Digital BW, The Print

Norman Koren has a great site that explains everything in detail, but is not
for the faint of heart. It requires careful study. While there is a lot of
great info on the site, this link gets you to the dynamic range questions
you are asking about.

http://www.normankoren.com/digital_tonality.html

His site also does a technical comparison of digital and film cameras for
resolution and noise, including the limiting effects of lens resolution. For
digital there is only one lens, but for film there are three lenses of
interest - the camera lens, a scanner lens, or the enlarger lens. It's a
fascinating website. Here is the link for that discussion.
http://www.normankoren.com/Tutorials/MTF.html

Steve
----- Original Message ----- 
From: "Steve Kale" <stevekale@...>
To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
Sent: Tuesday, November 23, 2004 2:09 AM
Subject: Re: [Digital BW] Tonal range recording



Ok so I must confess that this and the other responses blew straight over my
head, not being a zone guy and not understanding film shoulders and toes.
Can I ask some basic questions so that I can follow the discussion:

1)  You speak of 15 stops from colour negative film.  I have heard people
saying that Velvia slide film has just +/- 1 2/3 stops, or 3 1/3 stops, of
workable range.  Are these measurements of the same thing?  (What is the
tonal range of Provia?)

2) How does one convert stops to density? Loosely.  For example, if a
scanner has a rated dMax of 4.8 how does that relate to the tonal range in
stops of film that it is going to scan?

3) Where does the "12 stop linear capability of some censors" come from?
What is the figure for the 1Ds MK II or 1Ds?

4) I think I understand the importance of linearity - kind-of-sort-of - from
printing.  Is this a similar concept? Ie evenly distributed tonal range?

5) At the end of the day we are severely constrained by the tonal range
capability of our printing.  Hogarth mentioned 8 stops for silver gelatin
paper.  How do I relate a linearised print of a step wedge on HPR with a
paper white dMin of .04 and a best black dMax of 1.68 to these figures?
(Wouldn't it be nice if they all used the same scale?)

While the boundaries of the digital print are expanding, I guess we still
need to shoot by compressing the tonal range of the scene with ND filters
(or multiple exposures) so that it can be rendered well in the print -
traditional or inkjet.  I am trying to relate the two (and the steps that
may be in between eg scanning) so that when I get out my spot meter I am not
only thinking in terms of stops but also in terms of my printer's tonal
range.  Sorry if these are basic questions but I think it will help a lot of
people tie all the talk of dMax back to the camera itself.


Thanks

Steve

PS:  this was not meant to be a digital capture vs film capture discussion -
I think the topic relates to both. I do believe there are significant
workflow efficiencies with digital cameras and I am about to make the switch
but relating the tonal range of a scene as measured by a spot meter in
f-stops back to the tonal range of the printer, ink and paper combination
applies to both forms of capture.


