7 Steps of High Dynamic Range (HDR) Photography

by Steve Rich

HDR photography combines details from 3 or more separate exposures of the same subject.

·        One exposure is “normal” (0 compensation) to capture details in the mid tones.

·        One exposure is “underexposed” (for example, -2 f stops compensation) to capture details in the highlight areas.

·        One exposure is “overexposed” (for example, +2 f stops compensation) to capture details in the shadow areas.

HDR software combines details from all three exposures. That’s where the magic happens.

 

Here's a normally-exposed image of the Old Mill in Pigeon Forge, Tennessee. It' OK, but notice that the sky is completely "blown out" - so over exposed that no detail is visible.

 

This photo is underexposed by 2 full f-stops. There is detail in the sky and in a couple of highlights, but nowhere else.

 

Now here's another shot that is over exposed by two full f-stops. Plenty of detail in the shadows but even the mid-tones are too light or totally blown out.

Here Steve has taken the highlights from the underexposed image - the midtones from the normal - and the shadows from the overexposed image and combined them.

 

Step 1 – Pick your shot

HDR allows you to see into the shadows. To do this you need a subject that typically has a good amount of contrast between light and dark. HDR draws out the details that you would normally not pick up on with the naked eye. So it is also good to have a subject that does have small details like wood, stone, antiques, and/or clouds to name a few.

Step 2 Tripod and Camera setup

If you desire sharp and clear images with HDR, you NEED a tripod or something stable to have your camera mounted on. Ghosting can occur when a camera shakes or movement occurs. Final images are blurred.

Camera setup: Some cameras (not all) offer a setting called Auto Exposure Bracketing (AEB). Read your manual to see if your camera has this feature.

In AEB mode the camera takes 3 or more photos in a row; one normal, one at -2, one at +2 (you can change the amount of compensation and maybe the number of exposures taken). These photos will be taken quickly and you might be able to manage holding the camera by hand. If not, you can make the multiple exposures manually; the tripod would REALLY be required.

I use these settings on my Canon DSLR

·   AV mode/Aperture Priority

·   AEB -2/0/+2, and set the aperture to f11.

·   I set the self-timer to 2 seconds to minimize shake  

·   A shutter trigger release is also a good option instead of the timer.

Step 3 Check the Scene

Check the ENTIRE scene carefully. Initially, you might think you have a great shot. But, be sure to look all around the entire scene before you take your shot(s). Watch out for the neighbors’ bright blue kiddy pool behind that old barn. The last thing you want is a great subject but the surroundings or background detracts from your focal point.

Step 4 Take the shots

Once you are pleased with your subject and surroundings... Take the shot(s)! I typically shoot 3 exposures (-2/0/+2) outside. Inside I will shoot sometimes 6 shots. Windows need more images taken because the difference in brightness from the interior is so great.

Step 5 Load the images to the computer

Load your photos onto your computer - specifically, the multiple exposure AKA "bracketed" images onto your computer. Raw images take up more room on your computer.

Step 6 Bring images into Photomatix Pro or an equivalent HDR program.

Select the multiple exposure images you just loaded on your computer and now load them into

Either "Browse" for your images, or "Drag & Drop" the images into the window. I select all of my images and then "drag & drop" to the Photomatix Icon on my desktop. This opens/activates Photomatix with my images already selected. Once your images are selected, click OK. 

Step 7 - Tone Mapping Details Enhancer Settings

General Settings

 

•           Strength: Affects the degree to which contrast and detail are enhanced in the image. A value of 100 gives the maximum amount of enhancement. To get a more natural effect, move the slider to the left. The default value is 70.

 

•           Color Saturation: Controls the saturation of the RGB color channels. The greater the saturation, the more intense the color. Move the slider right or left to change the setting value of 0 produces a grayscale image. The value affects each

color channel equally. The default value is 46.

