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From: David Nebenzahl on
After my recent success with TMX, I delved into my freezerful of film
and pulled out a roll of Pan F I want to shoot. But I'm a bit mystified
by the enclosed processing instructions.

Was thinking of using D-76, and they have times for both this and ID-11
(same times, since the same developer, except that they list ID-11 at
1+1 but not D-76, though I assume I can also dilute it). But they show
the same times for both ISO 25 and 50 exposure. Can this be correct?
Other developers show different times for the two speeds.

They also show times for Perceptol, but not Microdol-X. Richard K., you
said these developers were equivalent: would you use the same times for
both of these? The Humumgous Massive Really Really Big Dev Chart
(http://www.digitaltruth.com/devchart.php) shows different times for
these (9 min. for Perceptol vs 12 min. for Microdol; should I just use
their recommendations?


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)
From: IanG on

The MDC is not as reliable as the Manufacturers own data because we
don't know who or how the poster reached their figures.

Ilford's Data is here and a far better starting point.

http://www.ilfordphoto.com/Webfiles/2006216115811391.pdf

Ian

David Nebenzahl;884098 Wrote:
> After my recent success with TMX, I dTHe MDC is unfortunately not elved
> into my freezerful of film
> and pulled out a roll of Pan F I want to shoot. But I'm a bit mystified
>
> by the enclosed processing instructions.
>
> Was thinking of using D-76, and they have times for both this and ID-11
>
> (same times, since the same developer, except that they list ID-11 at
> 1+1 but not D-76, though I assume I can also dilute it). But they show
> the same times for both ISO 25 and 50 exposure. Can this be correct?
> Other developers show different times for the two speeds.
>
> They also show times for Perceptol, but not Microdol-X. Richard K., you
>
> said these developers were equivalent: would you use the same times for
>
> both of these? The Humumgous Massive Really Really Big Dev Chart
> (http://www.digitaltruth.com/devchart.php) shows different times for
> these (9 min. for Perceptol vs 12 min. for Microdol; should I just use
> their recommendations?
>
>
> --
> The fashion in killing has an insouciant, flirty style this spring,
> with the flaunting of well-defined muscle, wrapped in flags.
>
> - Comment from an article on Antiwar.com (http://antiwar.com)




--
IanG
From: Digitaltruth on
The Massive Dev Chart is more reliable than the published data sheets
released by manufacturers. Why? Because it incorporates the official
information that you will find in the manufacturer's data sheets, AND
it includes additional user submissions and amendments. I've spent 15
years collating and editing this data, which is a lot more time than
the manufacturers spend on it.

While some manufacturers, most notably Ilford and Fuji, provide
excellent data based on their own in-house analysis, many other
manufacturers are far less thorough. In fact, there are several
official data sheets currently being published which include data from
the Massive Dev Chart as the primary source, even though I doubt the
manufacturers have ever tested it themselves.

One of the recurrent questions about the Massive Dev Chart is why
Ilford's published times for developing film in Kodak D-76 are only
included if they are the same as the published times for ID-11. The
reason for this is because the chemical composition of these two
developers is almost identical. In fact, the difference is
sufficiently small so as to be negligible for all intents and
purposes. Ilford's data for its own products is highly reliable, so
when there is a significant variance between times for third-party
chemicals such as D-76, then it is safe to assume that the testing
procedure was different and should not be relied on if it does not
match that of ID-11.

Perceptol and Microdol-X are not the same developer, although they
have similar characteristics. Different times are required, so you
should use the data for each developer in The Massive Dev Chart to
provide the required starting point.

If you study official data sheets you will notice that manufacturers
often update the times even though no changes have been made to their
products. Conversely, Kodak changed many times when they modified the
film base on several products a few years back, but other published
studies showed that the original times were more accurate. You can
also see that, famously in the case of Agfa, they release different
data in different countries. Trusting something just because it is
printed by the manufacturer is does not offer any guarantee of
accuracy.

The most important part of any issues regarding accuracy of
development times is to understand that ALL times are starting point
recommendations, regardless of the source, and it is up to the
individual user to use these starting points to determine the optimum
development in relation to subject contrast, print contrast and
enlarging equipment.

--Jon Mided

http://www.digitaltruth.com

From: David Nebenzahl on
On 7/22/2010 11:39 AM Digitaltruth spake thus:

> The Massive Dev Chart is more reliable than the published data sheets
> released by manufacturers. Why? Because it incorporates the official
> information that you will find in the manufacturer's data sheets, AND
> it includes additional user submissions and amendments. I've spent 15
> years collating and editing this data, which is a lot more time than
> the manufacturers spend on it.
>
> While some manufacturers, most notably Ilford and Fuji, provide
> excellent data based on their own in-house analysis, many other
> manufacturers are far less thorough. In fact, there are several
> official data sheets currently being published which include data from
> the Massive Dev Chart as the primary source, even though I doubt the
> manufacturers have ever tested it themselves.

