How Was It Done? HDR Trains

It's one of the main methods of inter-country travel in Europe. In the United States, they're diesel burning goliaths that pull freight from state to state. In China, they are beating world records, running from province to province in ever lessening times. They are trains and to a photographer, they are a perfect subject to photograph in HDR.

The following photos were taken at Maastricht Central Station which is a fairly busy train station at the heart of the Limburg region.



So, how was it done? Firstly, this photo is an HDR photo. HDR stands for High Dynamic Range, which essentially increases the amount of dynamic range that can be put in an image. What is dynamic range? Well, it is the range from bright light (highlights) to dark ones (shadows). A camera's sensor has much less range than the human eye (or even film) so a method called local tone mapping is employed to blend the light, dark, and midtones of several photos (each differently exposed) into one photo. This can be done one of two ways, dedicated HDR software, or tone blending with Photoshop (or similar software). I personally use Photomatix software for HDR.

This photo is an HDR composite of three photos, one underexposed by 2 stops, one properly exposed, and one 2 stops overexposed. This can be done with the "bracketing" feature of your camera or by manually changing the exposure of each.

---------------------------------------------------------------

Note: Using this technique in a busy scene may result in some strange artifacts as objects move around in the scene. This can be remedied with a different technique of HDR. This involves taking one RAW photo and creating three new photos from that RAW file, one over, under, and properly exposed. Finally, merge these photos with your software. This may introduce some image noise as you push a properly exposed image too high or low.

---------------------------------------------------------------

So now the image itself. The image was taken with a Pentax *ist DS with the 18-55mm kit lens. This is my primary setup as it is lightweight and the focal length range is flexible. I shot in Aperture Priority (Av, or A) so I could control the aperture and let the camera do the rest. The base exposure (the middle exposure) was at f/4, 1/10 sec., ISO-400, at 28mm. The camera bracketing took care of the 2 stop under/overexposure.

The HDR was created by merging the three photos in Photomatix and lastly the resulting HDR TIFF file was edited in Adobe Photoshop Lightroom. HDR is a very subjective style of photography. Since there are so many different settings, the best way to get a good HDR is to experiment with all the different sliders and settings until you arrive at a photo you like!

There's a catch. HDR works best with RAW files. RAW files inherently have more data than JPEGs (which have been compressed). The above shot was made with three JPEGs. Below is a shot made with three RAW files:



Notice the difference? Photomatix was able to extract more detail from the RAW files and hence you get a richer, more detailed HDR with less noise artifacts. Look at the photo of the NS VIRM (the yellow train), see that weird spot on the window? That's a compression artifact from developing an HDR photo from JPEGs. Of course this is not a fair test (different subjects/conditions/etc.) but believe me, if you're not shooting RAW yet, you're missing out on the capabilities of your camera.

In terms of composition, what do you see? Yup, with images like these, I like to use wide-angle lenses and strange angles. Of course this is subject dependent, but with trains, I want to create this image of raw power and using extreme angles gives you a bold, powerful result. Just look at portraits of CEOs, low angles are almost always key to demonstrate authority. Below is an example of using a telephoto lens (which tends to compress a photo) and a standing position:



Because the train is decommissioned, I chose to use a "weaker" angle. Additionally, this is the type of subjects I like to photograph in HDR. HDR tends to bring out the dirt and grime (details!) in a subject and this shot is a perfect example. This is why HDR is suited to buildings, vehicles, etc. and not [usually] for portraits, animals, etc.

So the images above are what came out as the final results! If you need any help understanding some of the terms here, would like to comment or suggest new features, or add your own personal thoughts, comment or contact me!

---------------------------------------------------------------
If you like this, please share with your fellow photographers! Not only will this information be spread out to help more photographers, user feedback will improve the content posted to the website!

Also check out:
My DeviantArt Page
My Flickr Page
My Facebook Page