5D MKIII - images typically require exposure compensation?

bobbyz wrote in post #16201158
You shoot MF Zeiss but camera not in Manual.

The logic is strong with you

I assure you, if you shoot in evaluative and take a picture of someone in front of a black wall and then turn around and take a picture of someone in front of a white wall, if you have your camera "set" on +2/3 EC, neither of the pictures is going to be well exposed.

Lowner wrote in post #16200865
I adjust exposure to suit the subject. Never noticed if I'm adjusting up or down, never mind whether its 2/3rd of a stop or not. I suspect it varies depending on the subject and contrast levels.

JakAHearts wrote in post #16202019
I assure you, if you shoot in evaluative and take a picture of someone in front of a black wall and then turn around and take a picture of someone in front of a white wall, if you have your camera "set" on +2/3 EC, neither of the pictures is going to be well exposed.

Exactly. EC requirement varies according to the light and the tones of both the subject and the background. My 5D mk III gets used with +ve EC sometimes, sure. But I also find myself using -ve EC quite often to avoid losing detail in some subjects. I have never even considered where the EC would be set for a "typical" shot, my exposures are set (either with EC or in M mode) according to the exposure I need for the shot, that may be +1 compared to the meters suggestion, it may be -1, or a whole range of other options.

Most camera meters tend to underexpose slightly, left to their own devices, it is a safety feature. If you blow out highlights, you ain't getting them back, but slight underexposure is usually easily correctable in PP. So, camera meters are set that way to reduce the chance of critical areas being blown out on a subject in the sun.

At the end of the day, the meter reading from the camera is just a suggestion and it is up to the photographer to decide on the actual exposure used. Cameras don't under / over expose images, photographers do.

sandpiper wrote in post #16202412
If you blow out highlights, you ain't getting them back, but slight underexposure is usually easily correctable in PP.

Actually, a RAW file does not have equal amount of data on both sides of the spectrum - there much more information on the highlights side than the shadows. Thats why it is better to overexpose a little than underexpose. Have you heard of "shooting to the right"? Look it up ...

light_pilgrim wrote in post #16200406
Folks,
I might be just my case...I think that from time to time I get images that are too dark and require exposure adjustment in post processing vs what I typically would expect. You do not observe anything like this with your MKIIIs?

I had the same issue with my 5D III, bugged me so much I sold the camera ...

Ive noticed this. The metering "problem" wasn't this pronounced on my orginal 5D. I just have to pay close attention to what I'm doing, as I should

pixel_junkie wrote in post #16202435
Actually, a RAW file does not have equal amount of data on both sides of the spectrum - there much more information on the highlights side than the shadows. Thats why it is better to overexpose a little than underexpose. Have you heard of "shooting to the right"? Look it up ...

Yes, I have heard of it and do not need to look it up thank you, I shoot to the right all the time. The idea is that you keep the histogram over to the right, but shooting so that important details are completely off the right hand side of the histogram and blown out (which is what I was talking about when I described the safety feature) is NOT better as you cannot recover them.

Are you seriously suggesting that Canon should set their cameras to deliberately overexpose all the time, so that the histogram bunches nicely over to the right in flat lighting, but whites will go way past the edge in bright sunshine and just become a featureless blob?

In low contrast lighting, where the histogram is all bunched in the middle, yes of course you can "overexpose" and still retain all the detail as the histogram is still inside the right hand edge. In bright sunlight, the increased DR will mean the histogram spreads out and may be clipping slightly at each end, overexpose in that situation and your whites are toast.

Using Evaluative, try shooting a white bird against a dark background, in sunlight, with ANY +ve EC on at all, and see how much feather detail you can pull out in PS. The camera meter will already be overexposing the bird, because of the dark background (even cameras that "underexpose" such as the 5D mk III). I have used negative EC on many occasions, whilst still shooting to the right and having my histogram right over to the right hand edge.

ETTR is a good technique, but you can't just blindly set +ve EC and leave it regardless of the subject and background. It is still up to the photographer to decide on the settings to use (whether +ve or -ve compared to the meter reading) even when shooting to the right.

Canon sets the meter to avoid blowing highlights in bright sun, as that is bad (you do agree on that?). That means that, when shooting in lower DR conditions, the meter will suggest lower exposure than the photographer may wish (particularly if they like to ETTR). However, the photographer doesn't have to accept the cameras choice any more than they need to use "all points AF" and let the camera focus where it wishes. The camera is a tool, the meter is just something that gives you a reading, which you then interpret and adjust as you see fit, the same as any other settings. The actual exposure is up to the photographer, unless they choose to let the camera make that decision for them. The built in "underexposure" is just a safety feature for those shooting in automatic and not thinking about what the correct exposure may be.

Canon's autoexposure algorithm is based on the average brightness of all zones measured in the scene. As such, EC should be based on whether the scene has a high DR (-EC), low DR (+EC) or average DR (0 EC). This average dynamic range seems to have increased by a stop, so where you would have dialed +1 on your 5D/5D2, you'll now need to dial +1.5 on your 5D3. Or where you would have dialed -1 on your 5D/5D2, you'll need to dial -0.5 on your 5D3. I think Canon did this because it was found that most scenes photographed are closer to 7 stops than the 6, to which the earlier 5Ds where callibrated. But I don't understand why this is a problem.