[snip]

Well, I for one very much appreciate, and have made much use of, your
Humungous Ginormous Dev Chart. My hat is off to you.

And as I pointed out in another post here, some of Ilford's own
documentation has obviously erroneous data: both the inside of the film
carton and the large Ilford Film Processing Chart that I have show
identical (and therefore obviously incorrect) times for ISO 25 & 50
times for three different developers for Pan F.

Your chart agrees perfectly with the Ilford PDF supplied elsewhere in
this thread, which appears to be correct.


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)
From: Richard Knoppow on

"Digitaltruth" <info(a)digitaltruth.com> wrote in message
news:ef856680-1340-4387-a900-9f4e1ae1effb(a)d17g2000yqb.googlegroups.com...
> The Massive Dev Chart is more reliable than the published
> data sheets
> released by manufacturers. Why? Because it incorporates
> the official
> information that you will find in the manufacturer's data
> sheets, AND
> it includes additional user submissions and amendments.
> I've spent 15
> years collating and editing this data, which is a lot more
> time than
> the manufacturers spend on it.
>
> While some manufacturers, most notably Ilford and Fuji,
> provide
> excellent data based on their own in-house analysis, many
> other
> manufacturers are far less thorough. In fact, there are
> several
> official data sheets currently being published which
> include data from
> the Massive Dev Chart as the primary source, even though I
> doubt the
> manufacturers have ever tested it themselves.
>
> One of the recurrent questions about the Massive Dev Chart
> is why
> Ilford's published times for developing film in Kodak D-76
> are only
> included if they are the same as the published times for
> ID-11. The
> reason for this is because the chemical composition of
> these two
> developers is almost identical. In fact, the difference is
> sufficiently small so as to be negligible for all intents
> and
> purposes. Ilford's data for its own products is highly
> reliable, so
> when there is a significant variance between times for
> third-party
> chemicals such as D-76, then it is safe to assume that the
> testing
> procedure was different and should not be relied on if it
> does not
> match that of ID-11.
>
> Perceptol and Microdol-X are not the same developer,
> although they
> have similar characteristics. Different times are
> required, so you
> should use the data for each developer in The Massive Dev
> Chart to
> provide the required starting point.
>
> If you study official data sheets you will notice that
> manufacturers
> often update the times even though no changes have been
> made to their
> products. Conversely, Kodak changed many times when they
> modified the
> film base on several products a few years back, but other
> published
> studies showed that the original times were more accurate.
> You can
> also see that, famously in the case of Agfa, they release
> different
> data in different countries. Trusting something just
> because it is
> printed by the manufacturer is does not offer any
> guarantee of
> accuracy.
>
> The most important part of any issues regarding accuracy
> of
> development times is to understand that ALL times are
> starting point
> recommendations, regardless of the source, and it is up to
> the
> individual user to use these starting points to determine
> the optimum
> development in relation to subject contrast, print
> contrast and
> enlarging equipment.
>
> --Jon Mided
>
> http://www.digitaltruth.com
>
If you check the MSDS you will find that Microdol-X and
Perceptol are essentially identical. I say essentially
because both manuacturers probably have additions in the
form of sequestering agents that do not show up in MSDS.
Also, Kodak has patented method of preparing some of the
ingredients they use. The published formulas for D-76 and
ID-11 are the same but the packaged developers may be
different. The MSDS for D-76 shows it to be the buffered
formula similar to the published D-76d. Packaged ID-11 may
also be buffered but no buffering agent shows up in the
MSDS.
Manufacturers' data is generated by use of proper
sensitometry, at least its supposed to be and I think Kodak
and Ilford data are reliable. One difference between the two
is that some time ago Ilford stopped using the ISO method to
rate film. The ISO standard is correct for a contrast index
about right for diffusion enlarging and contact printing.
When lower contrast is desired for condenser enlargers the
development must be adjusted with a consequent change in
effective film speed. Ilford appears to use a contrast index
mid-way between condenser and diffusion values. This results
in a slight lowering of effective speed when the film is
developed to diffusion contrast and accounts for the
differnce in developing times for Ilford film given by
Ilford and some others.


--
--
Richard Knoppow
Los Angeles, CA, USA
dickburk(a)ix.netcom.com


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