[Leica] thinking Zone System

[philippe.amard at sfr.fr (philippe.amard)]

Thanks George for explaining the method.
The sensor EV range is a good start, but the approcach might be  
further developed I guess.
What I'm thinking right now is that I should perform this kind of  
experiment and note to what extent the colours shift in the (post)  
process so that I could anticipate more on colour reliability when the  
shot is within sensor dynamics.

Thanks again , that's excellent food for thought and experimentation.
Bien amicalement
Philippe

Le 9 nov. 10 ? 17:51, George Lottermoser a ?crit :

>
> Tarek,
> When I shot film I used all formats:
> sheets from 4x5 up to 12x20,
> 120 rolls from 6x6 to 6x9,
> and of course 35 mm.
> So I saw Zone System thinking, processing and testing
> as the way to achieve predictable results with Black and White.
> I use a spot meter to read the dynamic range of the subject;
> exposing for the shadow detail I want to preserve;
> and developing for the highlight detail I want to preserve;
> and then having a pretty good idea of where the other tones will fall.
> With 3 120 film backs I was able to carry an N, N-1 and N+1 back.
> With 35 mm I'd carry two camera bodies - an N and N-1 body
> (and if exposing an entire roll under the same dynamic range  
> conditions
> I'd be able to process accordingly ++ or - - or whatever).
>
> Zone system thinking translates to color film as well.
> Except only in terms of understanding the dynamic range of the film
> and knowing how to expose for the highlight detail you wish to  
> preserve;
> and knowing where the shadows will fall to black without detail.
> Of course various emulsions have different dynamic ranges.
>
> Lluis and Tarek,
> With digital I think in similar terms to color film.
> What is the dynamic range of the sensor?
> in order to place the highlights where I want them
> and know where the shadows will fall.
> Further: knowing I have some limited possibilities to extend both  
> ends in post processing.
>
> For example:
> Expose an evenly lit turkish towel (great texture) as metered (zone  
> V).
> Increase the exposure in one stop increments to determine when the  
> highlight detail disappears.
> Decrease the exposure in one stop increments to determine when the  
> shadow detail disappears.
> Through testing I have determined that
> the DMR has approximately 9.5 stops from deep shadow detail to  
> bright highlight detail;
> below that is solid black; above that is solid white.
> This is about 1 1/2 stops more dynamic range
> than the M8; which has about 8 stops from deep shadow detail to  
> bright highlight detail.
> And the 5D has about 7 1/2 stops from deep shadow detail to bright  
> highlight detail.
> I say "approximately" and "about" because
> different levels and types of lighting; ISO settings; and yes lenses
> will have effects on these numbers.
>
> If you want to get really crazy
> you can bring these test shots into photoshop
> and read the values (just like we used to do with a densitometer).
> It's an interesting exercise because you'll find greater separation  
> between some zones than others;
> a little freaky actually.
> (I no longer get that crazy)
>
> Lluis,
> I don't know if anyone else is writing about or discussing digital  
> work flow in terms of the Zone System.
> This is simply my own way of understanding the equipment I'm working  
> with;
> and my way of thinking about the more critical work that I do.
> Just a natural shift from what I grew up with to what I'm doing now.
>
> Others use the histogram to accomplish the same thing.
> I find histograms hard to interpret when the subject has a whole lot  
> of black or a whole lot of white in the frame.
> Though I can always rely on my spot meter to tell me what is  
> actually being recorded and where things will fall.
>
> YMMV
>
> Hope this helps
>
> Regards,
> George Lottermoser
> george at imagist.com
> http://www.imagist.com
> http://www.imagist.com/blog
> http://www.linkedin.com/in/imagist
>
>
>
>
>
>
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