Absolutely! Both fixer and developer must be agitated
properly. Fixing time is decreased with agitation and is
probably minimum with constant agitation. Development rate
increases with agitation but continuous agitation is not
necessary to get good results provided there is sufficient
agitation. I think one reason people have problems with
development is incorrect or absent agitation.
  I have no idea what method Kodak uses for finding film
curves. The technique for measuring speed using the ISO
method is specified in the standard but may not be the same
as used for developing sensitometric tests.
 Dip and dunk machines are typically used for
photofinishing. Again, I have no idea what Kodak used for
its sensitometric testing.
 Fixing rate has been very extensively researched and there
is a ton of stuff in the literature about it. For films like
T-Max and Tri-X, which have lots of Silver Iodide in the
emulsion, Ammonium thiosulfate fixers ("rapid" fixers) have
an advantage in speed and completeness of fixing. Iodide
acts as a restrainer of fixing. Bromide does also but to
such a small degree that it is not significant. A good test
is to measure the clearing time of a film. This is the time
it takes undeveloped but wet film to become visually clear
in the fixing bath. The reason for using wetted film (soak
for two or three minutes in water) is that fixing rate and
the effect of the concentration of thiosulfate in the fixer,
changes with wet vs: dry film. The fixing rate of dry film
is misleading. The clearing time is an indicator of how well
the fixer is working with the specific film. Total fixing
time is, by old rule of thumb, double the clearing time.
There is also an old rule that the fixing bath should be
discarded when clearing time doubles from that of fresh
fixer. At least for a single bath, and probably even for two
bath fixing, this is too far exhausted for archival
processing and may indicate that the fixing process is not
being completed.
  It should be understood that clear film may still have
enough unfixed halide or insoluble fixer reaction products
in it to cause image degradation with time. The real test of
completeness of fixing is to use a test solution which will
convert any residual silver into a visible form. The usual
tests are a solution of Sodium Sulfide (not sulfite) or a
1:9 dilution of Kodak Rapid Selenium Toner. Both the sulfide
and the selenium will tone halide as readily as metallic
silver so they leave a brown or yellow stain if there is
much residual silver in the emulsion. The Selenium test must
be used on well washed material because it fails if too much
hypo is left in the emulsion. This is too bad because it is
longer lasting than the sulfide solution and free from the
rotten egg odor of sulfide.
   The sulfide test is:

Kodak ST-1 Residual Silver Test Stock Solution
Water                         100.0 ml
Sodium Sulfide, anhydrous       2.0 grams

For use dilute 1 part stock with 9 parts water.

Place a couple of drops on a clear area of the print or
film, which should be wet but blotted free of surface water.
Allow to stand for 2 to 3 minutes and blot off. There
should be no visible stain.

If it is desired to use the print or negative it should be
washed following the test. If not washed the test area will
develop a stain with time.

 This is a better test than the Iodide test for fixing
baths because it is a direct test of fixer effectiveness.
For prints its best to fix and wash a scrap of paper for the
purposes of testing rather than using the border of an
actual print since the scrap can be tossed away after the
test is completed.

  I would like to find out from Kodak how they go about
sensitometric testing. I will try to write to my contact
there but the customer service people are pretty isolated
from whatever laboratory people are still there.
  BTW, I have always gotten good results from T-Max films
but they very certainly are more sensitive to variations in
development than other films. To get predictable contrast
one must be careful of temperature and time and consistent
in agitation. T-Max is capable of very high densities so
over exposed or over developed negatives can be extremely
difficult to print.

...

may1005 from Lloyd Erlick,

Pink Skunk:

Three ounces Tequila
One ounce exhausted fixer
Garnish with strip of inadequately fixed 35mm film

regards,
--le

    Ah ! This explains Sylvias inaccuracies with Xtol !

JD