HDR Imaging - 5 Common Creation Techniques
Photo by Trey Ratcliff
Nowadays, High Dynamic Range (HDR) photography has gained immense popularity among photographers. It ain't Rocket Science, but just a technique to capture high dynamic range image by a single click on digital or film camera. The HDR images are 'in demand' as they give a very surreal and distinct look to the image, which is difficult to capture by simple click of the camera shutter. Photographers rely on softwares like Photomatix, which displays the minutest of details viz. light, shadow etc. and gives satisfying color tones to the image.
Let's explore the 5 Most Common techniques to create HDR Images:
1. Darkroom Technique
The darkroom technique is a method to create single images from two or more separately exposed negatives. This helps in producing an image with right exposure of bright sky and dark foreground. Later, Ansel Adams and friends came up with Zone System, which was not exactly HDR but it improved levels of HDR Imaging from negatives to the prints. They are the one who discovered the technique identifying right exposure and color tones for printing.
2. Graduated Filters
It's the most easy and least time consuming way to create HDR image. Graduated filter is an optional setting given in the cameras. It is a scale of darker shades to lighter white, usually with darker gray color to whiter tones and even color shift if desired. What it does is, the darker shade is placed on the brighter shades, the horizon of the image should have mid-tones and brighter tones should be placed by the darker shades. The shades are transition of darker tones to lighter. So the brighter sky should have darker portion placed on it and darker portion of the image should have lighter tones.
The camera adjusts to shutter speed and let through the light on the darker scale, aligning to the horizon to the foreground of the image. So darker portion of the filter holds back the light and brighter portion of the filter lets the light through. The only flaw to this setting is it cannot capture light and shadow perfectly with building and mountains above horizon. As the horizon of the graduated filter has the transition of darker shades, so the building or any object above the horizon of the picture doesn't get enough light, which results in cutting the object in two different color tones.
3. Careful Processing of a RAW image file
Most of the current digital SLRs, now have the option of capturing images both in RAW files as well as in JPEG format. It is the easiest and simplest way to convert a RAW file into HDR image with just a single exposure. It is not technically a HDR technique but using the single exposure in RAW format makes it easy to process into the software like Adobe Lightroom or Photoshop. Through these softwares, easily light and shadow details are achieved with more dynamic range which camera seemed to unable to capture.
4. Software assisted, Manual blending of Double Processed Single RAW image file
As it is difficult and risky to capture one RAW format image and convert it into dynamic range, clicking two same images with different exposure brings the desired output. After capturing two images with different exposure, one should process it through the software like photoshop and merge or blend the two images together. It does take lots of pain and skill to blend the two images with exposure, but the result will be satisfying.
5. Manually Blending Multiple Bracketed Exposures
This technique is as same as the double processed RAW file blending technique, but the only difference is here more than two images are captured with different exposures, as required. In this technique, one clicks the photos according to the darker to lighter tones in the image. Again, the blending technique is used to get the high dynamic range image. The whole process is done manually, so it is hectic and painful, but the results in getting perfect HDR image is absolute. The image is clean and sharp which can be used for large printouts and on computer screen.