Exposure Compensation

[Canon-Fodder!]

How about a full & definitive "How, When, Where & Why" to use Exposure Compensation ?

Despite having read, re-read & re-re-read the Bryan Peterson book "Understanding Exposure" I continue to find myself in situations where I just don't get it right !

A decent treatise on the subject (I think) would be beneficial!

[Papathanassi]

Re: Exposure Compensation

Hello Canon,
I have also read the book Understanding Exposure, the page that is the most informative is from memory 43? It goes like this,
Purchase a grey card, you only need to use it once!
If you're ever in doubt about any exposure situation, meter off your hand.
You'll need to calibrate your palm, first. To calibrate your palm, take your camera and grey card into full sun, and set your aperture to f/8. While filling the frame with the Grey Card, adjust your shutter speed until a correct exposure is indicated.

Now, hold the palm of your hand out in front of you. The camera's meter should indicate that you're about +2/3 to 1 stop overexposed. Make a note of this.

Then, take the grey card into open shade, and again meter your camera's aperture at f8 and again adjust the shutter speed to show correct exposure. Again, meter off of your hand, and you should again see that the exposure is +2/3 to +1 stop overexposed from the reading off of the grey card, the same as it was in sunlight.

So, you now know that taking a reading from the palm of your hand gives you (either) a +2/3 or +1 overexposure.

If this doesn't work then the subject is probably outside of the Camera's capability's recording range? Hope this helps.
Papa.

[Papathanassi]

Re: Exposure Compensation

Forgot to say the Camera should be in Manual mode to calibrate your reading for your card and your hand.

[Millie]

Re: Exposure Compensation

How about a full & definitive "How, When, Where & Why" to use Exposure Compensation ?

You want definitive answer. :-)
That’s the trouble with photography, most of the time you can only give a definitive answer for a very specific scenario.

Provided you are happy with your metering and the camera’s got it wrong.

Longer shutter speed “positive compensation” when the histogram /LCD shows the image is too dark

Shorter shutter speed “negative compensation” when the histogram/LCD shows the image to too bright.

Exposure compensation is just a term some that some people find easier to ‘get their head around’ than increasing / decreasing their shutter speed.

There are some times when using semi auto modes with exposure compensation puts you at a distinct disadvantage.

Example: in constant lighting conditions, and were you haven't got time to be doing a lot of chimping. :-)

Millie

[briansquibb]

Re: Exposure Compensation

Shoot in RAW and adjust afterwards?

[Canon-Fodder!]

Re: Exposure Compensation

Hi Guys;

Yep - I'm aware of all of the theory, and try my best to "get it right", but I still think this would be a good topic for "Future Content" which is the point of this thread...

I do shoot RAW exclusively, and yes, you can adjust to a certain extent, but the finished product is still not as good as it should be if you get it right in-camera first-time...

[laurie]

Re: Exposure Compensation

just bracket the shot and pick the best one

[Trevoreast]

Re: Exposure Compensation

just bracket the shot and pick the best one

Laurie, I wonder if that is some kind of genre specific suggestion. ie relatively static - landscape or architecture ?
I think there are a lot of situations were the "correctly" exposed snap is not necessarily what you wanted in terms of content of pose.

Trev

[colin C]

Re: Exposure Compensation

The Histogram is your best friend in photography, so look in on him regularly and he'll always help, even if it's just to confirm you have it right..

We've had two useful suggestions so far, of correct in RAW afterwards and bracket the shots, but they both have their flaws. Correcting in RAW will generally get you out of trouble, but if you have clipped either side of the histogram, there is nothing RAW can do to restore detail in the whites, or unblock shadows. Also if you have ever got the exposure badly wrong and tried to correct in RAW, the end result often looks overworked. Bracketing is fine for a landscape, or still life, but once you introduce movement, then each shot must be different. You will end up with the best exposure amongst them, but you have also just increased your workrate by the same factor of your bracketed number.

You can read all the books on exposure that you want and they will always give the grass and skintone tip, but do they advise you to do the skintone test before and after you go on holiday? A decent suntan can easily upset your calculations.

Experience tells you when to rely on the camera and when to compensate and a percentage of experience is that you have previously made those mistakes. Failing that, we are back to the Histogram. Shoot in Raw and regularly look at the Histogram. If the tonal range is within the histogram and not clipped at the edges, you are doing fine. Generallly try to keep the mountain in the middle, but I now shoot slightly to the right, as it keeps high noise shadow detail cleaner. If it clips the right (highlights), dial in some -compensation. If it clips the left (Shadows) dial in some +compensation. Take another shot and keep going with the compensation until the clipping disappears.

