Use of Exposure Compensation

[Mark_48]

How many of you are using Exposure Compensation (not FEC) in your every day shooting? And once you've set it do you tend to leave it alone or make adjustments depending on the subject lighting? I find that with my 20D I'm setting the EC to about +1 to get good all around exposures and at +1 the exposures are about same as when I shoot manual using a Gossen light meter in incident mode. At EC 0, most shots just seemed underexposed.

Is the EC a way for manufacturers to take into account variances in sensitivity of metering or sensors?

[apoh]

i use mine alot in Av mode in conjunction with the histogram to see which way i want to shift it. sometimes in tough lighting situations i might actually underexpose to increase the shutter speed. really, it's no different than shooting in manual, except i think it's faster and more convenient.

the problem with using exposure comp is i often move around and forget to switch it back to neutral, causing more problems later on.

[Paul_O]

I shoot mainly in Av mode and only occasionally use it when I have contrasting subjects vs background say a white bird on the water or in the sky.
Ditto with apoh, forgetting to return it 0 is one of my most common errors!

Paul

[Chazs]

Since I got my 20D a few weeks ago I've shot about 95% of the time in full manual mode and compensate whenever and however I feel. It makes more sense to me to be in control of everything (even focusing, since I usually have an Olympus lens on it). On my DRebel I used exposure compensation a lot; not sure why my mindset changed with the 20D. I guess it's like buying an expensive sports car; I'd rather have a stick shift than an automatic.

[jfred]

I gravitate towards EC of +1 in a lot of situations

not sure why - I tend to look at the histogram and the LCD picture display to see what "looks right"

Would love a "reset to 100 asa and no EC button" or for that to be the default state on power-on though (some people are never satisfied!)

[robertwgross]

Mark, are you shooting RAW files?

---Bob Gross---

[Jim_T]

Like most of the camera options.. I use it as required :)

EC is meant to override the camera's exposure choice in unusual lighting situations. Most of the time you don't need it. If you shoot in full manual, then you don't even have the ability to adjust the EC. A quick glance at the histogram will let you know if you need it.

I use it most when shooting in bright situations.. (ie cloudy days with fresh snow on the ground or trying to shoot a small dark object against a bright sky).

If you're an image processing junkie, you could force the camera to underexpose a bit in all shots to eliminate the chances of blowing out any highlights.

Edit.. I have the 10D, which might (but shouldn't) meter any differently than the 20D.. For most of my shots, I don't use EC at all.

[Mark_48]

Mark, are you shooting RAW files?

---Bob Gross---

Haven't tried that route as of yet. Still getting my feet wet with alot of the basics of the 20D. What I'm hoping to do is achieve a good understanding of the settings on the camera to get me in the ballpark of good exposure so I can minimize tweaking of the EC during a shoot and reduce manipulation of many images after the fact.

The histogram has been a good tool, but if you take a one time shot and you don't like the histogram, it's tough to tell the bride, "Could you please toss the bouquet again, I have to adjust my exposure comp." So I'm hoping to find a sweet spot for the EC setting and not have to mess with it much.

[robertwgross]

Yes, I always found the bouquet-toss to be a tricky shot, but not for reasons of exposure compensation. If the bride is still wearing a white dress, then it might be important. But, if you have been shooting a white dress for the last three hours, you'll probably know to set it to +0.5 or +1.0. Sometimes the bride has changed into something different by then, so the white dress problem goes away.

Snow is the only thing that I really have to get right for exposure compensation. I shoot in snow a lot, so I have kind of figured out snow that needs +0.5, +1.0, or +1.5.

---Bob Gross---

[johneric8]

Yes, I always found the bouquet-toss to be a tricky shot, but not for reasons of exposure compensation. If the bride is still wearing a white dress, then it might be important. But, if you have been shooting a white dress for the last three hours, you'll probably know to set it to +0.5 or +1.0. Sometimes the bride has changed into something different by then, so the white dress problem goes away.

Snow is the only thing that I really have to get right for exposure compensation. I shoot in snow a lot, so I have kind of figured out snow that needs +0.5, +1.0, or +1.5.

---Bob Gross---

Robert when you say +0.5, +1.0, or +1.5. do you mean you open up the aperture to let in more light? So if you meter on the snow and it gives you 1/125 F16 you will change it to F15 or a something wider then F16

[robertwgross]

Robert when you say +0.5, +1.0, or +1.5. do you mean you open up the aperture to let in more light? So if you meter on the snow and it gives you 1/125 F16 you will change it to F15 or a something wider then F16

I mean that I set the Exposure Compensation to +0.5, +1.0, or +1.5.

Now, what does that mean?

It means that the meter reads something, and we will call that 0.0. The Exposure Compensation system changes the values put into the shutter and/or aperture so that it will be brighter than what the camera would have done automatically for 0.0.

Exactly what value it modifies will depend on whether the camera is in Tv or Av or whatever.