 

•           Luminosity: Controls the compression of the tonal range, which has the effect of adjusting the global luminosity level. Move the slider to the right to boost shadow details and brighten the image. Move it to the left to give a more “natural” look to the resulting image. The default value is 0.

 

•           Detail Contrast: Controls the amount of contrast applied to detail in the image. Move the slider to the right to increase the contrast of the details and give a sharper look to the image. Note that increasing the contrast also has a darkening effect. Move the slider to the left to decrease the contrast of details and

brighten the image.

 

•           Lighting Adjustments: Affects the overall 'look', controlling the extent to which the image looks natural or surreal. When the Lighting Effects Mode box is unchecked, move the slider to the right to make the image look more natural and to the left to make it look more 'painterly' or 'surreal'.

 

•           Lighting Effects Mode: The checkbox lets you switch between two modes for the Lighting Adjustments setting, where each mode produces slightly different results. Checking the box tends to produce results with a type of Magic Light' effect. Note that finer control is not possible in Lighting Effects mode.

 

•           Smooth Highlights: Reduces the contrast enhancements in the highlights. The value of the slider sets how much of the highlights range is affected. This control is useful for preventing white highlights from turning grey or uniform light blue skies becoming dark blue-grey. It is also useful for reducing halos around objects

placed against bright backgrounds. The default value is 0.

 

•           White Point – Black Point: These sliders control how the minimum and maximum values of the tone mapped image are set. Moving the sliders to the right increases global contrast. Moving them to the left reduces clipping at the extremes. The White Point slider sets the value for the maximum of the tone mapped. The Black Point slider sets the value for the minimum of the tone mapped image.

 

•           Saturation Shadows: Adjusts the color saturation of the shadows relative to the color saturation set with the Color Saturation slider. Values higher than zero increase the color saturation in the shadows. Values lower than zero decrease it. The default value is 0.

 

•           Shadows Smoothness: Reduces the contrast enhancements in the shadows. The value of the slider sets how much of the shadows range is affected. The default value is 0.

 

•           Shadows Clipping: The value of the slider sets how much of the shadows range is clipped. This control may be useful to cut out noise in the dark area of a photo taken in a low-light situation. The default value is 0.

 

•           360º image: Checking this option eliminates the seam between the left and right sides of a panorama viewed in a 360º panoramic viewer. The seam would otherwise show because Details Enhancer takes into account local contrast, assigning different tonal values to the right and left parts of the image. The default value is unchecked. Note that this option is not enabled when the image is in portrait mode, as the option is intended for panoramas. The default value is 0.25% for the White Point setting and 0% for the Black Point setting.

 

•           Gamma: Adjusts the mid-tone of the tone mapped image, brightening or darkening the image globally. The default value is 1.0.

 

           Temperature: Adjusts the color temperature of the tone mapped image relative to the temperature of the HDR source image. Move the slider to the right to give a warmer, more yellow-orange colored look. Move the slider to the left for a colder, more bluish look. A value of 0 (default) preserves the original color temperature of the HDR source image.

 

Advanced Options

 

•           Micro-smoothing: Smoothens local detail enhancements. This has the effect of reducing noise in the sky, for instance, and tends to give a “cleaner” look to the resulting image. The default value is 2. Important note: The Loupe may not properly show the effect of the Micro-smoothing setting when the area magnified is uniform. If you want to see the effect of the Micro-smoothing setting at 100% resolution on a uniform area such as the sky, you will have to select an area that contains an object in the scene in addition to the sky

 

•           Saturation Highlights: Adjusts the color saturation of the highlights relative to the color saturation that was set with the Color Saturation slider. Values higher than 0 increase the color saturation in the highlights.  Values lower than 0 decrease it. The default value is 0.

 

Resources: Steve has posted links to the software we have demonstrated most – and use the most – on his site: http://steverichcollectible.blogspot.com

Photomax is “standalone”. If you order be sure to use the coupon code for a 15% discount on Photomatix Pro Aiken HDR