My camera has Dual Pixel RAW, but I’ve never used it and wondered what it is, and when would it be useful?
Chester Pickering, Farnham
BRIAN SAYS… Canon uses two photo diodes within each pixel as part of the dual-pixel AF system, and when Dual Pixel RAW is enabled, the light level measured by each photo diode is saved in the RAW image. This means that such images are twice as large and can limit the maximum shooting rate, too.
When a scene is viewed from two slightly different perspectives, it is slightly different – you can see this by looking at a scene with your left eye and then right eye individually. Dual Pixel RAW is similar and Canon’s Digital Photo Professional software can leverage the two viewpoints to perform corrections to an image: image microadjustment, bokeh shift and ghosting reduction. The EOS R5 and EOS R6 Mark II also have in-camera Dual Pixel RAW processing functions to adjust background clarity and perform portrait relighting.
Image microadjustment slightly repositions the point of maximum sharpness in an image taken with a fast lens at maximum aperture, but the shift is minimal. Bokeh shift moves the bokeh in front of and behind the subject. Ghosting reduction can reduce reflections when shooting through glass.
In-camera background clarity brings more detail out of backgrounds; this might be needed when a wide aperture was used to take the shot but some detail needs to be recovered from the background. Perhaps more interesting is portrait relighting, where it is possible to move the apparent light source around a detected face in the frame to change how it appears to be lit. It is also possible to change the apparent size of the light source to even out the results. Edited in camera images are saved as new JPEGS.