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HDR seems to be one of those amazingly simple procedures that can be turned into an exposure and processing labyrinth. My HDR regimen is about as basic as you can get. I bracket in 1-stop increments (varying only shutter speed), making sure that there is lush shadow detail on one end of the series and marvelously detailed highlights on the other end. For my New Orleans interiors, the number of bracketed shots varied from about 6 to 16. Photoshop CS3 does a terrific job of melding the bracketed files into a 32-bit image. But once that tonally rich 32-bit image is built, I rely on the Tone Mapping plugin (www.hdrsoft.com) to judiciously blend the shadows, midtones and highlights. This software does a much better job than Photoshop alone and is a must-have for anyone wishing to explore the world of HDR photography. Finally, I like to compare HDR to cooking. Even I can read a cookbook and assemble a competent meal. But a real cook knows how to season a dish to bring it to life. HDR work is just like that, part recipe and part art and craft. I use the full gamut of masks and adjustment layers to bring life to tonal regions in the image that might otherwise be flat and unexciting."
So the entire photo can look crisp and detailed, from highlights to midtones to shadows – and photographers needn’t sacrifice any part of their image. And the best way to master this exciting technology is with a thorough an easy-to-follow, and visually spectacular guide. No other title does justice to these cutting-edge techniques, which actually take the viewer into worlds far beyond normal photography –sometimes even beyond normal human perception. Ferrell McCollough, (see bibliography) a widely respected photographer, pushes the boundaries and inspires others to pursue their artistic vision, too. The amazing results simply can’t be achieved any other way.
HDR seems to be one of those amazingly simple procedures that can be turned into an exposure and processing labyrinth. My HDR regimen is about as basic as you can get. I bracket in 1-stop increments (varying only shutter speed), making sure that there is lush shadow detail on one end of the series and marvelously detailed highlights on the other end. For my New Orleans interiors, the number of bracketed shots varied from about 6 to 16. Photoshop CS3 does a terrific job of melding the bracketed files into a 32-bit image. But once that tonally rich 32-bit image is built, I rely on the Tone Mapping plugin (www.hdrsoft.com) to judiciously blend the shadows, midtones and highlights. This software does a much better job than Photoshop alone and is a must-have for anyone wishing to explore the world of HDR photography. Finally, I like to compare HDR to cooking. Even I can read a cookbook and assemble a competent meal. But a real cook knows how to season a dish to bring it to life. HDR work is just like that, part recipe and part art and craft. I use the full gamut of masks and adjustment layers to bring life to tonal regions in the image that might otherwise be flat and unexciting."
Advantages of HDRI
"High dynamic range imaging permits photographers to apply virtual burn-and-doge techniques in their image editing process, leaving as little or as much to automation as they wish. Digital artists using HDRI are able to create virtual worlds that are as compelling as the real world. Since the physics of light can be simulated in their full glory. Using physically based rendering and image-based lighting, HDR photography and virtual scenes and objects may be seamlessly combined.” Christian Bloch. The HDRI Handbook.
HDR Guidelines by Dan Burkholder
1. Use a Solid Tripod and Quick Release Clamp (www.reallyrightstuff.com).
2. Use a Remote Release. Get the better (more expensive) one that has the LCD screen that lets you set long exposure times easily. Carry a spare battery.
3. Turn off Auto focus or set your camera so it only focuses when you push a but- ton on the back.
4. Use Aperture Priority or Manual Expo- sure Mode (see step 6 below too). You want your aperture to stay constant; only your exposure time should vary.
5. Use the lowest optimal ISO on your camera. Note: this doesn’t necessarily mean the absolute lowest ISO. The Canon 5D, for example, has an “extended” range that offers ISO 50. That lower ISO has lower dynamic range than the optimal ISO 100.
6. Shoot your Sequence in 1-stop increments. I’m not saying that larger increments don’t work; I just know that 1- stop bracket increment work very well.
7. Auto-Bracket may give you enough exposures on some cameras. Nikon has better (9 shot) auto-bracketing than the competition.
8. Most cameras can only go to 30-second exposures in Aperture Priority mode. This means that, if the scene is dark enough, you will have to go into Bulb mode for longer exposures.
9. Set your exposure increments (via menu or Custom Function) to 1/2 or Full stops.
10. Start your exposure bracketing sequence with the short, underexposures. This way, if you are interrupted and have to stop shooting, you will have more expo- sures under your belt than if you start on the looooong exposure end.
11. Turn off image stabilization, even if the manufacturer says it’s OK to leave it on.
12. Turn Noise Reduction to ON, not Auto or Off. High ISO Noise Reduction (if present on your camera) has no bearing in your HDR work (see item 5 above).
