En la web hay demasiados tutoriales, posts en foros y comentarios plagados de falsas ideas sobre la fotografia HDR, he juntado una pequeña coleccion de mitos populares que creo conveniente aclarar.
Myth # 1: Single RAW HDR can not be a
An HDR is but a graphic format, like a JPG, a TIFF, a PNG and many others. The difference is that where a JPG has a depth of 8 bits for the brightness and has a 16-HDR Tiff has 32 or 48 and uses floating point values \u200b\u200binstead of integers, is said to have practically unlimited capacity values light in each pixel. Many people postulates "that's not a HDR", "fake HDR" or "pseudo" HDR "when the reality is that anything that creates an HDR is an HDR. If it makes sense or not make an HDR from only 1 exposure of 3 or 29 is another matter.
In short, "An HDR is an HDR is an HDR"
Myth # 2: With 3 exhibition in bracketing always reach
This is extremely popular to the point that in many places postulated "to be drawn HDR 3 exposures." The number of exposures needed depends on the dynamic range of the image, there is greater contrast between highlights and shadows need more number of exposures. The 3 exposures typically up to 80% of the scenes photographed but for the remaining 20% \u200b\u200bmaking a grave error if you only take 3 photos. Scenes such as a tunnel to the outlet and near total darkness lit inside can require more than 20 exhibitions to capture the full dynamic range of the scene.
A convenient way to expose your high beams is measured in timely, expose for the bright lights in manual mode and then gradually increase to one or two stops until the shadows are exposed in sufficient detail. This will give the number of necessary shots.
Myth # 3: The more exposure better
Another popular myth, many pages I read "A buenisimo HDR, use 9 exposures" when in fact they should speak of "A nightmare, I had to use 9 exposures." As we increase the number of exposures to assemble an HDR a series of bad things happen. The noise increases, the errors of trepidation or movement of the camera are maximized, there are ghosts in anything the wind can be moved as leaves, water, etc. Besides the algorithm that generates HDR is more likely to make many more bad things to choose from different exposures to a single pixel, remember that the algorithms that generate HDR are good but not smart. Ideally
get the minimum amount of exposure needed to capture the dynamic range of the scene is that the histogram does not touch the left edge takes more overexposed and does not touch the right edge in making more subeexpuesta.
Myth # 4: HDR night out loud
As with any photo if one is noisy HDR is usually the cause underexposure.
abound in a night scene, as expected, the shadows and dark areas. It is essential over-expose these areas due for a HDR to capture detail in place to capture noise. Bracketing mode -2.0, +2 is often wholly inadequate at night, in three exhibitions it is best to -1.1, or 0 +3, +2, +4 but we recommend you discuss the scene properly and make as many exposures as it takes. We can start with 0, +2, +4 and then if you add a shot high beams at -2. Or we can start with -2, 0, +2 and add an outlet on +4.
is true that the tone-mapping process usually increases the noise but if the signal (amount of light) is strong enough not be a problem in the final image. In short night
is heavily overexposing.
Myth # 5: Can not do HDR without tripod
I would like to say that this is true but in reality is a myth. If the scene has enough static and little motion alignment algorithm that generates HDR software is usually good enough to achieve a good alignment of the exhibitions. It is obvious that if we have a tripod there is no reason to take risks.
In short: We will not make a HDR without tripod (to be)
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