Tmax 100 what is REAL ISO
Dana Rees
>It is irritating, but Kodak ISO ratings on Tmax can't be trusted!
>
>What ISO rating do you-all use? 80? 60?? 58 2/3???
>
>--
>S. Hardy
>
>
That is a good question? What developer do you use, what concentration,
what light meter, what shutter?
Last I knew Kodak only tossed a speed of 100 out as a starting point, I
don't think the film has been rated. You will see a marked difference
in working speed if you use TMax(RS) developer as opposed to HC-110 1:15
from stock solution, or Microdol X, or D-76 1:1.
The film has almost no toe, is sensitive to processing changes, a couple
of degrees or different agitation will greatly change your contrast, and
is sensitive to over development!
It is an incredible film. Once you learn to love it.
Good Luck
Dana R.
Scott Hardy
Donald Nelson -FT-~
In article <3qgtlh$3...@galaxy.ucr.edu>, abr...@cs.ucr.edu (Andrew Brown) writes:
>
> Dana Rees (da...@wordperfect.com) wrote:
>
>
> : That is a good question? What developer do you use, what concentration,
>
> T-MAX developer.
>
> I've never had any problems with the T-MAX series of films. Heck, I pushed
> the 400 to 3200 and it came out fine. :)
>
> Andrew Brown
>
>
Most of us that are concerned about fine art B&W do a small amount of testing.
For sheet film (4x5, 8x10), the actual ISO found by most people is
in the range of 40 or 50 or 64 with most developers. TMAX RS, on the other
hand, yields an effective ISO of 80 for most people.
If you really don't care about what you image shadow detail looks like,
you can always use it at the recommended ISO of 100 and develop it using
the "recommended" development dilutions and times. As Kodak's literature
says, it will result in an "acceptable" imag. ....but you might not
really like what you get if you are interested in fine art as opposed to
snap shooting.
--
ALL OPINIONS EXPRESSED ARE MY OWN AND NOT NECESSARILY THOSE OF INTEL CORP.
DON NELSON
randy libersky
writes:
accurate test for film speed
Jerry Gardner
: writes:
: >
: >It is irritating, but Kodak ISO ratings on Tmax can't be trusted!
: >
: >What ISO rating do you-all use? 80? 60?? 58 2/3???
Kodak doesn't give ISO ratings for TMAX film at all! Look closely at the
box and you'll see they give an "exposure index", but not an ISO rating.
They have a good reason for this because the film speed is dependent
on the developer used, which can vary widely. Color films have an ISO
rating because they're processed in a standard process such as C-41,
E-6, or K-14.
I rate 35mm TMAX-100 developed in TMAX developer at E.I. 64. YMMV.
--
Jerry Gardner | Maintainer of the Large Format Digest
jgar...@netcom.com | Send subscription requests to jgar...@netcom.com
Ty Monson
Jerry Gardner <jgar...@netcom.com> wrote:
>Kodak doesn't give ISO ratings for TMAX film at all! Look closely at the
>box and you'll see they give an "exposure index", but not an ISO rating.
^^^^^^^^^^^^^^^^^^^
Just to keep the terminology straight, the E.I. *is* an ISO rating.
"Exposure index" has no meaning until given a definition
by a standards organization. ISO is reference to that organization.
The distinction between ISO film speed and ISO E.I. is that the
film speed is prescribed through a standard set of test procedures
to be performed on the film, while Exposure Indices are established
through procedures which would be used for calibrating a meter.
(OK, I don't have a copy of the standards - Is there another organization
that defines exposure indices???)
Guillermo Penate
-> >Kodak doesn't give ISO ratings for TMAX film at all! Look closely at the
-> >box and you'll see they give an "exposure index", but not an ISO rating.
^^^^^^^^^^^^^^^^^^^
Kodak do state in their Tech.Info ISO speed ratings for all of the TMAX
films. They are ISO-100, ISO-400 and ISO-1000 for TMX, TMY AND TMZ
respectively, this ISO speeds are for films processed in TMAX
developers, processing them in other soups may change their ratings
(in particular for TMZ).