13. Bring a stopwatch if you don’t have the more expensive remote release and a small flashlight.
14. Be patient. Remember, most cameras require an amount of time for Noise Reduction that’s equal to the exposure itself. That is, if your exposure time is 4-minutes, the camera will take an additional 4-minutes to perform Noise Reduction after the shutter closes.
15. HDR can’t magically fix optical problems like flare and ghosting. Try to setup to avoid having direct sunlight hit the lens.
16. Dust, finger prints and smudges on your lenses will degrade your tonality and make for additional flare and ghost problems. Clean your kens.
17. Make sure your battery is fully charged and bring spares.
18. Remember the adage: “You can never be too thin, too rich or have too many bracketed exposures.” It’s better to go over board with exposures that seem overly light and overly dark than to get home to find that you don’t have enough highlight or shadow detail.
19. Have fun. And remember the words of Gordon MacKenzie: “Orville Wright did not have a pilot’s license.”
For more information on a HRD workshops with Dan Burkholder visit www.danburkholder.com.
HDR Software
We have listed various software that will allow you to generate HDR images and apply tone-mapping. Tone-mapping is the process of reducing the dynamic range so that it fits into a single image. These are the corner stones of the high dynamic range workflow.
1. HDR Shop (Windows) – www.hdrshop.com. For the scientific minded. Version 1 is free, version 2 $400.
2. Picturenaut (Windows) – www.hdrlabs.com/picturenaut. A lightweight free- ware utility.
3. Photosphere (Mac OS X) – www.anyhere.com. Free. For lighting designers and applications in the architectural field it is a good option. Free.
4. Photomatix (Windows, Mac) – www.hdrsoft.com. Very usable for beginners or power users. Free trial version, $99 for the program. Dan's favorite.
5. FDR Tools (Windows, Mac) – www.fdrtools.com. Very similar to Photomatix and mainly targets the photographers community. Free trial version, $53 for the program.
6. Photoshop CS3 Extended edition. (Windows, Mac) – www.adobe.com. All the best HDR features are exclusively in this edition. $999.
Books about HDR
Bloch, Christian. The HDRI Handbook: High Dynamic Range Imaging for Photographers and CG Artists. Santa Barbara: Rocky Nook Inc, 2007.
Hoefflinger, Bernd. High-Dynamic Range HDR Vision: Microelectronics Image Processing. Computer Graphics. Berlin: Springer, 2007.
Debevec, Pual, Sumanta Pattanaik, Erik Reinhard, and Greg Ward. High Dynamic Range Imaging: Acquisition, Display, and Image-Based Lighting (The Morgan Kaufmann Series in Computer Graph- ics). San Francisco: Morgan Kaufmann: Har DVdr edition, 2006.
Freeman, Michael. Mastering HDR Photography. New York: Amphoto Books, 2008.
McCollough, Ferrell. Complete Guide to High Dynamic Range Digital Photography. New York: Lark Books, 2008.
Weston, Chris. Mastering Digital Exposure and HDR Imaging: Understanding the Next-Generation of Digital Camera. East Sussex England: Rotovision, 2008.
HDR websites
1. www.hdrsoft.com – This website has information on what HDR is and also has downloads, examples and support.
2. http://www.cambridgeincolour.com/tu torials/high-dynamic-range.htm – Information and examples on how HDR works.
3. http://www.popphoto.com/to/3038/ how-to-create-high-dynamic-range-im ages.html/ – A step-by-step guide on the most popular HDR programs.
4. http://tutorialblog.org/hdr-tutorials-roundup/ – A blog that has examples and feedback from users of HDR.
5. http://www.vanilladays.com/hdr-guide/ – This site is an HDR tutorial: How to create ‘High Dynamic Range’ images using Photomatix.
6. http://range.wordpress.com/2006/07/15/modern-hdr-photography-a-how-to- or-satuday-morning-relaxation/ – A blog with feed back and information on HDR.
7. www.hdrphotos.wordpress.com – A HDR photo tutorial.
8. http://www.naturescapes.net/072006/rh0706.pdf – An HDR tutorial emphasizing Nature Photography.
9. http://www.cre-aid.nl/2006/06/13/hdr-high-dynamic-range-workshop/ – An HDR Tutorial.
To read an article in The New York Times “Was It Done With a Lens, or a Brush?”
www.nytimes.com/2006/08/03/technology/03basics.html.
Workshops
A Pragmatic Approach To High Dynamic Range (HDR) Photography with Photoshop.
www.chbphoto.com/education/workshops.html#
Capturing More Light – http://workshops.outbackphoto.com/
www.danburkholder.com – HDR Workshops and a discount on HDR software.
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