HDR Photography: How To Do It And Why
Posted: 11 Mar 2013 06:01 PM PDT
In today’s DSLR photo tip, we will discuss HDR photography, how to do it and why.
For some reason, this has become a real hot button issue with photographers. Some swear by it – others hate it!
First, what is HDR photography?

Defining HDR photography is one of those areas where it can get very detailed and packed with mathematical formulas and whether or not a certain image qualifies and on and on!


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“Inverness Ca. BoatLaunch” captured by Cliff Briggin (Click Image to See More from Cliff Briggin)

For this article, we are just goingto keep it light and explain the basics. Please, all you technical types –don’t bother sending me all the calculus formulas.
HDR stands for High Dynamic Range.
In our past discussions on gettinggreat sunset photos, I alluded to several problems. If you expose for the sky,the ground will generally be under exposed and will go black. If you expose forthe ground, the sky will be over exposed and get washed out.
This is because of the dynamic rangeof the film or digital sensor. It can only record just so much detail. This isgenerally known as the standarddynamic range (SDR). When the details in the scene exceed thestandard dynamic range, they get lost.
Think of a sunset shot with asilhouette of a person. In SDR you lose all the detail in the person and thatis what creates the flat black shape.

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“Business Districtin Nashville” captured by This Room Became A Hill (Click Image to See More FromThis Room Became A Hill)

As I’ve mentioned before, some ofthe detail can be recovered by using split or graduated neutral densityfilters. They would hold back some of the light in the sky, allowing theexposure to be more friendly to the ground. But, there is a better way.
What if we took multiple shots? Wecould take a shot of the sky at its perfect exposure, and another of the groundat its perfect settings – then later in Photoshop or some other program, wecould combine them!
Then we would have a perfectlyexposed sky AND a perfectly exposed ground!
This is a very simple shot – withtwo exposures. Typically, there would be at least three. One of the sky’ssettings, one “normal” exposure, and one with the ground’s ideal exposure.
I’ve seen some HDR photos that go ashigh as 7 bracketed exposures! Bracketing means that you are shooting atexposures both above and below the “correct” exposure. You are bracketing it.
Now, let’s say you’ve done a seriesof 7 exposures, from way over exposed all the way down to way under exposed.When you combine them, you are going to get a dynamic range that is higher thanyour computer monitor is capable of showing.
That is HDR.
It has to do with bits andluminosity and so on… but let’s just say there are several programs that aredesigned to deal with this issue and work their magic with “tone mapping”
That’s a whole ‘nother article.
I think the debate over HDR is thatit isn’t a “pure” image created in the camera. To work in HDR you MUST havesome sort of computer program to combine the images. The HDR haters are thesame ones that used to object to retouching negatives or adding filters, etc.
To my way of thinking, it’s theimage that counts. If you like it, it doesn’t matter what techniques wereemployed to get there.
The whole point to HDR photography,how to do it and why, is that – if well done – the final result can moreaccurately display what you saw with your eyes and give you some prettystunning results.

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“Ghostly Trolley”captured by Tony Lau (Click Image to See More From Tony Lau)

Like everything else, a lot of photographershave gone overboard with the technique and produced some really bad results. Ithink this is what fuels the anti – HDR crowd.
Your assignment for this DSLR phototip, HDR photography, how to do it and why… Is to go online and look up someHDR photographs and see if you like the technique or not! If so, give it a shotand create some simple ones of your own! Then you can look into some of the HDRprograms and become an expert!
About the Author:
Dan Eitreim writes for ontargetphototraining.com. He has been a professionalphotographer in Southern California for over 20 years. He philosophy is thatlearning photography is easy, if you know a few tried and true strategies.






Article from: PictureCorrect Photography Tips
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