Loading Coriolistic Anachronisms

High Dynamic Range (HDR)

[Posted in 2011]

High Dynamic Range Photographs have been at the core of my photographic efforts for the last 4 years. I wrote a tutorial about that long ago when I started playing with the trendy dark art of High Dynamic Range Photography: [[HDR 101 Or how to spend way too much time on a computer]]. Since the world of HDR has been evolving rapidly along with my own vision of things, I will now recap and try and make this post as useful as possible, both in terms of reference and motivation.

If you have ventured here looking for some information about HDR, welcome. I will try and explain the current state of High Dynamic Range Photography and present available alternatives. If you’re already an addict, I hope you’ll get new ideas in here or maybe just find a link or resource you didn’t know about, or even simply leave a comment or suggestion.

HDR imagery was born as a work-around for a very simple but annoying issue: modern digital camera sensors do not have the ability to record a very wide tonal range. To produce a picture file, they squeeze the visible tonal range of a scene into a narrower envelope and doing so, they usually end up blowing the highlights or the shadows – in other words loosing detail in the brightest and/or darkest area of the image. The range between both extremes is just too much for these sensors.

High dynamic range photography is thus a set of techniques that attempt to re-introduce that wider tonal range into an image. In order to do so, the photographer will typically bracket multiple exposures (underexposing and overexposing) and later combine them into a single file containing the best tonal range recorded by each bracketed shot.

There are many ways of achieving this, and more solutions become available every day. As of now, the mainstream software options for quality HDR images are:

Photomatix, a dedicated HDR software solution that has been leading the field for years
Artizen HDR, a powerful newcomer
– Photoshop CS5’s Merge to HDR Pro, a completely redesigned and very competitive tool
Dynamic Photo-HDR by Media Chance
HDR Darkroom
HDR Expose by Unified Color
– My own favorite, FFDD6 by Tim Farrar, a set of Photoshop actions and scripts whose development has sadly been abandoned

And then the free guys:

HDR Luminance

Here is a great review of most of the software above by Captain Kimo, and below is a quick experiment based on the same 3 digital negatives of a bracketed exposure at -2ev, 0ev and +2ev.

Even though the above tools all label themselves as HDR, they work differently and yield different results, so one needs to assess goals, technique and final look desired before choosing which software to use. There are pros and cons for each. Photomatix, for instance, has always been targeted towards the surrealistic look, while Photoshop seemed to aim for a more photo-realistic result. Even with all the new players above, FFDD still represents, in my opinion, the ultimate in photo-realistic HDR, in addition to its magnificent noise reduction. However, the script seems buggy in versions of Photoshop beyond CS4 and that might become an issue for CS5 owners.

Photomatix has just released a beta of the upcoming version 4 which promises great performance, many improvements, and seems to bridge the gap between extreme surreal images and a more conventional look. It is very affordable and well documented. Second best.

CS5 is, well, Adobe. Not for every budget. And while Photomatix might have calmed the surreal approach down, CS5’s new Merge to HDR Pro introduces presets for absolute surreal looks in an obvious effort to compete with its rivals.

Do some research. There are many more alternatives, and manually blending layers remains a possibility to achieve HDR-similar results. In the field, the basics haven’t changed: do your homework, then get it right in-camera and make your post-processing life easy. Always use a tripod, the sturdier the better. Use mirror lock if shooting with a DSLR to further reduce the chance of camera shake, or use the Live Mode which effectively locks the mirror up for the duration of your shoot. Set your camera to an all-manual mode to keep your aperture, focus, white balance and other parameters constant. Take at least 3 bracketed shots at 2 stop intervals, 5 is better. Expose your brackets slightly “to the right” in order to acquire as much detail in the highlights as possible.

Then go home and play. All the tools above require some form of post-processing once the HDR image has been computed. It is called Tone Mapping in most programs, but FFDD simply needs conventional RAW development to be applied to the high dynamic range negative generated. Either way, this is where your creativity is unleashed. It’s where you can make it happen or blow it.

Some people, like Trey Ratcliff of Stuck in Customs have made a name for themselves by producing incredibly textured surrealistic pictures. Others, like me, use HDR to recover some tonal range in landscape photography but while conserving a natural look and feel. And then there’s everything in between. HDR does a masterful job at extracting and highlighting textures in mid-tones. It produces marvelous detail in architecture and textured materials but can easily turn human skin cartoon-like. My personal favorite use of HDR is in sunsets and sunrises where it replaces a graduated neutral density filter and allows me to record a scene as my eye saw it, with sky nuances intact but still showing minute details and tones in the much darker foreground.

HDR is fun. It is time-consuming. It remains controversial. It has definitely taken a front-row stance and is being seriously studied by camera manufacturers. The first cameras to offer integrated HDR modes have actually just appeared on the market. They will improve and this will likely become an standard feature on all bodies.

In the meantime, I will keep bracketing furiously and long for the sigh that unavoidably escapes me when I see my high dynamic range photographs finally rendered.

If you need more reading materials, a good starting point would be to browse my previous high dynamic range entries. If you feel this is all too serious or time consuming, simply read [[HDR photography meets quantum physics]] and [[Discussing HDR photography]] for a smile and to defuse the HDR topic a bit. We always tend to take ourselves too seriously when we stumble upon something that triggers our passion and efforts. I wrote those to compensate for that fact. I hope I succeeded.

Speaking of stumbling, if you think this post or others are worth it, kindly use the icons at the bottom to Stumble it on Stumble Upon or any other social network you might be fond of, it will be much appreciated! Have fun and see you in the field!