Black point & white point in photo editing software

[UncleBen]

Hi,

Moving from film to digital, I'm overwhelm with all the functionality available in the digital darkroom.

I recently came across the black point & white point (also grey point). I read & gathered the following on how to define both from the internet & am confused:

1) define black point as 7 & white point at 247.
2) move the slider (in below the histogram) until you see the first "meaningful" black & white & sample it.
3) move the slider (in below the histogram) until you see the first black & white & sample it.

I am wondering if these are applicable for different scenarios?

For discussion, lets take a simple example of a person wearing white T & black pant, standing under a tree with a small area of deep dark shadow at the bottom & another small area of overexposed on the sky.

Which is a better point to sample for the black & white?

What about a photo of a night cityscape/landscape? Do you guys normally set the black & white point? Or there are other ways of achieving the same effect?

Thanks in advance.

Cheers,
Ben

 

[UncleBen]

Anyone?

Did I post this in the wrong place?

Cheers,
Ben

 

[Octarine]

Have a look at the entire forum .. and you'll find "Digital Darkroom"

 

[Squid]

Moving from film to digital, I'm overwhelm with all the functionality available in the digital darkroom.

I recently came across the black point & white point (also grey point). ......

For discussion, lets take a simple example of a person wearing white T & black pant, standing under a tree with a small area of deep dark shadow at the bottom & another small area of overexposed on the sky.

Which is a better point to sample for the black & white?

Welcome to digital world where a photographers does own image processing. I'm not sure what image processing software that you are using. To reply to this thread, I am using CaptureNX examples as one of them comes close to your requested example.

On Nikon CaptureNX2 http://www.capturenx.com/en/lessons/bandwcontrol/index.html and http://www.capturenx.com/en/intuitive_operation/wbn/index.html, there are demonstration of the effect of black-and-white point selection and its effect. Note, in actual situation, accurate point selection vastly improves overall contrast level of an image and inaccurate point selection make a picture overly contrasty, as black-and-white-points selection is considered a "blunt" tool.

Alternatively, you may choose to rely on typical "auto-contrast" function in most image processing software which work most of the situation, based on my personal experience.

I recently came across the black point & white point (also grey point). I read & gathered the following on how to define both from the internet & am confused:

1) define black point as 7 & white point at 247.
2) move the slider (in below the histogram) until you see the first "meaningful" black & white & sample it.
3) move the slider (in below the histogram) until you see the first black & white & sample it.

I am wondering if these are applicable for different scenarios?

Exact black point and white point vary from image to image. There is no fix setting. See CaptureNX examples mentioned earlier.

What about a photo of a night cityscape/landscape? Do you guys normally set the black & white point? Or there are other ways of achieving the same effect?

See CaptureNX example on http://dptnt.com/2007/12/quick-and-easy-landscape-workflow-with-capture-nx/

 

[osocan]

Hi,

Moving from film to digital, I'm overwhelm with all the functionality available in the digital darkroom.

I recently came across the black point & white point (also grey point). I read & gathered the following on how to define both from the internet & am confused:

1) define black point as 7 & white point at 247.
2) move the slider (in below the histogram) until you see the first "meaningful" black & white & sample it.
3) move the slider (in below the histogram) until you see the first black & white & sample it.
I am wondering if these are applicable for different scenarios?

For discussion, lets take a simple example of a person wearing white T & black pant, standing under a tree with a small area of deep dark shadow at the bottom & another small area of overexposed on the sky.

Which is a better point to sample for the black & white?

What about a photo of a night cityscape/landscape? Do you guys normally set the black & white point? Or there are other ways of achieving the same effect?

Thanks in advance.

Cheers,
Ben

I think I read that in Scot Kelby's book. It's for removing colour cast in the photo. As for the white point, he suggested not to sample from specular highlights. He didnt elaborate on the black point. I suppose it depends on how much shadow details you wanna retain.

 

[UncleBen]

Thanks for the heads up, folks.

Very much appreciated your help.

Digital post processing......still a long journey for me.

Cheers,
Ben