Jacques Augustowski (jacquesa@acd.ufrj.br)
Sat, 23 Jan 1999 17:14:01 -0300 (GRNLNDST)
Rodrigo,
I'm in Brazil. Just e-mail me or call me at 0212595970.
Jacques
On Fri, 22 Jan 1999, Rodrigo Whitaker Salles wrote:
> At 13:12 21/01/99 -0500, you wrote:
> >In a message dated 1/21/99 2:12:46 AM Pacific Standard Time,
> >rwsalles@provida.org.br writes:
> >
> >> Considering a normal development, what step in the T-14 corresponds to a
> >> neutral 18 %gray card ?
> >
> >I am not sure if you are asking the density of a gray card, or if you are
> >asking what the density of the film should be if you shoot a gray card with
> >exposure metered with the gay card (for zone system calibration). I
> believe it
> >is the latter. Since this is not directly related to alt. process, I will
> >answer briefly. Feel free to contact me offlist if you have more questions.
> >
> >For zone calibration, you need to find not just the development to produce
> the
> >right density, but also the system speed. In brief, the following is the aim:
> >
> >gray card minus 4 stops (underexposed) should give 0.1 + base+fog
> >gray card plus 2 stops (overexposed) should give approx. 1.05 + base + fog
> >
> >base+fog is different from film to film, so make sure you account for that.
> >For example, b+f of TMax100 roll film is about 0.24.
> >
> >You can then compare your target value with a step tablet. Cor has listed the
> >densities of the steps, so I won't repeat.
> >
> >
> >Dave
>
> Thank you Dave and Cor for your answers.
>
> The problem I face is: "how should I calibrate my system (lens, shutter
> speeds, agitation method, enlarging method - mine is by condensers - with
> Bergger 200 Film developed with PMK?" I've been reading many books on the
> subject, but I confess I'm trying to mix alt processes with zone system. I
> don't know any lectures or masters on the matter here in Brazil who could
> show any hint, so all I have are books (in english) and good willing people
> like you.
>
> I know this is a basic question, perhaps it shouldn"t be here, but I think
> it is related to alt processes as well, since I must get negatives of
> contrast range about 1.8 to 2.0 for both cyanos and Pt/Pd.
>
> Anyway, thanks to both of you and others who answered my questions.
>
>
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