D-76 vs ID-11 Aging test . Part II

[ramiro_aceves]

Hello B&W fans.

 

As I promised you, I present the ID11 and D76 aging tests PART II.

Sorry for the delay but I had little free time for experimenting, and

the more the time, the better for the test. An error in one of the

tests, delayed the tests even more. I use a radio controlled clock

for measuring time, reseting it for the tests so that it starts from

0 hours. Unfortunately, the clock adjusted its time automaticaly via

radio during the first test, invalidating the test :-(

 

Introduction: As published before here, I experienced disapointing

results when I encountered big activity increase in ID11 developer

when stored for one month in PLASTIC bottles and TAP WATER. The

increasing activity was shown as early as 15 days from the developer

mixing. So I wanted to know the reason of that, was the water? the

bottle? the developer?

 

 

Test procedure: I mixed 1 liter of D-76 and 1 liter ID-11 with

DISTILLED WATER so that I filled 2 beer GLASS bottles and 2 PLASTIC

bottles for each developer.(Bottles were 250 cm3 each). Beer Glass

bottles were closed with corks.

 

I used inmediately one plastic bottles for each developer for the

first test at 1:1 dilution. That was published one 2 months ago here,

so the developer was fresh.

 

Now I have repeated the tests 2 months later using the GLASS bottles.

As you can see in the graphs, the activity of both developers has

slightly DECREASED, both in the same extent. Again, ID11 seems to

develop to a slightly higher contrast than D76.

 

Conclusion of PART II test:

 

Two months later, with Glass bottles and Distilled water, the

increase of activity has no longer appeared. Indeed, a slightly

DECREASE in activity is noticeable. Both developers were CLEAR. When

I had the problems before, developer was slightly yellow.

 

The strong activity Increase noted before, could be caused by two

factors:

 

-The plastic bottles.(I personaly doubt that)

-The Tap water. I think strongly that tap water at home can

affect developer. Indeed, my tap water smells and tastes very bad,

like swimmingpool water :-)

 

Another conclusion is that ID-11 appears a bit stronger than D76, so

development times should not be the same for both developers.

 

 

The PART III of these test will be with the PLASTIC bottles. If

contrast rises with that bottles, it means that the plastic is the

culprit. If contrast mantains unaltered, the culprit is the water.

 

I hope to finish the tests in the following days.

 

I hope you liked this test, and you can extract your own conclusions.

I will appreciate you comments.

 

See you soon.

 

Ramiro.

[photojim]

A most interesting test. I think one could attribute the very slight difference in performance between the two chemicals to sample variation. You should test 99 other packages of each developer to see if the results are consistent. :)

 

Have you ever mixed your own chemicals? I'd be very interested to know how homemade D-76 compares to these two.

[jorge_oliveira2]

Ramiro

 

One interesting aspect of your test is that there was a decrease in activity for both developers.

 

It's a quite well documented fact that the original (circa 1920) D-76 would INCREASE activity in about two months, so Kodak made changes to the original formula buffering it with boric acid so this would not happen.

 

Now, it is believed that ID-11 is still the original formula. Your tests indicate this is not true.

 

 

 

Your tests