Edit: Here's a post I wrote a few days ago that has more detail:

https://photography-on-the.net …p?p=16193948&po​stcount=20

I think is it very smart of canon to have the camera default to underexpose a tad. I think there would be a lot of average folks out there with TON of blown highlights if this were not the case. As a result, you must be a bit savvy to this and to use the histogram knowing how the camera reacts and that there is a ton of digital data to the right that would be a good idea to capture.

However, I just cannot imagine for the life of me why anyone would be using neg EC in the digital world.

sandpiper wrote in post #16202512
...I have used negative EC on many occasions, whilst still shooting to the right and having my histogram right over to the right hand edge.

My comment: could you please, for my educational purposes, provide an example of one of these times?

....ETTR is a good technique, but you can't just blindly set +ve EC and leave it regardless of the subject and background. It is still up to the photographer to decide on the settings to use (whether +ve or -ve compared to the meter reading) even when shooting to the right....

My comment: Exactly, well stated

idsurfer wrote in post #16202574
However, I just cannot imagine for the life of me why anyone would be using neg EC in the digital world.

could you please, for my educational purposes, provide an example of one of these times?

Yeah, sure.

For starters, there is that one I put in the post about the white bird against a dark background. Using evaluative metering, the camera will read the dark background and try and set an exposure to make it a medium grey tone, which may be lighter than the background so the camera will be overexposing. But the white bird in the sun (perhaps an egret fishing) would need much less exposure than the dark background to be correct, using the meter reading the bird will be horribly overexposed and the white will blow out, leaving a totally featureless bird shape in the frame, with no detail on it. In order to keep all that lovely feather detail, you need to reduce the exposure by using -ve EC.

For another, shooting racing cars on a sunny day a little while back, I was shooting mainly at O EC, which was great for most of the cars, the DR of the scene had my histogram pushing the edge of the scale at each end, and exposures were great. However, some of the cars were white (or had large areas of white on them) which reflected the sun and using the same settings meant that the white paint totally blew out - looking at the blinkies and the histogram, the cars were just huge great flashing black areas. I ended up reducing exposure to 2 stops below the meter reading (effectively -2 EC, but I was in manual) to keep detail in the bodywork, but even then there were small patches blowing out according to the histogram and blinkies (although most of that was recoverable in raw conversion, with just odd spots still blown out, which I could live with). The background etc., was heavily underexposed but I aim to get the exposure right for the subject and deal with the background later if necessary. Using that same -2 exposure on a dark green car though would have given a very underexposed subject. What I ended up doing was shooting the white cars for a couple of laps, then adjusting exposure and shooting the others for a few laps. Sometimes you just need to underexpose the shot as a whole, in order to stop critical whites blowing out. I have had to do this with various subjects. Ideally, you should place the white subject in the shade and reduce the sunlight that is blowing them out. That is easily done with a bride, for example, but race cars on a track? Birds on a sunny branch? white sails on yachts? not easy to move them to another, shadier, location, in fact usually pretty damn impossible.

Imagine shooting a black cat, and then a white cat using the spot meter to read the exposure from the cats fur. In both cases the meter will try and expose to reproduce them as grey (traditionally 18% grey, but that varies a little according to camera). Shoot both at the meter reading, in other words with no EC adjustment, and both cats will come out grey and look essentially the same. You need to add +ve EC to the white cat shot, to increase exposure and bring the grey back up to white, and add -ve EC to the black cat shot to reduce the exposure and bring the grey cat back to black.

I don't use -ve EC most of the time, but there are times when it is necessary to hold detail in the whites, or even to get a black subject against a dark background correctly exposed.

There has been a ton of really good info here but I'd like to say that I would hope the guy that drops $4000 on a 5DIII body, more with lens, would know he might have to make some changes to capture a white bird against a dark background.

idsurfer wrote in post #16200642
Ignore the numbers, use the histogram, compensate as needed and you will be fine.

This really is very sound advice.

It is hard to imagine completely relying on the camera's meter . . . ever. Additionally, even if the meter was always "right", every scene can be different in terms of how you want to expose it.

Exposure is a creative choice, and how you expose an image will depend on what latitude you have to make changes when you are editing it.

Expose each and every image exactly the way you want that particular image to be exposed, dependent on what you want the final image to look like. The histogram is the most accurate way of monitoring your exposure on an image-by-image basis.

Thank you Sandpiper for taking the time to write that up. I have a feeling I am doing a lot of this by nature without even knowing it. I make exposure decisions on the fly using the knowledge I have of how the camera is going to react and based on what it is in the scene I want to be perfectly exposed. Many times, when shooting Av and using EC, I will simply switch to spot metering and go from there. In this case, if you spot meter the white cat against the black wall, you will still end up with a +EC in order to keep it from coming out neutral grey. I guess this is why I never find myself dialing in -EC. Clearly there is more than one way to skin that white cat! Seems as if the thing that needs be clarified when discussing exposure settings and EC is what metering mode one may be using. Thanks again.

John from PA wrote in post #16202710
There has been a ton of really good info here but I'd like to say that I would hope the guy that drops $4000 on a 5DIII body, more with lens, would know he might have to make some changes to capture a white bird against a dark background.

Unfortunately there are a lot of rich people in the world who think that buying the best gear will make them a good photographer. Not saying the OP is in this category by any means, but I guarantee you probably one person per day buys a 5D MkIII and only knows how to use it in Auto mode.

Don't forget the histogram is based on the picture style set in camera.
It doesn't seem to make a huge difference if shooting raw, but it can mean that the raw file doesn't always reflect the camera histogram.

For what it's worth I find imagers shot using the same settings on my 650D look slightly brighter.