| Author | Thread |
|
|
08/29/2004 01:32:42 PM · #1 |
I had some problems yesterday with some over exposure. O.K. say the camera is in the shade and the subject you want to shoot is in the sun, what do you set your white balance to?
|
|
|
|
08/29/2004 01:37:58 PM · #2 |
| I would spot meter on the most sunny subject, and lock, then recompose and focus, but you shade will be under exposed. |
|
|
|
08/29/2004 01:53:10 PM · #3 |
Sun - the shade around the camera doesn't affect the subject, does it?
E
|
|
|
|
08/29/2004 02:50:45 PM · #4 |
Set the whitebalance to the light the main subject is in (the image could have both sunny and shady areas).
But whitebalance has little to do with being overexposed, that is another matter entirely. Digital cameras have a very limited range of stops (differences in light levels) that can be captured at once, anything over or under that range and you get over or under exposed areas in your images. When shooting a subject that has more stops of light range than the camera can capture you have to choose which you want most, the highlights or the shadows. Alternately you can take multiple exposures; say one for the highlights and one for the shadows, and then combine them in photoshop.
Some will tell you to base your exposure on the middle-tones of the scene, but unless you know the highlights will then fall within the range your camera can capture it is a bit dangerous. I prefer to set the meter bias to +2 stops and then meter the lightest part of the subject (may not be the lightest part of the scene). This prevents the highlights from being blown out, and as little detail will be lost to the shadows as possible. I use +2 since that is what I have found is what works best to get the histogram as far to the right as possible, while still maintaining a small margin to allow for post processing.
It was also recently pointed out to me that more dynamic range is available when in-camera sharpening and contrast are set at their lowest levels.
However, the best thing to do for outside shots is to get a polarizer filter as it will help much more than exposure tricks and techniques.
David
|
|
|
|
08/29/2004 03:16:52 PM · #5 |
Spot-meter with exposure compensation to suit on time of day/intensity of light. Bracket critical shots. Review with histogram on. Make adjustments as necessary. Reshoot.
I prefer to underexpose every shot taken between, say, 10 am and 2 pm on a bright day. Exposure can become a very personal and creative choice, at least after due care has been taken to retain detail in highlights.
|
|
|
|
08/30/2004 09:21:05 AM · #6 |
| YOu might try using a grey card. |
|
|
|
08/30/2004 09:30:14 AM · #7 |
Some of the strangest exposure advice I've seen in a while, but I guess whatever works for folks.
A meter (spot, partial, center weighted - excluding matrix for now) works on the idea of a mid tone. Meters have no concept of colour, just tonality, from black to white. Anything you point at in a scene will be metered as if it was a mid grey. If you expose at that value, or any related value due to reciprocity, you will get the thing you metered upon captured as a mid grey. If you point at something white, you want to overexpose by a variable amount, depending on how much brighter than the mid tone you want in your final image. If you point at something black, you want to underexpose by a variable amount, depending on how much darker than the mid tone you want that thing to be in your final image.
Pick the thing you care about the most. Meter on it. Compensate the result to capture the thing you care about at the right tone, relative to a mid grey and your own subjective choice. If you can't meter on the thing you care about, pick something else in the same light and place the exposure for it correctly, relative to what you care about.
That's it. That's all there is to metering and exposure.
Now, different meter modes vary the amount of the scene that is sampled to be considered 'mid grey' Spot takes a small spot, partial considers a small circle about 9% of the scene in the center, center weighted samples most of the scene but gives the most consideration to the middle.
The key is in the concept of 'variable amount' of under/ over exposure to add. Lighting can vary this quite a lot too. There are many good books on this subject - John Shaw's field guide would be a good start.
A polariser is not something to use to fix exposure issues, though it does have the side-effect of being a variable 1 to 2 stop neutral density filter, which lets you shoot more slowly if you need to, while often quite radically changing the colours and reflections in a scene.
White balance has nothing to do with exposure, just varying the overall colour cast introduced by the lighting in a scene. It should be set based upon the light the subject is in, not the light where the camera is. This is obviously problematic if you are trying to shoot a mountain in the distance as you cannot easily put a white target there. In such cases RAW mode or presets are useful. In mixed lighting situations shade/ sunlight there isn't really anything you can do other than pick the dominant light source. You will get a colour cast either warm (red) or cold (blue) in the area you don't select. Typically a warmer cast looks better for people.
Exposure compensation should be applied, depending on the thing that you meter upon, not just set once and forgotten about.
Matrix metering modes are somewhat akin to a lottery. Nobody knows what exposure value will get picked. Nobody knows if it'll be right or not. Certainly nobody knows if you should add or subtract exposure compensation. Usually, and in general, matrix modes will give you a resonablly okay, bland exposure choice. It certainly will get it wrong occasionally and certainly biasing the final result with exposure compensation is a recipe for random failures and frustrating results. I use matrix modes all the time when I have no creative interest in getting a good exposure. I never use them when I actually care about the exposure result.
Message edited by author 2004-08-30 09:34:01. |
|
|
|
08/30/2004 09:45:38 AM · #8 |
Originally posted by Gordon:
Exposure compensation should be applied, depending on the thing that you meter upon, not just set once and forgotten about. |
When I am shooting a bunch of cloudscapes or sunsets, I will often set the exposure compensation to -1/2 or -1 for the duration of the shoot, and meter taking that setting into account. I find that has the best chance of maintaining detail in the bright-white parts of the clouds.
I've also set it to -1 and forgotton about it and gotten a lot of underexposed shots : ) |
|
|
|
08/30/2004 10:10:29 AM · #9 |
(Spot) Meter on your brightest subject that you want to retain detail in, then meter again on the darkest region you want to maintain detail in. If there are more than 4 stops difference, chances are you can't take the shot well in that lighting. Exceptions are possible if you use either a neutral density or graduated neutral density filter.
Remember that no amount of matrix metering, "zone" methodology, or any other exposure selection algorithms will be able to exceed the exposure resolution of your sensor, and digital cameras are roughly a 4 stop capability. Your job as an atrist is to pick what part of the spectrum to display and know whether or not the excluded regions will detract from the final image.
Watch your histograms and do a lot of experimentation.
|
|
Home -
Challenges -
Community -
League -
Photos -
Cameras -
Lenses -
Learn -
Help -
Terms of Use -
Privacy -
Top ^
DPChallenge, and website content and design, Copyright © 2001-2025 Challenging Technologies, LLC.
All digital photo copyrights belong to the photographers and may not be used without permission.
Current Server Time: 08/05/2025 06:44:49 AM EDT.
