Tag: histogram

Big Four Bridge

Big Four Bridge
Big Four Bridge

Click on the image to open a window where it will be enlarged.

This is a single frame edited in Aperture 3. The exposure was within the boundaries of the histogram, with no blown highlights or blocked up shadows, which allowed me to process it in Aperture 3 exclusively and retain the ful dynamic range

Louisville Waterfront at Night

One of the difficulties inherent in shooting night scenes is the large dynamic range needed to capture the scene. The artificial light in the image is usually much brighter than the surrounding areas. When this occurs the highlights are blown out which is almost always in the street lights. This image is one such situation. I shot this image using a five shot bracket series from +2 through -2 stops. Even at that range the centers of the lights are blown out in this image.

My studies of my images at night have led me to adopt a wider range of exposures to offset this undesired effect. My current practice is to go as many as five stops underexposed if I encounter scenes that have large ares of manmade lighting such as this one. I watch my histogram very closely and underexpose until I see the right hand side move completely away from the end of the histogram. I have discovered that by doing that I can subdue the blow outs that occur in the lights themselves.

I merged the five exposures in NIK HDR Efex Pro and then used the default setting as my base to tone map it. I then tweaked the sliders until it was where I liked it and finally returned it to Photoshop CS5 to sharpen it using the unsharp mask tool.

Compositionally I framed the shot with the sunset in the right hand third of the frame in order to balance it with the waterfront on the left. The sky counterbalances the architecture and the complimentary colors of the deep blue sky and the orange waterfront create a harmonious whole.

My point in sharing this image is to show you that the conventional practice of using an automatic bracket set to shoot the scene is not always going to give you control of the entire dynamic range. By using the histogram as a tool to analyze the images in your HDR shoots you can take control and prevent blown highlights such as the street lights in this image.