> From: <claudej1@...>
>
>
>
> Boy, you have opened a big can of worms here. Most of the color negative
> film (normal C-41 development) has a Contrast Index of 0.44-0.52, which
means
> a
> 1 stop luminance change in the scene records a 0.14 change in density in
the
> film. Assuming no major color crossovers, from a pure monochomatic
conversion
> of  the resultant lumped densities, you can get out to about 15 stops of
> luminance  before a shoulder apperars from the straight line and short toe
of
> color
> neg.  films. This from a Dmin in the shadows of about .25 to a Dmax of r
2.38
> in the  highlights.
>
> B&W films, especially Tmax (per my curve tests circa 1990) can vary  from
> 3-11 stops with D-76 straight (I wild combinaton to tame I might add) and
a
> 5-11
> minute development time. So with B&W, the Contrast Index (CI) varies  with
> development, as does the effective shadow thresholld speed, although not
as
> much as you might think.
>
> ISO states that you need a CI of 0.65 to get the box speed rating. Most
> Zoners develop their filme to a CI of 0.55 to match to the CI of #2 paper,
> which
> is a CI of 1.8 in an ideal world. So ISO essentially "pushes" the film a
> little  to get their rating, but real users have always derated their film
at
> least
> 2/3  stop with their "normal development."  So, with severe speed derating
> and  an extreme development "pull" you can get a lower CI than color neg.
> film,
> which  is fixed. This could also inhibit the Dmax of the film depending on
the
>  developer and how it is agitated.
>
> I have achieved densities in excess of 4.0 with Tmax developed in Dektol
> (not a misprint), but I never tested for linearity.
>
> So, the recordable density range for B&W film varies all over the map  and
is
> not necessarily superior to the 12 stop linear capability of some
sensors.
> Besides, with digital capture, you can easily increase the dynamic  range
with
> a separate highlight and shadow range exposure to be blended later in  any
> ratio you wish.
>
> This makes blanket statements, in either case, untrue without specific
> details of each method.
>
> I prefer the speed and efficiency of digital capture with the
> creative/corrective post processes afforded by Photoshop, but that's just
me.
> I'm too
> impatient to go back to the darkroom for any reason. I earn my living
with
> "click
> to print" workflows of less than 1 minute for a 4x6 color print from  high
> speed dye subs, and I'm starting to do the same with Epsons, so maybe I've
> been
> pulled too far the other way by digital technology.
>
> I simply love color pigments AND BO/Quad/Hex/Sept/Oct monochrome inkjet
> output on various papers. What a great time to be in the "lightroom" with
so
> many
> great choices.
>
> My handcuffs are long gone along with my toxic chemical dependency.
>
> Claude
>
>
> [Non-text portions of this message have been removed]
>
>
>
>
> Please visit the Group Homepage to check the Files, and other resources as
> they are often being updated.
>
> http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint
>
> If you wish to receive no emails or just a daily digest, or you wish to
> unsubscribe, please edit your Membership preferences by visiting this same
> page.
>
> Please follow these basic guidelines:
> - As threads develop, trim off excess portions of earlier messages to keep
> them short.
> - Good manners are required at all time. No personal attacks or flames.
> Hostile, aggressive or argumentative users may be removed from the
membership
> without notice.
> - Keep your posts and threads related to the group topic of digital B&W
> printing. Users who persistently make off-topic posts may be removed from
the
> membership.
> - By posting on this forum you agree to abide by the group rules and
> guidelines, and to abide by the actions and decisions of the group Owner
and
> Moderators. See \u201eGroup Topic, Rules and Guidelines\u2030 in the Files section:
> http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/files/
>
> BY PARTICIPATING IN AND/OR POSTING MESSAGES TO THE DIGITAL BW, THE PRINT
> YAHOO! GROUP YOU EXPRESSLY UNDERSTAND AND AGREE THAT THE \u201eOWNER\u2030 AND
> \u201eMODERATORS\u2030 OF DIGITAL BW, THE PRINT YAHOO GROUP SHALL NOT BE LIABLE TO
YOU
> FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL OR EXEMPLARY
> DAMAGES, INCLUDING BUT NOT LIMITED TO, DAMAGES FOR LOSS OF PROFITS,
GOODWILL,
> USE, DATA OR OTHER INTANGIBLE LOSSES (EVEN IF THE  \u201eOWNER\u2030 AND
\u201eMODERATORS\u2030 OF
> DIGITAL BW, THE PRINT YAHOO GROUP HAVE BEEN ADVISED OF THE POSSIBILITY OF
SUCH
> DAMAGES), RESULTING FROM: (i) THE USE OR THE INABILITY TO USE THE DIGITAL
BW,
> THE PRINT YAHOO GROUP; (ii) UNAUTHORIZED ACCESS TO OR ALTERATION OF YOUR
> TRANSMISSIONS OR DATA; (iii) STATEMENTS OR CONDUCT OF ANY THIRD PARTY ON
THE
> DIGITAL BW, THE PRINT YAHOO GROUP; OR (iv) ANY OTHER MATTER RELATING TO
THE
> DIGITAL BW, THE PRINT YAHOO GROUP.
>
> Yahoo! Groups Links
>
>
>
>
>
>
>





Please visit the Group Homepage to check the Files, and other resources as
they are often being updated.

http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint

If you wish to receive no emails or just a daily digest, or you wish to
unsubscribe, please edit your Membership preferences by visiting this same
page.

Please follow these basic guidelines:
- As threads develop, trim off excess portions of earlier messages to keep
them short.
- Good manners are required at all time. No personal attacks or flames.
Hostile, aggressive or argumentative users may be removed from the
membership without notice.
- Keep your posts and threads related to the group topic of digital B&W
printing. Users who persistently make off-topic posts may be removed from
the membership.
- By posting on this forum you agree to abide by the group rules and
guidelines, and to abide by the actions and decisions of the group Owner and
Moderators. See Group Topic, Rules and Guidelines in the Files section:
http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/files/

BY PARTICIPATING IN AND/OR POSTING MESSAGES TO THE DIGITAL BW, THE PRINT
YAHOO! GROUP YOU EXPRESSLY UNDERSTAND AND AGREE THAT THE OWNER AND
MODERATORS OF DIGITAL BW, THE PRINT YAHOO GROUP SHALL NOT BE LIABLE TO YOU
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL OR EXEMPLARY
DAMAGES, INCLUDING BUT NOT LIMITED TO, DAMAGES FOR LOSS OF PROFITS,
GOODWILL, USE, DATA OR OTHER INTANGIBLE LOSSES (EVEN IF THE  OWNER AND
MODERATORS OF DIGITAL BW, THE PRINT YAHOO GROUP HAVE BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES), RESULTING FROM: (i) THE USE OR THE INABILITY
TO USE THE DIGITAL BW, THE PRINT YAHOO GROUP; (ii) UNAUTHORIZED ACCESS TO OR
ALTERATION OF YOUR TRANSMISSIONS OR DATA; (iii) STATEMENTS OR CONDUCT OF ANY
THIRD PARTY ON THE DIGITAL BW, THE PRINT YAHOO GROUP; OR (iv) ANY OTHER
MATTER RELATING TO THE DIGITAL BW, THE PRINT YAHOO GROUP.

Yahoo! Groups Links