I'm very certain that if I go to a car dealer and walk out with a stack of sales pamphlets none of those images were done with a Canon or a Nikon DSLR
Wrong
I know a couple of the photographers for Audi. They have people within their group, and other contracted services that use Canon and Nikon DSLR equipment to shoot photos for media information, and for brochures. Some of them also do work for Porsche as well.
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EXIF Data
File size : 173507 bytes
File date : 2006:12:07 15:28:58
Camera make : Canon
Camera model : Canon EOS-1Ds Mark II
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EXIF Data
File size : 209064 bytes
File date : 2006:09:02 20:35:31
Camera make : Canon
Camera model : Canon EOS-1D Mark II
Figured I would slip in a Saab for good measure
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EXIF Data
File size : 1014319 bytes
File date : 2005:11:09 01:13:04
Camera make : Canon
Camera model : Canon EOS-1DS
And an Opel
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EXIF Data
File size : 2335429 bytes
File date : 2005:10:20 10:36:01
Camera make : NIKON CORPORATION
Camera model : NIKON D100
Many many more examples if needed. But rest assured car manufacturers use "normal" DSLR cameras for images within brochures, and the discerning press.