megapixels and post-processing algorithm performance

Started May 8, 2014 | Discussions thread
hjulenissen Senior Member • Posts: 2,106
Re: megapixels and post-processing algorithm performance

Alex Notpro wrote:

"All things being equal" e.g. assuming both images are captured by a state-of-the-art Bayer CFA sensor based camera system, and assuming both images are eventually downsized for a standardized output device...

Sounds pretty much like the DXO "print" option?

Does an abundance of megapixels in an image enable certain post-processing algorithms (e.g. noise reduction, sharpening, aberration correction, distortion correction, tone mapping, shadow/highlight recovery, perspective correction, saturation adjustment, contrast adjustment) to produce higher-quality results than they would from a lower-megapixel image?

1. Higher (sensor) spatial resolution in itself does have some advantages. If the (individual color channel) sensor passband far exceeds the combined passband of lens, OLPF, camera/scene movement etc, then you will have (in the limit) no aliasing. This means less errors even in lower frequencies (such as would be presented in e.g. a webpage). Further, when the sensor samples everything of interest that the lens "delivers", then we have a nearly perfect digital representation of the lens output, and can work on fixing lens flaws without having to fix sensor flaws at the same time (e.g. deconvolution).

2. Higher (sensor) spatial resolution may not be possible without some sacrifices. To some degree, the sensor total active area may be reduced, the needed micro lenses might reduce the benefit of large-aperture lenses (or wide-angles), the sensor might be hotter,.... All of theses are product/technology-specific factors, and I think that few of us can really _know_ to what degree they affect the camera design. What we can do is compare the cameras actually available and make our choices based on that.


Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow