High Dynamic Range Imagery and your Photography (Part 2) - Temecula, CA

Well in part 1, we defined what a HDR is along with AEB and EV. You have to love these acronyms. If you don’t what these acronyms mean read part 1 of this article.

For taking AEB images for HDR processing I strongly recommend a good tripod. Understand any movement during the AEB process will severely affect your final result. I normally use a 2 second delay to make sure there is no movement on my part. You see, part of the processing of a HDR image in the HDR creation software is the alignment process. If there was too much movement in your shoot it won’t be able to align the images correctly resulting in a misaligned image and unusable. Now again be careful when shooting AEB images in an area that has a lot of movement as your photo will not align correctly. The faster your camera can do continuous shots the better.

So now you have all these photos in threes. Yes they will look strange as one is too dark, one way too light and one is okay. Well that’s what you need to create an HDR image. Now we’re going to discuss how to process these type images, pitfalls and results.



Let’s take these three AEB images and make it a HDR. Several software programs are available out there that can accomplish this task. There are also a couple of free programs available. But beware they will only process a HDR image. Well I can hear you say, “Well that’s what I want to do”, am I right? Simply, try to open a raw HDR image . . . .not! You see your HDR image must be converted. So if you see a free HDR generator software make sure it will tone map and be able to save it as a 8bit jpeg. Adobe CS4 has HDR generating capabilities but it is somewhat cumbersome to use and I don’t care for the result. Personally, I use “Photomatrix” this is an outstanding HDR generation software. User friendly with many tone mapping options where you can make it have minor or major changes. It also has a batch process which is great for processing many pictures in groups of three. I normally come back with 300 pictures and process these AEB images in the batch process and auto set the tone mapping process. The batch process will save you a lot of time when doing many AEB images at once. Tone mapping is required in the conversion process and a simple “save image as” gets you to your end result. But you are not done yet, maybe you are but if you are like me into Photoshop it goes for the removal of any unwanted items within the final image. Also I will run it through “levels” one more time to give it the final desired look I’m looking for.



One more note of caution these files are very large and depending what you are doing with them you must keep that in mind. If you are using them in a web page you will want to reduce the image size and dpi to 72. If you don’t do that the image will take forever to load on your page. However, if you are making prints they are okay as is and just size them to the printed format size you are printing too. Don’t reduce the dpi in this case.



HDR imagery will give you a competitive edge against your competitors and you can charge more for HDR than for normal pictures. I can guarantee you this; your customers will want HDR images and purchase HDR prints over standard prints.

High Dynamic Range Imagery and your Photography (Part 1) Temecula, CA

This 2 part article will address High Dynamic Range Imagery known as “HDR” and what one can do with it for fun and profit.

First I think one should understand what HDR is and the best definition I could come up with and was found on “Wikipedia”.

In image processing, computer graphics, and photography, high dynamic range imaging (HDRI or just HDR) is a set of techniques that allow a greater dynamic range of luminance’s between the lightest and darkest areas of an image than standard digital imaging techniques or photographic methods. This wider dynamic range allows HDR images to more accurately represent the wide range of intensity levels found in real scenes, ranging from direct sunlight to faint starlight. The two main sources of HDR imagery are computer renderings and merging of multiple photographs, which in turn are known as low dynamic range (also called standard dynamic range) photographs. Tone mapping techniques, which reduce overall contrast to facilitate display of HDR images on devices with lower dynamic range, can be applied to produce images with preserved or exaggerated local contrast for artistic effect. (Ref Wikipedia)

The above picture was processed as a non-HDR image. As with the same picture on the right is a processed HDR image.

So how is this accomplished in photography and can you do it? Well it depends on the camera you own. No you don’t need a $4,000 camera to do HDR. Some point and shoot cameras and DSLR’s have this feature. But before I get into what cameras do this let me explain how it’s done.

Basically it is a combination of three (3) successive photographs taken at the same subject with different exposure settings. One dark one regular and one overexposed. Depending on the camera you own you can vary these settings to your own liking. Personally I like 2 down and 2 over the automatic exposure setting.

This is known as Automatic Exposure Bracketing (AEB). Many digital cameras include an Auto Exposure Bracketing (AEB) option. When AEB is selected, the camera automatically takes three or more shots with different exposure settings for each frame. Auto Exposure Bracketing is a very useful option for taking HDR scenes. Understand, AEB was not really intended for HDR photography, but rather for ensuring that at least one of the pictures would be as close to perfectly exposed as possible. This is probably why some camera models only make it possible to auto bracket three shots at a maximum of one Exposure Value (EV) step difference or even less. Note, three shots spaced by one EV are often not sufficient for properly taking HDR scenes. This is why it is important to look at the settings of the Auto Exposure Bracketing features of a camera model to determine whether that camera will be convenient for HDR shooting.

The number of frames per second that the camera can take (referred to as "burst rate") is another important factor for HDR shooting The faster the auto-bracketed shots, the less pronounced ghosting and mis-registration problems will be.

Does your camera have the AEB feature and to what EV? Those are 2 very important questions one should research before buying a new camera when you want to be able to take dramatic HDR pictures. In part 2 of this article we will discuss what settings you want to set your AEB (within your cameras limitations) and how to process those images to your desired effect. Now understand HDR imagery can be taken to the ridiculous side, so how and where you apply it is only restricted by your imagination.