Control exposure and dynamic range

Controls exposure and dynamic rangeControlar la exposición en fotografía cuando hay mucho contraste

One of the main problems when we take photos with natural light and there is a lot of contrast is the dynamic range. Thus, one of the main objectives of this type of photos is to control exposure and dynamic range .

Okay, but … What exactly is the dynamic range?

The dynamic range in photography:

The dynamic range of any device, object or medium represents the amount of signals it is able to distinguish, capture or represent.

The greater the number of interpretable or reproducible signals by the device, the greater the dynamic range of the device. At lower dynamic range there will be fewer opportunities to show or interpret these signals.

OK, but I’m a dummy , and I have not understood this concept. Can you simplify it? Could you tell me what it is used for in photography?

With the intention of simplifying it, adjust it to the medium and answer my questions (I put myself in the role of dummy) I will try to expose a few lines below what for me means the dynamic range in photography .

The diaphragm steps that our sensor captures:

The dynamic range in photography would be what the sensor of our reflex camera is able to interpret when making an exhibition if we consider only the shadows and highlights of the photo in question.

Simplifying even more (and taking into account the exposure meter of your camera). The dynamic range will be the difference in diaphragm steps between lights and shadows.

In other words, the dynamic range is the interpretation of the light of the scene by the sensor of our camera.

Maybe you’re wondering, do the cameras interpret our eyes differently? The answer is a resounding yes, and not only regarding the dynamic range.

To take into account about the dynamic range:

Now that you know the existence of dynamic range (if you did not already know) you will explain why the photos you did not know because they had been that way.

From now on you will know that your camera will not be able to interpret all the information that your eyes process in a broad and precise way .

Yes, our view far exceeds the dynamic range of any camera. In fact, cameras mimic the behavior of a human eye .

Taking advantage of the dynamic range to our interest:

Luckily, this sensor limitation of our cameras can be used at interest. I was wondering what would be the low-key photos … Well, something would invent safe.

The dynamic range is a limitation of our photographic equipment , but like almost everything in life, it can be used at will to personalize any photograph taking into account this limitation and take advantage of it.

I have given as an example a portrait illuminated by the low key technique, but there are many more options that you can see in this photography blog .

I have written a lot of articles that, without mentioning the dynamic range, make direct reference to this limitation of the sensors of the cameras.

The dynamic range of the example photo:

The example of architectural architecture that accompanies this article was made in the summer of 2012 in the Alcazaba de Málaga . It was midday and the main technical difficulty involved in making this picture was precisely to control the dynamic range.

If you notice, you can approach the time of realization by angulating the shadows projected by the tiles, just above the windows that appear in the photo.

There are details in all parts of the histogram, right and left and also in the center.

Reviewing the exif data of this photograph I can see that I used a diaphragm aperture of F16 , an ISO 100 speed, a shutter speed of 1/80 seconds, a custom scene mode and an automatic white balance, the focal length was 28 millimeters The equipment used was a Canon Eos wide-body camera body together with a 28-80 F2.8 AT-X Pro lens from the Tokina brand.

So, you can get an idea of ​​how I used the dynamic range to control the exposure of this architecture photo. Do not forget to ask if you have questions.

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