FreeHDR™ is a free Photoshop add-on suite that performs High Dynamic Range (HDR) align and blend on digital photographs. Compatible with both Windows and Mac platforms in 32- and 64-bit processing, it operates in Photoshop CS4 and CS5 (Photoshop Extended required for 32-bits/channel). FreeHDR works with both B&W and Color images in 8-bits, 16-bits and 32-bits.

FreeHDR™, a High Dynamic Range operator, combines images without “grunge” effects. FreeHDR™ finds an optimal alignment for images to be blended (with multiple quality settings) that does not suffer from the flaws in Photoshop’s alignment. The blending of the images occurs with accurate color rendition, reduced noise, no ghosting, and attention to the realistic nature of the photograph itself, rather than an interpretation.

Compare the color rendering, alignment and blending of FreeHDR with Photomatix and other HDR programs. We think you’ll agree that the results are a notch above the rest.

FreeHDR processes 2 to 100 images in Photoshop by aligning them on layers and blending multiple exposures. It is an integral part of PercepTool 2™. PercepTool 2™ is available through the links above.

FreeHDR works with 8-bit, 16-bit and 32-bit images (Photoshop CS4 Extended or CS5 Extended needed for 32-bit operation) with 64-bit processing engines on both Mac and Windows platforms (Mac OS 10.6+, Windows Vista and Windows 7). We suggest working with either 16-bit or 32-bit image files. If you are working with 8-bit jpeg files, convert them to 16-bit TIFF images before working on them to achieve more consistent results (This can be set up when importing into Lightroom, but must be done manually in Photoshop). 8GB of RAM is recommended for 32 bits/Channel processing.

High contrast image manipulation is the largest global technical problem in digital (and traditional) photography. FreeHDR combines 2 or more images and aligns them precisely with a multi-alignment program. Our default beginning stance achieves the best blend of images that produces the most natural look. This is the standard, and we have made great pains to make it the best possible one available.

High Dynamic Range (HDR)

When I began searching for a way to duplicate Ansel Adam’s Zone System for digital photography back in 1996, the problem seemed daunting. Instead of exposing and developing for scene contrast, digital photography defied all means of manipulation. For a scene that had more range than the film could handle (and the paper could hold), we exposed to get full shadow detail and developed the negative in the darkroom for adequate detail in the highlights. Everyone in B&W Large Format (4x5 and up) Fine Art photography did this.

I started experimenting by combining 2 images, one overexposed and one underexposed, on 4x5 B&W sheet film, aligning them manually in Photoshop, and running them through a complicated Layer routine that was published in Tips From The Experts in Photoshop CS1. Soon afterwards I met a friend who had borrowed algorithms from NASA (open source) that could blend two or more images without complicated processing in Photoshop. This first piece of HDR software was call Optipix, and it included many useful plugins for Photoshop along with this HDR capability.

Since Optipix there have been at least 25 HDR software programs and the list is still growing. The popularity of this software began because it solves photography’s greatest technical problem:

CONTRAST

All of these programs do an adequate job of taking many images in a bracketed sequence of exposures and combining them to produce an HDR image - an image that has detail in the shadows and highlights with no clipping. However, image alignment is critical to these procedures. With good alignment at a low noise blend there are more contrast and sharpening tools available.

In addition to blending images together to make a broader dynamic range, software developers have added Tone Mapping software to improve contrast and fine detail in the blended image. We believe that much of this Tone Mapping adjustment has gotten out-of-hand and produces images that are decidedly unrealistic but ones which are passed off as realistic (the word in art is illusionism).

FreeHDR™ is all dedicated to reproducing a perceptual and emotional image that you first saw and felt in your eye and camera. These tools rely on research from the perceptual processing of the human eye and brain, from Lightness science, from research into the great masters of painting, and from the practice of photography. We have left what we call the “grunge” effect to others.

Light,
George