-> Just to keep the terminology straight, the E.I. *is* an ISO rating.
-> "Exposure index" has no meaning until given a definition
-> by a standards organization. ISO is reference to that organization.
-> The distinction between ISO film speed and ISO E.I. is that the
-> ..............
IMO, ISO number of a film is the speed determined in a manner published
in ISO standars, is therefore a theoretical (lab conditions) value.
E.I is the actual taking speed for a film by a particular photographer.
This photographer has determined that E.I speed base on his/her
equipment (camera, lenses, etc) and process (try/tank/rotary/etc
processing, temp, chemicals, etc), either by sensitometric testes,
by trial and error, or because a fellow photographer told me.
When ever we set a taking speed for a film on our meter or camera,
that speed is the Exposure Index we are using for that film, that speed
may or may not match the ISO rating for that film.
I entered a little late to this discussion and did not have the chance
of reading the original post, but reading the SUBJECT I think I can see
clearly that the question could very well be: "Kodak suggest a speed of
100 for their TMX film. Is that the speed everybody using?"
In my case, I do use it as a 100, but give between 0 to 2/3 stops more
exposure depending how much detail from the shadow areas I want to
record in the film.
Guillermo Penate
* 1st 2.00b #2045 *
John Sparks
>Subject: Re: Tmax 100 what is REAL ISO
>-> >Kodak doesn't give ISO ratings for TMAX film at all! Look closely at the
>-> >box and you'll see they give an "exposure index", but not an ISO rating.
> ^^^^^^^^^^^^^^^^^^^
>Kodak do state in their Tech.Info ISO speed ratings for all of the TMAX
>films. They are ISO-100, ISO-400 and ISO-1000 for TMX, TMY AND TMZ
>respectively, this ISO speeds are for films processed in TMAX
>developers, processing them in other soups may change their ratings
>(in particular for TMZ).
I've never actually seen the ISO standard for film speeds, but it's
my understanding that the ISO standard specifies a particular "ISO"
developer. It's not TMAX developer or any other commercially available
developer. Tmax developers probably give the closest film speed to
the ISO standard, however (true for just about any film). I'd still
typically rate B&W films about 1/3 to 2/3 stop slower than the ISO
film speed.
John Sparks
Jason Neubert
Both my Prof., and Nick Vertos (spelling?) both told me to
set my camers/light meter to ISO 80. So you might want to
give it a try and see for your self!
Rob Silvers
>Guillermo Penate (guillerm...@canrem.com) wrote:
>>developers, processing them in other soups may change their ratings
>>(in particular for TMZ).
>
>I've never actually seen the ISO standard for film speeds, but it's
>my understanding that the ISO standard specifies a particular "ISO"
>developer. It's not TMAX developer or any other commercially available
>developer. Tmax developers probably give the closest film speed to
>the ISO standard, however (true for just about any film). I'd still
>typically rate B&W films about 1/3 to 2/3 stop slower than the ISO
>film speed.
>
Film has a speed that changes VERY little with different developers or
development times. Developers and development time control contrast.
Even pushing film does not increase its speed much (maybe 1/3 stop).
It raises the highlights so that they make the film a proper density,
but the shadows stay underexposed -- only the speed of the film has a
significant effect on that. I have found TMAX 100 to be ~80 and TMAX 400
to be ~320. TMAX 3200 is ~1000.
--Rob.
Andrew Koenig
> Tmax developers probably give the closest film speed to
> the ISO standard, however (true for just about any film).
The Kodak rep I contacted said that Tmax developer is
recommended primarily for push-processing applications.
For nominal speed ratings, this rep actually recommended
HC-110 instead.
--
--Andrew Koenig
a...@research.att.com
Bascom39
exposures are always a little under as in 1/2 stop . I mean if you really
want to wire it as others have suggested, you test .My experience has been
very consistant with TmX100 . I overexpose a half stop in the studio and
then pull my developer, mabey 30 seconds,this yields good results for me
when I,m doing head shots but I've noticed out in daylight it always seem
to be a100 asa film. By the by I use D76 replenished in 35 mm and 120
Bascom39......Waldo Bascom Photography.....San Rafael Ca