Quick Answers To The 5 Most Asked HDR Exposure Questions

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How many shots do you need to make an HDR merge?
The most common answer is three.
The real answer is … it depends. First, it depends on the contrast ratio of the scene. Second, it depends on the exposure value (EV) increments you use between exposures. Third, it depends on the camera you use.
Many scenes only need 2 exposures. Most scenes need 3. Some scenes need 5. Only a few scenes need 7 or more.

How far apart in EV (exposure value) should separate exposures be?
1.5 stops. (Really any value between 1 and 2 stops.) While you won’t get better image quality if you use more shots separated by less exposure value (less than 1 stop), you also won’t compromise it. While you can also use higher increments (more than 2 stops) be careful – you may produce banding in smooth areas, particularly those with gradations.

Do you need to make HDR merges more frequently with some cameras and less with others?
Yes. Cameras that have a greater dynamic range can capture a higher contrast ratio and so don’t require HDR bracketing as frequently. While this can make a difference for images that would require two and occasionally three shots, for scenes with more extreme contrast ratios HDR merges will be necessary for all cameras.


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XDR – HDR Merges Are A 4 Step Process

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Today’s cameras (including smart phones) can create great looking HDR images on the fly, but to get optimum results it’s best to do this manually. In camera solutions render artifacted JPEGs and give you little or no control over how the results look. For optimum results, make separate Raw exposures and render them manually. While the technology at work is wizardry, this four step process is easy to practice. It’s an essential skill for all photographers.

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1       Expose
Today’s fast burst auto-bracketing cameras combined with software alignment make handheld HDR possible. However, it’s recommended that whenever practical you use a tripod to eliminate any alignment issues between frames that might arise; it’s necessary if exposures are long.
HDR merges require multiple bracketed exposures. The goal is to produce at least one exposure with great highlight detail and another with great shadow detail. You may need additional exposures in between your lightest and darkest exposures to help smooth tonal transitions between shadows and highlights. The most common number of images used is three because this is the default number for auto-bracketing on DSLRs. However, there is no ideal number of exposures for all scenes. Some scenes need as few as two, while others need as many as eight. In general, it’s best to have more than you need, not less. The wider the dynamic range of the scene the more exposures you’ll need. Make sure that separate exposures are between 1 and 2 EV (exposure value)(equivalent to one f-stop) apart. It’s typically recommended that you fix f-stop and change shutter speed to avoid depth of field issues, but other changes in EV will work.

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Merge in Lightroom

2       Merge
After producing multiple bracketed exposures, the next step is to combine them with software into a single 32-bit file.
Simply select the exposures you wish to include (You don’t have to use them all.) and use the software of your choice. The software you use to merge exposures will compensate for alignment and ghosting, from motion of either camera or subject. (Lightroom and Photoshop do excellent jobs.)
Rather than rushing to render this file at the same time, save it – you may want to render it multiple times.


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Capture & Calibrate For The Cure !

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“X-Rite is very excited to announce a limited edition “Pink” promotion!
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Limited Time Offer Supporting the Cure
During Breast Cancer Awareness Month, we’re supporting the Breast Cancer ResearchFoundation (BCRF), the highest rated breast cancer organization in the U.S. We’ve developed two limited edition products with 20% of sales donated to theBCRF!
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Capture for the Cure Limited Edition ColorChecker Passport Photo
For more than 40 years, ColorChecker Targets have delivered accurate and repeatable color results in photography and filmmaking with targets right for every shoot. This handsome and convenient ColorChecker Passport has a custom image with The Cure’s pink ribbon imprinted on the case and a pink lanyard.
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Calibrate for the Cure Limited Edition ColorMunki Display
You know ColorMunki Display as advanced display calibration made simple. This handsome ColorMunki features side panels in the signature pink that is recognized around the globe as a symbol of efforts to find the Cure to breast cancer. 
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Each of these products is limited to 2000 pieces.
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20% of the proceeds go to the BCRF.
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9 Great Quotes On Being In Sync

