What is real HDR?
In image processing, computer graphics, and photography, high dynamic range imaging (HDRI) is a set of techniques that allows a greater dynamic range of exposures (the range of values between light and dark areas) than normal digital imaging techniques. The intention of HDRI is to accurately represent the wide range of intensity levels found in real scenes ranging from direct sunlight to shadows.
High Dynamic Range Imaging was originally developed in the 1930s and 1940s by Charles Wyckoff. Wyckoff’s detailed pictures of nuclear explosions appeared on the cover of Life magazine in the mid 1940s. The process of tone mapping together with bracketed exposures of normal digital images, giving the end result a high, often exaggerated dynamic range, was first reported in 1993, and resulted in a mathematical theory of differently exposed pictures of the same subject matter that was published in 1995. In 1997 this technique of combining several differently exposed images to produce a single HDR image was presented to the computer graphics community by Paul Debevec.
This method was developed to produce a high dynamic range image from a set of photographs taken with a range of exposures. With the rising popularity of digital cameras and easy-to-use desktop software, the term “HDR” is now popularly used to refer to this process. This composite technique is different from (and may be of lesser or greater quality than) the production of an image from a single exposure of a sensor that has a native high dynamic range. Tone mapping is also used to display HDR images on devices with a low native dynamic range, such as a computer screen.
So basically if you have a good camera what you should do is to take picture of the same scene ( you’d better use tripod, or make sure your camera does not move during shooting) with different exposures, lets say with 3 steps -1.5 EV , 0 EV , +1.5EV, or you can set your camera for saving images in RAW format which gives far more greater dynamic range! Then download and buy one of the software from the internet which will guide you through the rest of the process. These are Photomatix, Dynamic-Photo HDR and sometimes Adobe Photoshop Light Room for RAW images. Than it seems pretty simple, open your image(s) in software,align them ( if camera were shaking during shooting), correct the white balance, the color saturation, and than the most important : Tone Mapping. That is the technique which gives you unlimited creativity of increasing the Dynamic Range of your image, so it really depends on your goal! First of all HDR is great for sunsets, great landscapes which includes skies and clouds, and of course interiors! HDR can increase detalisation in black areas, give you more blacks in white spots! So take your camera and start practicing in a field!
P.S. Dynamic-Photo HDR software can make “fake HDR’s” with only one LDR( low dynamic range) image, so give it a try!
Do not miss reading the following two great tutorials / faq about HDR…
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HDR Tutorial by Stuck in customs
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HDR Tutorials, tips and tricks by Kirt Witte
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http://www.vanilladays.com/hdr
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