Over the past number of years a tremendous amount has been written about HDR imaging and the state of the art has evolved at a rapid pace. This blog contains some of my thoughts about this topic, some of the work that I have done in HDR and a tip or two.
First off, what is HDR? High Dynamic Range photography is a combination of photographic and editing techniques for extending the dynamic range of luminosity of an image. What this means in real-world terms is that some of the darker parts of a scene can be treated with more light and some of the brighter parts can receive a bit less light, so that the overall effect results in a more complete viewing experience of the scene when processed.
The concept of extending the dynamic range covered in an image is not as new, as you might think: in the 1850s, French photographer Gustave LeGray combined multiple negatives of sea and sky to create seascapes that are stunning to behold with dramatic skies. Significant additional developments were made in the 1930s and 1940s through manual dodging and burning (increasing and decreasing of exposure) of areas in a negative to create a more dramatic print; Ansel Adams was a true artist in this process, as can be seen in many of his famous landscapes.
The advent of massive processing power in desktop computers combined with Digital Photography has created a new level of interest, which has allowed many photographers to capitalize on some of the algorithmic advances that have been made in the 1980s and 1990s in image processing.
At this point in time, there are also numerous cameras available, which do the HDR processing on-the-fly, taking multiple images and combining them into a single HDR image with preset processing settings.
As touched on earlier, the HDR process extends the dynamic range of luminosity in an image; this enables us to bring the range of image capture somewhat closer to that available in the human eye. Camera sensors have gotten better over the past years, so that the range of the camera’s sensor starts to rival that of the human eye, which may lead one to think that the need for HDR is diminishing. This definitely is true from the perspective of being able to ‘see’ as much as the human eye with the camera.
From my point of view, there is no diminished reason to use HDR imaging, as there are several benefits to working with HDR that cannot be achieved easily through other means, such as:
- The setting of very specific moods within the image.
- Creating that dramatic sky, which Gustave LeGray was after
- Surreal, hyper-realism
There definitely are other great reasons for HDR, but these are some of my personal favorites. I have included a couple of samples from my work with HDR in this post to give a bit of flavor.
I mentioned tips in the beginning of this post, so here are a couple from my experience with HDR:
- Bring a tripod! It will make your processing work that much easier later – the Cape Neddick image was shot free-hand with the camera on HDR, so it is possible)
- If possible, meter the light, so that you can set your bracketing up correctly for a good range. As a rule of thumb, I use -2, -1, 0, +1 and +2 for my exposure values in a range of 5 shots; more or less will work, depending on the scene.
- Have a vision of what you want to achieve with your shot, before you process it. Aimless HDR processing is never very fruitful, regardless of the quality of the software; with a vision in mind, you will know when you have arrived at the sweet spot of your endeavor.
- Experiment! Not every image will make a great HDR image, which can only be found out through experimentation.
And, of course, most importantly, have fun when working your images. You’re not going to convince everyone that you did the right thing when processing your ‘killer’ image, but, if you’re happy with the end result, you can smile despite what someone else says about it.