HDR or High Dynamic Range as Fast As Possible
Techquickie
·Techquickie
·2015-05-07
·
1,203 words · ~6 min read
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Let's start with an explanation of dynamic range since it's pretty likely
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that it'll be easier to understand what a lot of it is if you know what it is in
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the first place. Dynamic range is much like a contrast ratio, a measurement of
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the difference between the brightest part of an image and the darkest. Unlike
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contrast ratios, which use linear numbers to represent the luminance of
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the brightest whites and darkest blacks in an easy way that anyone can
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understand, dynamic range is measured in f-stops. Each of which represents this
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difference in powers of two. Okay, so let's do an example. A pocket camera
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rated at six f-stops of dynamic range can correctly capture an image that has
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bright spots that are 64 times brighter
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than the darkest shadows. This, according to Wikipedia anyway, is about
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what our eyes could perceive if they operated like a still camera and just
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took snapshots as we went about our business. But they don't. Instead, when
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we look around, our eyes are adjusting constantly to achieve an estimated
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maximum dynamic range of as much as 20 stops. To put that in perspective, the
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best cinema grade digital cameras top out in the neighborhood of 14 to 16
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stops of dynamic range today. And while that allows their operators to capture
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beautiful images that have a mixture of bright light and deep shadows without
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clipping or losing so much detail that all the camera captures in a given
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region is complete blackness or blown out pure white. It would appear that to
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achieve what the eye can more is basically better and we've still got a
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lot of work to do, right? Enter HDR or high dynamic range imaging. This
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technique attempts to make the image on your phone or camera look more true to
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life by revealing more details in the shadowy areas of an image and in blown
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out bright areas by exposing the image multiple times to compensate for the
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limited dynamic range of your capture equipment. It's not a new technique by
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any means and basically all HDR implementations work in pretty much the
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same way. The camera records an image multiple times in rapid succession at
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varying exposure or brightness levels. Then software techniques are either
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automagically or manually applied to blend them together into one image,
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borrowing the details in the shadows from the brightest image and the details
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in the bright light from the darkest one and putting them all together in an
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attempt to recreate what the eye would see if you were just looking around
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normally at the scene that you're trying to capture. In theory, it's great. And
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there are certainly situations where an experienced VSSLR user with a tripod and
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a very still subject can tastefully use HDR to produce very pleasing images. But
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there are some challenges. Number one is motion. A moving subject will not look
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good with HDR because whether you're capturing three images the way most
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smartphones do or whether you're capturing 20 plus the way a manual DSLR
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user might, someone moving through the shot or even something as subtle as
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leaves blowing in the wind will usually completely ruin the image. Number two is
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scenes with vivid colors or interesting looking contrast. While HDR
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post-processing may bring more color into a dull image, it can have the
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opposite effect in an image where you've already got vibrant color. And of
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course, if you're looking for like artful high or low contrast, by its very
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nature, it will reduce that effect. In fact, the situations where HDR might be
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legitimately useful are pretty few and far between. A backlit skier in the
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shadow of a tree with a beautiful mountaintop brightly lit landscape
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behind her might be better captured with HDR. But this is mostly only true if the
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objective of taking the image is to get a more practical image where you can see
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the details in the skier's face as well as the landscape because often HDR
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counterintuitively ends up looking surreal rather than more natural. But I
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think there's a place for that. While many purists may disagree with the use
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of HDR entirely, this is the kind of argument that I often have with my
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production crew where they might want a super sexy shallow depth of field shot
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on a product and I might just want to close the aperture, boost the gain to
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high hell and produce an image that allows the viewer to look at any part of
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it and get a clear idea of what the heck they're looking at as opposed to
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creating something that is better art or more natural looking. Speaking of better
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art and more naturally looking, what in the heck were those? You may have
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noticed some absolutely stunning examples of HDR landscapes just there.
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All of which were downloaded from shutterstock.com using our account,
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which we love because of how much easier it's made finding graphics and images
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for use in fast as possible. Shutterstock.com has over 35 million
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stock images to choose from. All the way from simple little vector graphics that
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we use to illustrate the points that we're making to shots of models
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depicting emotions that we want to express to beautiful HDR images like the
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ones that you just saw. And the best thing about it is that it's hassle-free.
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You grab images alakart or in a monthly subscription bundle like us and you
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never think about royalties or usage rights again. They've got plans designed
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for small groups like us all the way up to enterprisegrade plans suitable for
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broadcast television. And it's absolutely free to try. Head over to the
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website and use their incredibly powerful search tool to start browsing
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their entire image library and pick the ones you want. Just make sure when it's
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time to check out, you use offer code techquicky 514 so you can save 20% and
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so they'll know who sent you. Thanks Shuttertock for sponsoring today's
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episode. Thanks to you, the viewer, for watching. I'd also love to hear your
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comments on this topic. Please mash those like and share buttons if you
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enjoyed the video and hit that dislike button at least twice for each moment that bored you. It helps us improve.
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Leave a comment on whether you use HDR, what you use it for, and whether you
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believe in the legitimacy of it as a as a piece of, you know, practical photo
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taking or video capture, you know, technique that you keep in your arsenal
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and that all got awkward really fast. Post requests for future techquickie
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