Get used to the Histogram and you won't go far wrong. There is a also certain satisfaction of getting it right in the camera rather than correcting the shot afterwards.

Colin

[briansquibb]

Re: Exposure Compensation

I have found that for candid shots the exposure lock is my best friend. I use spot metering so before composing I point at the part I want exposed correctly (say the face for example) press the exposure lock button (in my case the *) and then compose. At a wedding, for example, I would be using the white wedding dress to get the exposure

I find now that I can do this pretty much in a single action so I dont miss the shot. This also works the same with the flash mounted

[Trevoreast]

Re: Exposure Compensation

There is a also certain satisfaction of getting it right in the camera rather than correcting the shot afterwards.

I agree Colin, there is great satisfaction in getting it right. In some cases it can mean the difference between spending precious time, rescuing a careless snap, and tweaking a good image to improve a bit.

Getting the exposure right in the camera is one of my top priorities. I'm Not saying I always acheive that.:-)
You can introduce all sorts of negative effects in PP.
That's one of the main reasons we see so many noisy ISO 400 shots in adequate light from people using the latest cameras like eos7D that have excellent high ISO capability.

When they say x camera is capable of very usable "noise free" images at ISO 1600, what they don't tend to mention is that they're talking about images correctly exposed in the camera, not snaps that require significant doctoring to produce a passable 800px image for web display.

Imho the ideal skill set would be to consistently “get it right in the camera” and have good PP skills..
Lacking in either or both of these different, but interlinked skills, can lead to dodgy results, in short a waste of time and money, if money’s not an issue and you have "time to kill, that's different.

I'm just saying what's true for me, other people experiences and opinions will differ. :-)

Trev

[Trevoreast]

Re: Exposure Compensation

I have found that for candid shots the exposure lock is my best friend. I use spot metering so before composing I point at the part I want exposed correctly (say the face for example) press the exposure lock button (in my case the *) and then compose. At a wedding, for example, I would be using the white wedding dress to get the exposure

I find now that I can do this pretty much in a single action so I dont miss the shot. This also works the same with the flash mounted

Have you got a 1 series body now ?
As far as I know only 1 series bodies have separate button for flash exposure lock (FEL) and one for normal ambient exposure locking.

On other non 1 series bodies with the flash mounted and turned on the exposure lock button becomes the FEL.

Also may be worth pointing out; for those who normally shoot in manual mode were practical.

Exposure lock is only available when the camera is in auto or semi auto modes. Same with Flash exposure Lock - it’s only available with the flash on auto – (ettl) if you prefer.

Hope this helps you Brian :-)

Trev

[briansquibb]

Re: Exposure Compensation

Yep, as I said the * button works as exposure lock and flash too - means I dont have to think whether flash is on or off - always the same button so quite instinctive

I shoot candids in AV mode and fix the shutter speed with the exposure lock (semi manual mode?). Same with the flash, ettl is the only way to go for action pictures.

[Trevoreast]

Re: Exposure Compensation

Yep, as I said the * button works as exposure lock and flash too - means I dont have to think whether flash is on or off - always the same button so quite instinctive

The key point is that when the flashgun is turned on a non 1 series body.
The * exposure lock button becomes the FEL button provided the flashgun is in ettl mode.

It’s very important for people to be aware of this, and it’s implications, if they’re not it can have a profound and potentially negative impact on exposure consistency. That’s the reason I mention it. :-)

Trev

[EOS_Jim]

Re: Exposure Compensation

I have found that for candid shots the exposure lock is my best friend. I use spot metering so before composing I point at the part I want exposed correctly (say the face for example) press the exposure lock button (in my case the *) and then compose. At a wedding, for example, I would be using the white wedding dress to get the exposure

I find now that I can do this pretty much in a single action so I dont miss the shot. This also works the same with the flash mounted

Can you confirm what you mean Brian because this is exactly where you should be using exposure compensation or you will under expose the shot.

If you spot meter the dress and lock that exposure and take the shot, the dress will be around 1-2 stops too dark because the camera will meter that as a mid grey. The best way to shoot using a spot meter of a mid grey and you should get a good exposure or shoot a specific target as mentioned above (like a hand or other known consistent tone) and use EC as required. A spot meter does not remove the need to use Exposure Compensation.

The camera's meter is pretty dumb.

Like colin says, the histogram is your friend.

Personally I shoot in Manual and use a handheld incident meter that gives me an accurate exposure for most of my portrait shots. there is no guess work required (other than what to meter for - i.e. highlights or shadow) Shooting in Manual also means no need to think about exposure compenstaion as you do this by setting the correct exposure for what you want.