What IS luminence, value, etc.?

[Raymond Howard Rich]

Okay, the way I understand it the sensor essentially gathers the number of red, green and blue pixels. So where do the other numbers come from? There has to be a text that explains these numbers and how to derive them. Where is it? What is its name? How do I get one? I would absolutely LOVE to see the structure (C programmers know what I mean) of a jpg image.

[teaking]

** EDITED** ... My below post is rubbish!! lol im talking about something completely different than what this thread is about

Luminance is part of the colour information for example white in RGB is R=255 G=255 B=255 in HSL it is Hue, Saturation and luminance to get to the same colour its more of a 3D way to plot colour as you have a circle you choose your hue rotating around the outside then the saturation which brings the point in or out and then the luminance takes the point up or down I think!!! lol or its the other way round. its like LAB is another different way to profile or choose colour.

[RichardTaylor]

See here for a good explanation of luminance.

Understanding Digital Camera Histograms: Luminance and Color

[inkista]

Originally Posted by Raymond Howard Rich

I would absolutely LOVE to see the structure (C programmers know what I mean) of a jpg image.

JPEG - Wikipedia, the free encyclopedia

And I warn you, it's a bit more complex than a simple struct declaration. And JPEG is just the codec standard. The file format standards are more covered by JFIF and EXIF. If the acronym ends in "IF", it's usually a file format thing, because it usually standards for "interchange format".

You want the techie goods on Canon camera features, btw, Canon puts their white papers up on their website:

http://www.usa.canon.com/dlc/control...articleID=1787

[Raymond Howard Rich]

Thank you very much!