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Old Dektol



 
 
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  #1  
Old February 21st 04, 03:06 AM
10x@_telus.net
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Default Old Dektol

I just set up a temporary darkroom.
Boy, ho, boy ,oh boy is the Thomas sodium safelight nice to work with.
As is the forty year old Beseler 23C.

I found some dektol stock that I had mixed over four years ago with
the intention of developing some prints and stored in a mylar wine
bag. It had just a bit of discoloration so I mixed it 1:1 and tried it
out. I got black blacks and white whites, no "muddy" prints and the
image came out in about fifteen to twenty seconds. Three hours and
twenty prints in the tray and it was starting to discolour (turn a bit
brownish)

One of the reasons I stopped darkroom activity was the resin coated
paper that came out. It seemed to give slick and plastic looking
prints. The AGFA resin paper I used today gave very nice prints.
I'm going to mix up a new batch of dektol and see how much nicer the
prints do get.

The Tmax 400 I develped in 1:1 D76 gave a really nice negative to
work with. I did over develop the film by about 5%
It is a good start.

It seems there have been some very nice advances in the B&W field
since the 70's
I hope there will be more spare time in the near future so I can play
more.

My 20 year old son is really impressed with the 7 x 10 glossies, I
will have to wait a few days to see if I like any of them...
  #3  
Old February 22nd 04, 02:10 AM
Richard Knoppow
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Posts: n/a
Default Old Dektol


wrote in message
...
I just set up a temporary darkroom.
Boy, ho, boy ,oh boy is the Thomas sodium safelight nice

to work with.
As is the forty year old Beseler 23C.

I found some dektol stock that I had mixed over four years

ago with
the intention of developing some prints and stored in a

mylar wine
bag. It had just a bit of discoloration so I mixed it 1:1

and tried it
out. I got black blacks and white whites, no "muddy"

prints and the
image came out in about fifteen to twenty seconds.

Three hours and
twenty prints in the tray and it was starting to discolour

(turn a bit
brownish)

One of the reasons I stopped darkroom activity was the

resin coated
paper that came out. It seemed to give slick and plastic

looking
prints. The AGFA resin paper I used today gave very nice

prints.
I'm going to mix up a new batch of dektol and see how

much nicer the
prints do get.

The Tmax 400 I develped in 1:1 D76 gave a really nice

negative to
work with. I did over develop the film by about 5%
It is a good start.

It seems there have been some very nice advances in the

B&W field
since the 70's
I hope there will be more spare time in the near future so

I can play
more.

My 20 year old son is really impressed with the 7 x 10

glossies, I
will have to wait a few days to see if I like any of

them...

Pretty amazing. I've never stored a filled bottle of
Dektol for very long. A partially filled bottle may last for
six months but will start to get quite brown after that.
Dektol is slightly straw colored when freshly mixed. Kodak's
figures on lifetime of chemicals is quite conservative. They
give worst case numbers to insure the products will work
satisfactorilly. BTW, really badly oxidized Dektol will be
black and smell like spoiled fish due to the hydroquinone.


--
---
Richard Knoppow
Los Angeles, CA, USA



  #4  
Old February 22nd 04, 03:32 AM
10x@_telus.net
external usenet poster
 
Posts: n/a
Default Old Dektol

On Sun, 22 Feb 2004 01:10:48 GMT, "Richard Knoppow"
wrote:


Pretty amazing. I've never stored a filled bottle of
Dektol for very long. A partially filled bottle may last for
six months but will start to get quite brown after that.
Dektol is slightly straw colored when freshly mixed. Kodak's
figures on lifetime of chemicals is quite conservative. They
give worst case numbers to insure the products will work
satisfactorilly. BTW, really badly oxidized Dektol will be
black and smell like spoiled fish due to the hydroquinone.


This stuff came out of the mylar bag straw coloured. I wanted to see
if it would still work before I mixed a new batch.
I did about 30 8x10 prints on one tray of dektol mixed 1:1
The last two prints came out "muddy", there was also a brown
perciptate on the bottom of the tray at the end of the session.
I do suspect this stuff was dying in the tray.
  #5  
Old February 22nd 04, 08:58 AM
Richard Knoppow
external usenet poster
 
Posts: n/a
Default Old Dektol

wrote in message . ..
On Sun, 22 Feb 2004 01:10:48 GMT, "Richard Knoppow"
wrote:


Pretty amazing. I've never stored a filled bottle of
Dektol for very long. A partially filled bottle may last for
six months but will start to get quite brown after that.
Dektol is slightly straw colored when freshly mixed. Kodak's
figures on lifetime of chemicals is quite conservative. They
give worst case numbers to insure the products will work
satisfactorilly. BTW, really badly oxidized Dektol will be
black and smell like spoiled fish due to the hydroquinone.


This stuff came out of the mylar bag straw coloured. I wanted to see
if it would still work before I mixed a new batch.
I did about 30 8x10 prints on one tray of dektol mixed 1:1
The last two prints came out "muddy", there was also a brown
perciptate on the bottom of the tray at the end of the session.
I do suspect this stuff was dying in the tray.



The mixed developer is slightly yellow as mentioned above but the
powder should be pure white. Any indication of a yellow or brown color
is a sign the developing agents have begun to oxidize. Since this
shows that the bag is leaking other components which can be oxidized
will also be. This is mostly the Sodium Sulfite. Sulfite performs
several functions in developers but one of them is to protect the
developing agents by preferentially absorbing oxygen. The sulfite is
oxidized to sulfate. Sulfate is white but doesn't absorb oxygen since
its already oxidized. Metol and Hyroquinone both generate a yellow dye
as they oxidize. When badly oxidized Dektol looks like coffee grounds
and smells awful, probably from the Hydroquinone. I've opened a couple
of bags of Dektol that looked like this. Bought very cheap at a camera
sale, they were no bargain. I tried mixing one out of curiousity. The
resulting liquid was also nearly black. I tried a bit of fogged paper
in it, it simply stained the paper. Old devloper in sealed cans is
probably OK. These cans were hermitically sealed. The bags are made of
a layered combination of paper and metalized plastic. For some reason
they tend to become leaky and don't usually have a very long shelf
life. Kodak has recently changed its packaging to a metalized plastic
which is seamed on only one side and should be more reliable. IMHO
nothing will ever match the old tin cans.:-)

Richard Knoppow
Los Angeles, CA, USA

 




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