When the normal metering reads the scene, it assumes that everything will average out to 18% gray, so it meters and then sticks the solution into the shutter and aperture. The normal metering tends to get it so that white snow looks about 18% gray, which is not your intention.

However, if the trained photographer's eye-brain says "You know, I think that snow is too white." You crank up +1.0 or whatever in EC, and then a slightly different set of shutter or aperture settings go into the shot. As a result, the snow will be brighter, closer to what you intend. If you go too far, you will blow out the white, and that is overdone.

So, I am not thinking about changing a shutter or aperture from one to another, but the camera is doing something like that when it reads my EC.

---Bob Gross---

[pyterps]

I think what everyone here is talking about is the zone system. I have been reading it a lot and starting to you it on some B&W work and has helped me understand exposure and looking at what is being photographed.

Dave

[BoySpot]

Photographing aircraft against the sky can be a good time for EC usage. A blue sky may only need +1.0 but if it is cloudy, it can be worth going up to +2.0. I tend to calibrate my requirements by comparing with some metering of ground based subjects and working out the EC from there. If that's not possible, then the above guesses are often close enough. RAW also helps salvage slight innaccuracies. The histogram is not a lot of help in these situations. You don't have a good spread of tones and can get a very peaky histogram, even when the exposure is just what you want!

[robertwgross]

RAW also helps salvage slight innaccuracies.

I think that is the major advantage of RAW.

If you can hit the perfect exposure right every time, then go do JPEG if you want.

For the rest of us mere mortals, we'll get exposure close 98% of the time. RAW helps tweak that in before we get out into JPEG land.

---Bob Gross---

[CyberDyneSystems]

Clearly it depends on the shooting conditions... it can certianly vary dramtically.

But I almost allways have plus 1/3 or more.. I find both 20D and 1D mKII expose a little "safely" towards the low end.. and need more plus EC...

Oddly I found my 10D to be more likely to find the happy middle gorund,. if anything, tended to overexpose and thus need -1/3 or more in certain conditions.

[BrianCerveny]

If you can hit the perfect exposure right every time, then go do JPEG if you want.

For the rest of us mere mortals, we'll get exposure close 98% of the time. RAW helps tweak that in before we get out into JPEG land.

---Bob Gross---

I use RAW+JPEG for most of my shooting. It's like getting the negatives along with your prints in the olden days. ;)

[who me?]

I use it most when shooting in bright situations.. (ie cloudy days with fresh snow on the ground or trying to shoot a small dark object against a bright sky).


Jim, on this comment, If you are shooting a hawk against a blue or grey sky, how much do ou compensate? I tried this last weekend. Shooting a flying hawk against a grey sky. 20D, 100-400 at about 350, hawk size was about 25-40% the size of the frame. Center focus point and centerweighted metering and tried +1/2 stop and I still got basically a sillouete. I don't remember the F-stop or shutter speed. Any suggestions? Thanks.

[Tapeman]

If you live in the snow belt, you will over expose a lot during the winter if you want your snow to be white. (Although that may be a carry-over from shooting film.)

[CyberDyneSystems]

Who me,

1/2 stop won't be enough usually in those situations,. especially "centerweighted" with Partial metering (smaller "spot") you would want a 2/3rds to a full stop at least usually,.

[mjordan]

I shoot in AV mostly as well and use EC all the time. I normally keep it about +1/3 to +1/2 on my 10D because that seems to be what it needs. I also EC for bracketing when I have backlit subjects and I plan on taking a normal exposed forground and a normal exposed background and merge them in Photoshop. It's a lot quicker to take a picture, roll the wheel, take a picture, roll the wheel, etc. when I need to go up and down a stop or two, especially if I'm on a tripod and I don't want to move the camera off the focus point.

I also shoot raw 99.9% of the time (I can't remember when I shot jpeg last, but I'm sure it's in that .1% somewhere :D ).

Mike

[Jim_T]

Jim, on this comment, If you are shooting a hawk against a blue or grey sky, how much do ou compensate? I tried this last weekend. Shooting a flying hawk against a grey sky. 20D, 100-400 at about 350, hawk size was about 25-40% the size of the frame. Center focus point and centerweighted metering and tried +1/2 stop and I still got basically a sillouete. I don't remember the F-stop or shutter speed. Any suggestions? Thanks.

In the summer I have lots of red tail hawks around where I live. I've never manged a good close shot where they filled a substantial part of the frame.. Even when they're soaring, they always see me and fly away.. They're hard to sneak up on. I guess because they have eyes like hawks :)

With a blue sky, I usually don't compensate at all.. Maybe +.5 now and then. If the image is a bit dark, it can be brought up with levels..

Cloudy skies I hate :)

You can bump the EC to +1 or +2, but I've never been happy shooting birds against a cloudy sky.

I always switch to RAW when shooting wildlife.