Dynamic range and RAW file "bit depth"

Started 11 months ago | Questions thread
DSPographer
Senior MemberPosts: 2,419Gear list
Like?
Re: having pondered this, why not have 17 bit raw file option?
In reply to Jack Hogan, 11 months ago

Jack Hogan wrote:

DSPographer wrote:

This isn't just wasteful of file bits, it also could significantly slow down the raw converter. In column parallel ramp converters like Sony's Exmor sensors use, having a nonlinear ramp dramatically speeds up the conversion process. So, on many cameras that have "14-bit" raw capability the conversion step size is not really uniform, instead it increases approximately as the square root of the level, so that the time to perform the ramp conversion is not excessive.

Hi DSPographer,

Interesting. How does having a non-linear ramp affect accuracy of the linear ADC output throughout the range?

Here is a paper which discusses non-linear ramp converters of the sort Sony uses in their Exmor sensors:

http://www.imagesensors.org/Past%20Workshops/2005%20Workshop/2005%20Papers/44%20Otaka%20et%20al.pdf

 DSPographer's gear list:DSPographer's gear list
Canon PowerShot G7 X Canon EOS 5D Mark II Canon EF 24mm f/2.8 Canon EF 50mm f/1.8 II Canon EF 200mm f/2.8L II USM +4 more
Reply   Reply with quote   Complain
Post (hide subjects)Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark post MMy threads
Color scheme? Blue / Yellow