are too extreme. Thats why Gene spot meters the highlights and drops a stop. That still may mean the exposure is under exposed for the subject. The jpeg programming may just concentrate on getting the subject at the right level this tends to lead to blown out skies but the subject looks ok...

selmslie Loc: Fernandina Beach, FL, USA

I don't think the OP is into raw yet.

SteveR Loc: Michigan

I have found that taking a photo of the same subject using the three different modes of metering will give me drastically different exposures. As said previously, the best thing to do is to experiment with various aperture and shutter speeds, based upon metering results, until you are satisfied with the results. Hopefully, once you've found the happy medium, shirts, balls, lanes, etc., will all come out exposed nicely.

DJCard Loc: Northern Kentucky

I would practice using Matrix metering along with “easy exposure compensation” (Nikon bodies), to see if works for you. For example, set up camera in aperture priority and rear command dial for exposure compensation. This allows one to take a shot, check exposure on LCD screen, quickly adjust exposure compensation with rear command dial (if needed), and take another shot, all without having to use/hunt for exposure compensation button. I suspect other camera bodies have similar set up available.