HDRI H igh D ynamic R ange I magery (or just HDR)

1. HDRI High Dynamic Range Imagery (or just HDR) • When this presentation is over, I hope to have answered • two questions about HDR: • So I know what it stands for, but what the heck is HDR? • The technical definition • HDR plain talk • How can I make an HDR image? • The nuts and bolts basics

2. WHAT THE HECK IS HDR? The Technical Definition HDR is a set of techniques that allows a greater dynamic range of luminance between light and dark areas of a scene than normal digital imaging techniques. The intention of HDR is to accurately represent the wide range of intensity levels found in real scenes ranging from direct sunlight to shadows. The process is commonly used in real estate and architectural photography markets due to its advantage of simultaneously and evenly exposing high and low lit areas within a room. HDR has now gone beyond the quest to equally and perfectly expose a photograph, to a realm of exaggeration that satisfies the artist within. As a result, many photographers around the world have adopted this medium as a new form of “photographic art”.

3. WHAT THE HECK IS HDR? Plain Talk about HDR I like to say that HDR is a composite of three or more photos of varied exposure sandwiched together to make an evenly exposed photo Think of the illustration to the left as a spectrum of light that you might find in a room that is naturally lit from sunlight entering through a window. Depending on the end result you’re after, this could be a situation in which you’d want an evenly exposed picture. Because of the wide range of dark & light areas within the frame, this could prove to be a tough task without a flash. In a case such as this, some photographers use the HDR process to reach an evenly exposed end result. With HDR you would take at least 3 pictures at different exposures, one evenly exposed, one over exposed, and one under exposed. Then you take all 3 (or more) images and process them in a program to get your desired HDR affect. More to come on this in a minute. I like to use HDR for the dramatic and surreal affect it often produces rather than using it as a tool to achieve natural looking results. Others prefer to tone down the exaggerated look and maintain a more realistic picture.

4. HOW CAN I MAKE AN HDR IMAGE? • The Nuts & Bolts Basics • Essentials: • Camera with manual settings and bracketing capability • Tripod • Cable release • A computer program for creating your HDR image, such as Photomatix Pro Taking HDR pictures: • Find some place that provides a wide spectrum of light and dark. • Good subjects are those which remain completely still. Rooms and buildings are good examples. HDR images of plant life or nature are difficult because of movement caused by the wind - but not impossible. I have read, and discovered myself that generally speaking, people are usually not the best subjects for HDR. These are only general guidelines, keeping in mind that I consider this an art form - so anything goes if YOU like it.

5. HOW CAN I MAKE AN HDR IMAGE? • The Nuts & Bolts Basics • Taking your HDR pictures / continued: • Set your camera up as you would any other time, but with these exceptions: • Use automatic exposure bracketing if your camera has this option • Here you make the choice of whether or not you want to use 3 or more images to process later on in your HDR program. I usually use 5 since it provides some more flexibility during HDR processing. If you don’t have a bracketing option you’ll just have to manually adjust the exposure settings for each image in the series. • Set camera to aperture priority • To get your three (or more) varying exposures make SURE you adjust shutter speed, NOT aperture. If you have multiple images of the same subject with different aperture settings, the end HDR image will have fuzzy edges. Remember - aperture priority for sharp HDR. • Attach cable release / or use camera timer • It is imperative that you avoid camera shake. The images you take MUST be very Sharp. Prevent this by using your cable release. If you don’t have one, use your timer.

6. - 2 stops - 1 stop + / - + 1 stop + 2 stops HOW CAN I MAKE AN HDR IMAGE? • The Nuts & Bolts Basics • Taking your HDR pictures / continued: • Attach your camera to the tripod, compose your shot and take your 3 or 5 shots. • You now have 3 or 5 images ready to process in your HDR program. I use photomatix pro, which retails online for $99 at www.hdrsoft.com. It is very simple and user friendly. It is also possible to use Photoshop, and other proprietary programs you can find online through a google search of HDR software. You must have a computer program to complete your HDR image. Which program you use - and the settings you use are completely dependent on your personal taste. I rarely use the same setting for any two HDR images.

8. Good Luck Creating Your Very Own HDR Images!