High Dynamic Range (HDR) & Infra-red

I have, on the odd occasion, used the HDR technique with colour images, particularly in tricky lighting situations to guarantee a good shot. To achieve this greater latitude you bracket your exposure by 1 or 2 stops over 3 or more frames, thus recording detail in both highlight and shadow areas. It is important to remember to alter your shutter speed and not the aperture, which would result in your image being out of focus. With your consecutive frames safely recorded you will need to blend them together. Photoshop™ has the ability to do this for you; File>Automate>Merge to HDR or you can use the well known HDR Programme; PhotoMatix Pro, now in version 3.0.3RC2. A valuation copy can by downloaded from their website: www.hdrsoft.com

This HDR technique can also be used to capture Infra-red images. The process is just the same; capture a sufficient number of exposures to properly cover the dynamic range of the scene, from the darkest shadows to the brightest highlights. Use a tripod at all times, shoot with available light whenever possible as flash may try to balance the exposure of all the images, when a range of exposures is your goal.

It is important to remember that the number of exposures needed depends on the dynamic range of the scene. For most outdoor scenes, three exposures taken at +/- 2 exposure increment will be sufficient, provided the scene does not include the sun.

Here is a couple taken with the Nikon D50 using the standard kit lens and Hoya R72 filter.

Because I thought them strikingly different I decided to leave them in colour. However, the monochrome ones I did are noticeably pleasing too.

Use the Infra-red Archive to discover more about the world of Infra-red Photography