The advent of digital photography has brought revolution after revolution. As I’ve said before, generally, in the days of film what you got in the negative or slide was pretty much what you were stuck with. One problem with photography then and now, but especially in the days of film, is the limited dynamic range, also referred to as exposure latitude. When we view a scene with our amazing eyes, we can see detail in the darkest shadows and the brightest highlights virtually in the same instant. We can discern a dynamic range on the order of 25:1. Our eyes adjust so rapidly that we don’t even notice this amazing ability. In photography, the range we can capture is greatly reduced. With film it was on the order of 9:1, or 9 f stops. When making a print, this range is reduced even farther to somewhere on the order of only 4 f stops. The great photographic master, Ansel Adams, based his entire method on maximizing the dynamic range he could capture on film and in print. He did this by over or under exposing the film in combination with applying specialized developing techniques using various chemical developers and developing times. He would then manipulate his prints by dodging and burning areas and again, in combination with developing techniques and chemicals, to extend the apparent dynamic range of a photograph. These were complicated techniques. All, to create a photograph that matched his imagination and hold detail in the blackest blacks and the whitest whites. This was the holy grail in the hey day of black and white photography.
Enter the world of digital photography. Now, my sensor has a greater latitude than film somewhere on the order of eleven f stops. But still, it doesn’t come close to the capability of the human eye. And you also have the problem of the lesser latitude of photographic paper.HDR to the rescue: high dynamic range photography. Now we can capture three, five, seven or nine, or even 21 different exposures from very dark to extremely bright and merge them all in HDR software. This creates an image that combines all the details of the blackest blacks and whitest whites in a single frame.
So what are the steps to creating an HDR photo?
First, it’s imperative that you use a tripod. I’ve tried to do it hand-held, but shooting a series of bracketed exposures even shooting at five frames a second will inevitably have movement between each frame.
Next, you need your series of bracketed exposures. This means that you have to shoot the high contrast scene you’ve chosen with those three, five or seven different exposure settings ranging from very under-exposed to very over-exposed.
These are the five brackets I used to create the photo at the top of this post:
-2 stops
-1 stop
Normal
+1 Stop
+ 2 Stops
Many cameras have the capability to automatically bracket exposures. This makes things much easier. Without auto-bracketing, you have to manually adjust your exposure between each photo.
Some consumer cameras, especially point and shoot cameras, can now create HDR photos automatically in the camera.
I usually set my camera to do five brackets with a one f stop difference between brackets. This five f stop range from under-exposure, to capture detail in the brightest highlights, to overexposure, to capture the details of the darkest shadows, is usually sufficient.
I said above that you can do even more brackets. You can get crazy with them shooting fifteen brackets at intervals of 1/3 of a stop, but I haven’t found much advantage to that.
You first have to establish you median exposure. You do this by using your histogram as in this blog post:
http://dreamcatcherimaging.blogspot.com/2013/07/understanding-camera-histograms-in.html
After that, set your auto-bracketing and make your exposures. You can use your fingers like in the Panorama post to mark the beginning and end of your brackets:
http://dreamcatcherimaging.blogspot.com/2013/07/panorama-photography-photographing-and.html
But after importing the photos, it’s usually pretty obvious what photos you’ve shot for HDR.
And another thing, I always shoot my exposures from under-exposed to over-exposed, from - to +. With auto-bracketing, it’s a setting on the camera. It makes it easier and more obvious which photos I will use to create the high dynamic range photograph.
Once you’ve imported the photos, you need an HDR program to process them. Photoshop has HDR capability, but I prefer either Photomatix or Nik’s HDR Efex Pro. Photomatix and HDR Efex are plugins for programs like Lightroom and Aperture as well as Photoshop and the latest versions of Photoshop Elements. You can export from these program directly into the plugin.
I won’t get into the process of working with the software here, I just want to introduce you to the basic steps. Suffice it to say, there are a lot of things you can do while manipulating your images in the HDR software. Both Photomatix and HDR Efex have presets, kind of like recipes. By clicking on each preset, you’ll get very different looks. These can be fine-tuned with the controls in the software. And as always, just play and have fun. You can’t screw up.
As I said in the title, you’ll be amazed with what you can create. But...there is a treacherous side as well. It’s very easy to become enamored with the saturation, detail and bizarre looks you can achieve with HDR photography.
The internet is full of clumsy, why-to-obvious, and ridiculously over-saturated HDR photos. The challenge is to use HDR subtlety and to create photographs that mirror the reality or convey the feelings you had when you were inspired to photograph the scene in the first place.
I shot the exposures for this HDR photograph during a Vail Nature Center Photography Workshop on Shrine Pass. Clouds frequently present a problem because their brightest highlights get blasted out especially when there are some deeper shadows to deal with. I made five exposures but I only used these three brackets to create the HDR photo.
Here is the final image:
And just to compare the capability of today's cameras and processing software, here is the middle bracket processed in Lightroom 5 only:
You can see that the clouds show much greater texture and the shadow somewhat lower contrast. Which do you like? Well, it's a matter of taste.
Copyright 2013 Dennis Jones/Dreamcatcher Imaging
Check out my travel blogs on my extensive world travels at:
http://www.dreamcatcherimaging.com/blog/
http://www.dreamcatcherimaging.com/blog/
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