complete failure with e76

RalphLambrecht

Subscriber
Joined
Sep 19, 2003
Messages
14,657
Location
K,Germany
Format
Medium Format
i converted the id11d76 formula into a pc formula by replacing m with p and q with c, but after2 ok films and black test leadsrs,i got no more develop,ent ay all.the films are totally blank:nothing. i know, i did not account for any change in super additivity, but how can i fix ths
 

Keith Tapscott.

Member
Joined
Jun 11, 2005
Messages
1,807
Location
Plymouth. UK
Format
Multi Format
Ralph, why have you done this? Ascorbic acid devs are notorious for short life and Patrick Gainer's PC-TEA and perhaps Ryuji Suzuki's formulas are about the only stable Vit-C derivative developers I can think of.
Stick with plain D-76/ID-11 or try something more exotic like Pyrocat-HD.
 

Neal

Subscriber
Joined
Dec 3, 2004
Messages
2,020
Location
Chicago, West Suburbs
Format
Multi Format
Hi Ralph,

Why not compare the D76 formula with those of Patrick Gainer? As I recall, he used a high ration of C to P and using it as the "B" developer component and the preservative at the same time. I never tried it.

Neal Wydra
 

albada

Subscriber
Joined
Apr 10, 2008
Messages
2,175
Location
Escondido, C
Format
35mm RF
Keith Tapscott. said:
Ascorbic acid devs are notorious for short life <snip>
Click to expand...

Indeed. The problem is called the "Fenton reaction" wherein trace amounts of iron in the developer destroy all the ascorbate. The only work-arounds I know of are (1) use Kodak XTOL, or (2) use home-brews as one-shot. Personally, I wouldn't trust a home-brew PC working solution that's over a couple of hours old unless it has an iron-chelator in it.

Mark Overton
 

Gerald C Koch

Member
Joined
Jul 12, 2010
Messages
8,131
Location
Southern USA
Format
Multi Format
Ascorbic acid developers are stable if a chelating agent is used to inactivate any Iron (III). It has been my experience that the Ryuji formula works quite well.
 

eclarke

Member
Joined
Jun 11, 2004
Messages
1,950
Location
New Berlin,
Format
ULarge Format
Or give this a try..

Germain's Finegrain *
makes 1L*

750 cc. Water*
7 g. Metol*
70 g. Sodium Sulfite*
7 g. Paraphenylenediamine*
7 g. Glycin*
Water to make 1L*

Use full strength


This may start a chorus of replies making comparisons to Edwal 12. I have developed around 3000 sheets in this stuff now and it's my first choice with tri x, tmx, tmy, hp5, efke ir and anything else I can throw at it..Cheers, Ec
 

Gerald C Koch

Member
Joined
Jul 12, 2010
Messages
8,131
Location
Southern USA
Format
Multi Format
The iron contamination usually comes not from the water used but from the chemicals like sodium sulfite used in the formula. DS-10 uses salicylic acid and TEA and these are probably the easiest to obtain. You can't use just any chelating agent as some like EDTA encourage the Fenton reaction. For 1 liter of solution use 1g of salicylic acid plus 10 ml of TEA. Salicylic acid can be obtained from most compounding pharmacies. It is not expensive.
 

albada

Subscriber
Joined
Apr 10, 2008
Messages
2,175
Location
Escondido, C
Format
35mm RF
RalphLambrecht said:
i think, that's it .the heating rod in y kettle is of copper. can you suggest a chelating compound and a quantity?
Click to expand...

Iron, not copper, is apparently what kills ascorbate developers. There are some iron impurities in your chemicals which could be causing your problem.
Anyway, Dequest 2010 (similar to Etidronic acid) is reported to be a good iron-chelator. Try 1 gram/litre. Note that I haven't tried this myself.

Mark Overton
 

Gerald C Koch

Member
Joined
Jul 12, 2010
Messages
8,131
Location
Southern USA
Format
Multi Format
Copper can also catalyse the Fenton reaction. This why two chelating agents are used in DS-10..
 
You must log in or register to reply here.
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…