Digital BW, The Print

> Could you elaborate a bit on "all the way to the right"? I'm close to 
> following
> you, but not quite there :-) Thanks!
> Scott

It's best if I send you to the source.

Here's a post from the Adobe link: http://www.adobeforums.com/cgi-bin/webx?
14@...2v9Dp0.31@.3bb6a869.3bbb1172/24:


Bruce Fraser wrote on - 4:16pm Jul 1, 05 PST (#28 of 125)	

"DSLRs don't have that highlight compression, and Zone V is way down around 50 or so on 
a 0-255 scale. Fully half the data the camera captures is devoted to describing the 
brightest f-stop the camera can record at the selected exposure/ISO settings. If you 
underexpose, and hence fail to populate that range with captured data, you're only 
capturing half the tones the camera can record, and you'll be fighting posterization and 
banding when you try to redistribute the captured data across the whole tonal range. 

You're always going to get better results with digital capture when you stretch the 
highlights, darkening the midtones and shadows, than you will by compressing the 
highlights and lightening the midtones and shadows, because the camera captures much 
more highlight detail than we can see, and much less shadow detail than we can see. 

Within limits, digital raw give you a huge degree of latitude in where you place the 
midtone, but those limits are imposed by where you set the highlight point. Everything 
hangs off the highlights, so the key decision you need to make when exposing for digital 
capture is where you want to set your highlight point. That's why I spot-meter on the 
highlights. 

The tone response of the sensor medium is the biggest and most confusing difference 
between film and digital. Film behaves approximately like eyeballs. Digital capture doesn't, 
not even vaguely. A useful exercise in trying to get your head around this—at least it 
helped me a lot, is to make a linear-gamma grayscale gradient, and watch what happens 
as you shove the bits around to try to make it approximately perceptually uniform. 

Digital isn't panchromatic either—it's way more sensitive to red and IR than it is to blue 
and UV—basically the opposite of film—but that's a much smaller issue than the difference 
between a perceptually-weighted response and a linear one." 

Here's another post from: http://www.adobeforums.com/cgi-bin/webx?
14@...2v9Dp0.33@.3bb6a869.3bbb1172/35

Jeff Schewe wrote - 8:52am Jul 2, 05 PST (#42 of 125)		
"So what you really want to do is spot-meter the highlights, and expose for a middle gray 
that preserves the highlights. There are probably no lightmeters that will do that 
calculation for you." 

EXACTLY!!! 

Thank you for finding the exact words. . . 

Yes, the ideal would be to spot meter the highlights that you wish to have textural detail 
and expose to just get that texture without clipping. 

Because digital captures are linear, there is an incredible amount of detail in that brightest 
1 stop of a scene. Looking at the LCD on the back of the camera as a preview or even 
looking at the histogram (which tells you little that's useful) will not really tell you what is 
textural highlights vs specular highlights intended to clip. 

One of the reasons Thomas put in the curves function of Camera Raw 3.x was because he 
was convinced by several people (Bruce and Steve Johnson in particular) that there was so 
much data there in the highlights that only a custom curve function could allow 
reditribution or useful data and only in the linear stage, not after the image has been 
processed into a gamma encoding. 

Admitedly, this whole dicussion is about taking digital to the max-the flexibility of raw 
captures, the power of Camera Raw and processing in Photoshop allow SOOOO much 
control of the tone distribution of digital photography that I suspect many people will see 
this as a waste of time. And, to be honest, depending on what you are shooting and why, 
it could well be. 

But I thought it would be useful to try to explain exactly why digital capture ain't the same 
as film. . .particularly in the why optimum exposures are determined. 

 Also it's fun to remember my old college days and try to make some use of my old 
darkroom skills. 

" I remember a film rated at ASA 250 that responded admirably, but way too grainy, even 
in 4x5. " 

Royal Pan-X is what I think you remember and yes it was a wonderful film for contrast 
control as long as you were only making contact prints. The grain did look like boulders!"