Well, what I believe, do not think the camera is nothing wrong, the inconsistency in the color yield is almost certainly due to a wrong white balance (White Balance).
I am convinced that the White Balance is the first thing a user of digital camera should learn, this single issue, learned and executed correctly, will make a big difference with the pictures of those who have not mastered.
Here comes the explanation: the light is not a constant color, not all light sources are the same color, the color of light is different at dawn, noon and evening, but those colors vary according to the height at which we are, it is not the same as a half day at sea level, a half day in the Andes, over 3,500 meters (at sea level the light passes through a thicker layer of atmosphere .)
Nor
light of our artificial light sources is the same tungsten incandescent bulbs give us a "warm glow" (yellow), while most fluorescent give us a "cold light" (white). The candles for instance, have the charm of warm light and cozy, while the white fluorescent give us the feeling of clinic or office, uninviting.
So we can understand that the color of light is essential to get the effect you want in a photograph, and the mishandling of the color of light that we can ruin a photo could have been excellent.
To complicate our lives, scientists refer this color of light as the temperature of the light "giving low values \u200b\u200bof temperature warm light and high values \u200b\u200bin the cold light. This temperature is measured in degrees Kelvin (actually in Kelvin), and here we see an example, and as we noted, the white or neutral light is around 5.500 kelvin ...
Kelvin temperature of light in
Neutra? ... how they neutral? ... neutral with respect to what ... this is where demystify and simplify the issue of temperature of light neutral = white , warm = yellow, blue = cold .
Even saving bulbs, you can read on their packaging if the light that will illuminate us is warm (low temperature) or cold (high temperature), see ...
This is the packaging of a light bulb warm = 2.700 K
a cold light source = 6.500 K
Let's put things in perspective: warm light = yellow light, cold light = light blue. So this issue of getting the right colors in a picture, regardless of the light source to use is only a matter of avoiding the photos we go yellow or blue, is a balance between yellow and blue, having that perform the corresponding actions for the balance.
The opposite of blue is yellow and vice versa, and to balance blue excess we must put more yellow, and excess yellow need to put more blue.
And where is most evident if our colors are unbalanced? ... in white, which is why the action of getting a correct white balance is called White or English White Balance. Thus, if our light is yellowish (warm), we need to put a little blue (cool) to balance it and make it white, and if our light is blue (cold), we need to put some yellow (warm) , to neutralize the blue (swing), and that is white ... means?
If our target is really white, then automatically all the other colors correspond to reality without any yellow or blue patina.
Let us see what the manual says a digital camera:
Extracted from the operating an Olympus E-30 (click to enlarge )
According to this table we see that the AWB (Auto White Balance), only works if the scene is a significant portion white for the camera to take it as a reference. In other words if there is a portion of white on the scene framed in the viewfinder, there is no automatic white balance and the result is totally random, this is a primary source of inconsistency in color reproduction.
Then we see that daylight, Olympus fixed temperature 5.300 K (white light), but if we are in a sunny day at noon, and we are in the shadow (shadow) , hence the light temperature will be about 7.500 K. is quite blue. Now, if we are on a cloudy day (overcast) temperature is 6,000 K, ie, blue but not so in the shade.
So when we use the correct light temperature in the menu on your camera, ie not use the automatic balance, the camera introduces, in the case of high temperatures or rather blue, different amounts of yellow, to counteract the excess blue.
Also, if you take pictures indoors under incandescent (tungsten), whose color is warm, that is yellow, the camera will compensate for the excess of yellow blue introducing to offset or balance.
In this way we can fool the camera when shooting a sunset, setting the menu that we are in the shade, the camera automatically compensate for the apparent excess of blue with a yellow patina, which we get the effect ayur yellow-red sunset postcard.
For cameras that have it one of the most useful in terms of white balance is the last item in the table above, for now memorízenlo that in a moment I will explain.
The following is a point & shoot camera for my daughter, is a Lumix DMC-LZ8, with which we to take a series of photos with different settings of white balance.
Lumix LZ8
AWB (Auto Balance)
Daylight ( daylight)
Overcast (cloudy)
Shadow (shadow)
Tungsten (incandescent)
Custom White Balance (custom)
This is what I told them to remember it, look well
Simble to find it in their cameras
Well, the photos I took around noon, so it is very likely that shadow and see something yellow overcast scene, while tungsten see the same scene, something blue:
Click to enlarge
Here you can appreciate and effect of different settings
to balance the white.
Everything went as planned, Overcast and shadow offset by excess yellow tugsten blue offset by excess to counteract the apparent excess of yellow, daylight car and did very well, being the scene of daylight slightly warmer.
Well, the last one? ... that says Custom White Balance? ... well, that is what should more accurately represent the colors of the scene, not all cameras have this feature, but for those that do, what they need is a sample of neutral white or gray to 18% in my case I have a specialized tool brand Lastolite , and his name is EzyBalance :
Greycard & Whitecard collapsible
On one side is a gray card of 18% reflectivity (Standard)
On the other hand is a neutral white card
Both sides used to the white balance is Show them is the camera which is white or neutral gray to 18% under certain lighting conditions, this is the most reliable and with better results, the white balance if your camera has this function .
"show" Camera what is real white
There are other tools for these purposes, such as ExpoDisk , Lally CAP, Spyder Cube and some other devices similar, but with the same objective, the white balance correctly, one of the best, along with ExpoDisk is card WhiBal , and these are the Instructions for use .
EYE! if you do not have anything at hand, can use a piece of white paper or cardboard, although not ideal, as this does not guarantee a neutral white is better than nothing.
In my particular case, the automatic white balance works surprisingly well, since I have an Olympus E-30 with one very simple and very clever at the same time. Has a temperature sensor light that works surprisingly well.
However I always prefer to do my white balance, and that the final effect makes the difference with no do:
Olympus E-30 with the temperature sensor of light.
temperature sensor light
This sensor is constantly "watching" the color of ambient light to make the appropriate balance, they still prefer to do on my own.
And to end this issue, we go to an extreme case, a night shot in a park lit by high-pressure sodium (not my fault, they are called), I mean those yellow lights with street lighting poles: first a photo taken with the camera set in daylight, tungsten and then custom and finally, using my EzyBalance .
With the camera set to daylight, she hopes to white light, so the sodium light poles is as it is totally amber. Note that the light of the urn is about 5.500 K, which is why she goes white, the right color expected by the camera.
When setting the camera to tungsten, thatis to incandescent bulbs, she compensates with blue, but based on a common source of home, being the more sodium light yellow, the amount of blue is not enough to make the right balance, so we still have too much yellow. Now the light of the ballot box is no longer white, it is blue, but she is really white, offset by blue camera to try to balance the yellow.
Using EzyBalance, and under the same lighting conditions, now the colors are correct, in exception of the light from the urn who now accuses the blue excess is necessary for offset the yellow. The light pole in the center of the picture, now if it appears and white colors of the park which now are correct.
can also use a gray card (18% gray card) in the post process, enter here:
OJO! theory currently exists for digital photography what neutral gray is correct 12% instead of 18% as photometers are not 18% in any case also is starting to gray market cards to 12%. I have not yet been tested, but if it works better, I will make the change.
Hoping again that this post will be useful I say goodbye until the next publication.
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