HDR - High Dynamic Range.
HDR is a set of methods used in imaging and photography to allow greater dynamic
range between the lightest and darkest areas of an image.
HDR images can represent more accurately the range of intensity levels found in real
scenes, from direct sunlight to faint starlight.
Non-HDR cameras take pictures at one exposure level with a limited contrast range.
This results in a loss of detail in bright or dark areas of a picture depending on whether
or not the camera had a high or low exposure setting.
HDR compensates for this loss of detail by taking multiple pictures at different exposure
levels and correctly blending them together so that the picture is representative in both
dark and bright areas.
This can be achieved in several ways :-
1. Process of image manipulation in Photoshop, Paintshop pro,
etc ( photomerge).
2. Processing by a dedicated HDR software program like Photo
Matrix.
Which ever software you use you will need three exposures of the same image, for
example one underexposed ( -1.5), one correctly exposed (0) and one over exposed
(+1.5).
Always set your camera to aperture mode as some software find its difficult to blend
photos with different depth of fields, so by keeping your aperture fixed all your photos
should have the same amount of the scene in focus.
Photo Matrix is a nice little piece of software available as a stand alone package or as
a plug-in for photoshop, from the website you can download a trial version but the
resulting image will carry the Photo Matrix water mark.
Firstly, the camera - with a Canon DSLR you can set your bracketing from the camera
menu windows, set to -1.5 0 ,+1.5, this will allow you to capture 3 photographs at different
exposures with 3 separate activation's of the shutter. You can also set the camera to
capture RAW+Jpeg and adjust your exposures from the raw file saved by the camera.