AAUG Reviews

by Guy Okada, AAUG Member

Creaceed is a team of “passionate people” who live in Belgium and they’ve produced a line up of six unique products in the imaging niche. They also have a product, Voice Commander, that dfines keyboard commands which are activated by voice. At Macworld this past year I recall seeing Creaceed’s booth and was intrigued by their product line and now I have an opportunity to review one of their products.

Hydra is an application that produces stunning High Dynamic Range photographs. High dynamic range imaging (HDRI) is a process which takes several bracketed exposures of normal digital images and blends them together to produce a photograph that has, well, high dynamic range. It is not quite 3-D but a good HDR photograph can be stunningly life-like. I have included a few samples of non-copyrighted photos that others have taken. You may remember photographs from the 30’s and 40’s in Life magazine of nuclear explosions and the billowing mushroom clouds that were produced. Those striking images were created using the HDR process. There are artificial ways to create images that imitate HDR but a true HDR image is composed of several photographs that are taken using different exposures (bracketing) then they are combined into one image that is properly exposed. You can use Photoshop and other similar editing applications to enhance a digital photo but a true HDR image is made with several different exposures that are blended together. Hydra is one application of several on the market that is capable of producing splendid HDR images with simplicity.

The Creaceed website has two good Hydra 1.6 “Screencast” which are Quicktime tutorials on Hydra Basics and Hydra Blending. I do recommend watching the tutorials first. The User Guide that is downloadable is also well done. Hydra 1.6 works as a stand-alone program or as an Aperture 2.0 plug-in. Version 1.6 includes a plug-in that works with Aperture 2.0. as well as improved Pipeline, DAW, DNG and OpenEXR support. I Hydra 1.6 on my iMac which has a 2.4 GHz processor and running Leopard version 10.5.5.

Preparation is essential to produce a quality HDR image. Photographs may be taken with any camera that has a manual mode which allows different exposures. I have a Canon XSi and it has a bracketing mode which allowed me to take three successive shots at different exposures. I did find in experimenting with Hydra that photos that show multi-dimensional detail work best. Using a tripod is also essential as any change between images will create a blur when blended. You can make minor adjustments but the clarity will be affected. My first sample shots were of trees in their fall colors and of Turnagain Arm but I found these to be too flat. The shots of trees lacked detail and depth that make HDR images pop. It was not windy when I took the photos but it was obvious that the leaves fluttered between shots and the HDR result was a slightly blurry image. Creating HDR images is a deliberate process thus I find this product to be for serious or professional photographers who work at taking “strong” images and when blended in Hydra 1.6 can produce striking results.

Hydra’s interface is simple. Low dynamic range (LDR) photos of the same image but with different exposure levels are shown on the left. You simply “drop” up to 10 LDR images into the Hydra window and they line up on the left. Actually, 10 photos is a bit much, 2-4 LDR photos are recommended. A larger screen to the right displays the current image with a nice mirrored image cast below it. A floating Info Panel (like an inspector panel) contains the tools needed to manipulate images.

The first thing that should be done is to align your images so they will appear as one when blended. Click on the Align button and you’ll see a number of reference points or nodes on the image. I found it helpful to move the reference point to a straight angle on the photo as that helped align the photo to the grid. The goal is to move the nodes around and adjust the position of the photos so that they all line up as close as possible with the grids. I tried this many times and I’m not sure how effective my manual attempts were compared to having Hydra do it automatically.

The next step is to merge the images together. There are slider bars to adjust Exposure, Gamma and Saturation. A handy histogram is also shown to assist in making adjustments. When you’re finished, click Render to create the full resolution output. Your merged HDR will then be exported to iPhoto or to Aperture and you can then take full advantage of the sharing options in these applications. Images can be saved in JPG, TIFF or OpenEXR. OpenEXPR preserves the entire dynamics range and can be be further enhanced using Photoshop or other editing applications. While my first attempts to use Hydra 1.6 produced passable HDR images, using the enhancement tools in Photoshop helped to make them pop. I suspect that many of the HDR images posted on the many sites available on the web have had some editing done post Hydra 1.6

Hydra 1.6 is capable of producing stunning photos that are so realistic to the eye. There are many examples available on various websites and some look almost three dimensional. My experimentation fell short of producing a truly remarkable image but I found the application easy to use and it has great potential. I have a few trips coming up during which I will have an opportunity to take some bracketed shots so I can use Hydra 1.6 to produce cool HDR images. Photos of streams or moving water can be really intriguing as the stationary objects around it will appear in sharp detail and the moving water (due to several exposures) may appear blurred which shows motion. It will be fun to experiment further with some good images. Who knows, you may soon find one of my HDR images created with Hydra 1.6 online! Stay tuned.