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Enjoy this collection of quotes on being in sync.
“Tidal rhythms have an effect on our physiology…. When we feel out of sorts, our body is out of sync with the body of the Universe. Spending time near the ocean, or anywhere in nature, can help us to synchronize our rhythms with nature’s rhythms.” –
Deepak Chopra
“Sometimes you are in sync with the times, sometimes you are in advance, sometimes you are late.” – Bernardo Bertolucci
“Be out of sync with your times for just one day, and you will see how much eternity you contain within you.” – Rainer Maria Rilke
“When mind and action are separate, zen is lost. We keep the two in sync by paying attention.” – Philip Toshio Sudo
“There’s something about the rhythm of walking, how, after about an hour and a half, the mind and body can’t help getting in sync.” – Bjork
“Part of the joy of looking at art is getting in sync in some ways with the decision-making process that the artist used and the record that’s embedded in the work.” – Chuck Close
“It happens so quickly it seems like it’s coming from somewhere else. It’s not It just means that you’re in sync with yourself. And whatever your goal is, in terms of hearing a melody or a lyric, the closer you get to it, the faster it comes out and the easier it is to “spit it out”, as it were.” – Harry Nilsson
“Dream big, as long as you do it in sync with your truth, with your heart, your brain. And you are not hurting anybody, go ahead and do it.” – Angelique Kidjo
“I feel that all you can do is give it your absolute best with whatever gifts the universe has given you. And if you make it in some way that other people can recognize, that’s fine. But even if you don’t quote-unquote make it, you’re fine, if you’ve given it your whole heart and soul. You’re totally in sync with your purpose and with the universe. And that’s fine.” – Alice Walker
Explore The Essential Collection Of Creativity Quotes here.
Discover more quotes in my social networks.
View The Essential Collection Of Creativity Videos here.

What Is Exposure Value ?

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In photography, exposure value (EV0 is a number that represents a quantity of light. Each increase or decrease in number indicates a doubling or halving in the amount of light; often referred to a stop of light.


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What In The World Is HDR ?

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1 EV is equivalent to 1 F-Stop of brightness

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These Contrast Ration (CR) figures are approximate

Dynamic Range
Today, many people think HDR refers to the practice of merging bracketed exposures with software, but HDR actually applies to everything in an imaging workflow - capture, processing, display, and printing.

What is HDR? HDR is an acronym that stands for High Dynamic Range. It’s the opposite of LDR or Low Dynamic Range Imaging.

What is dynamic range? In imaging, dynamic range (DR) is the highest overall level of contrast found in an image. In other fields, such as in the audio industry, dynamic range is used to describe similar phenomena. In audio, DR is defined as the logarithmic ratio between the largest readable signal and background noise. DR is akin to signal-to-noise ratio. In imaging, DR refers to the entire image. Consider an image a signal – and every signal has some noise.

The values used to specify dynamic range can be charted on multiple scales. Whatever language is used to describe this phenomenon, two critical factors must be addressed; the total range of brightness and the fineness of the steps used within the scale.

Two scales are most useful for images – exposure value and contrast ratio. Exposure value (EV) is easier to use while contrast ratios better display logarithmic increases in light intensities. Both refer to the same phenomenon – relative increase or decrease in brightness.

The EV scale makes it easy to compare the ratios rather than the big numbers of logarithmic progressions; each successive EV rating represents a doubling of values. The exposure value (EV) scale has been used by photographers for ages. The International Organization for Standards (ISO) defines EV 0 at an aperture size of 1 and a 1 second exposure time. The same EV can be achieved with any other combination of f-stop and shutter speed that produces the same amount of light.

‘The contrast ratio scale specifically delineates values; when you use this rating you instantly see how much greater each step in a progression is than the previous one because the numbers are so much bigger. You can convert EV to contrast ration or vice versa with the right formulas. 2 (power of EV) = contrast ratio (2*8=256 for a contrast ratio of 256:1) or EV=log10(contrast ratio)*3.32 (log10(4000)*3.32=12EV

Dynamic range, gamut, and bit-depth are often confused. Though related, they’re all different. Dynamic range refers to a total range of luminosity values. Gamut refers to a total color capacity, including saturation. Bit depth refers to the number of points of data between values or the fineness of the increments in the scale. Just because an image is wide gamut doesn’t mean it is HDR or has high bit depth, but it will contain more and potentially better data if it does. Just because an image is HDR doesn’t mean it is wide gamut and has high bit depth, but it will contain more and potentially better data if it does. You can’t convert low dynamic range, small gamut, low bit depth information to high bit depth, wide gamut, high dynamic range information. To get it and use it, you have to capture high-quality information upon exposure and preserve it throughout your workflow.


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