E-6 Chromebrew

For quite a long time now I’m trying to develop my own E-6 Formular, inspired by the “Watkins factor Cromebrew”

First developer
Sodium hexametaphosphate (Calgon) 2.0 g
Sodium sulphite, anhydrous 39.0 g
Potassium carbonate, anhydrous 14.0 g
Sodium bicarbonate 12.0 g
Phenidone 0.6 g
Hydroquinone 6.0 g
Sodium bromide 2.2 g
Sodium thiocyanate 1.0 g
Sodium hydroxide 3.3 g
Potassium iodide, 0.1 per cent solution 4.5 ml
Water to 1.0 litre
1.0 litre


Colour developer
Sodium hexametaphosphate (Calgon) 2.0 g
Trisodium phosphate crystals 36.0 g
Sodium hydroxide 3.0 g
Sodium sulphite, anhydrous 4.5 g
Sodium bromide 0.65 g
Potassium iodide 0.1 per cent solution 30 ml
Sodium thiocyanate 1.3 g
Citrazinic acid 1.25 g
CD3 11.0 g
Water to 1.0 litre

Look for the entire article at http://opie.net/orphy/photo/dr/wkft-e6.html


This receipt is a good starting point, but far from being perfect. The FD is “to hot”, does include to much sulphite and is (as all hydroquinone developers) not as stable as whished.
The CD pH is to high (too much Sodium hydroxide) which leads to severe color shifts. The resulting slides where quite “thin” as well because there is nearly the double amount Citrazinic Acid used as needed. A minor mismatch is the iodide potion.

I’ve done a lot of investigations and experiments concerning the ratio of CD3, CZA, sulphite, bromide, iodide and pH in the color developer. Most values are not common, except sulphite Kodak claims 5,5g/ltr. In it’s Z6 manual.

Same misery for the FD, only the bromide potion is told in Z6 and stated to 2,57g/Ltr.
Well, well there is a lot of room for speculations and only very few fixed points. So I’ve shot literally hundreds of Grey cards, always on the hood for Information that makes sense.

1. It’s a good idea to replace the hydroquinone against hydroquinone-monosulphate potassium salt. It’s activity stays constant.
2. The afforded Dimezone S is not available for me, I’m still using Phenidone (A), it’s aging is less dramatic as the hydroquinone’s
3. Watch for the pH, it should be around 9,6
4. Bromide potion is given
5. Sulphite has to be reduced for solve less silver, maybe reduce thiocyanate to 0,8g/L as well

6. Where are all my sheets??
7. Reduce the amount of Citrazinic acid to something about 0,6g/Ltr
8. The CD is VERY pH dependent, the given amount leads to a greenish slide, I’ve tried to come to pH 11,9 and added 19 ml of a 10% NaOH soloution
9. Reduce bromide to 5,5g/Ltr. as stated
10. Are there still questions, YES there are! What about Iodide and the infamous “inter image effect” ? look for
http://www.city-net.com/~fodder/hand/colorrev.html
this is a salvific Information !! Yellow-blue axis can be controlled with Iodide, as well as magenta – green axis is given by pH.


“ A very small quantity of potassium iodide is often included in the formulation to act as a restrainer, having greater effect on the top blue sensitive layer than on the other two layers. This means that the yellow dye content of the film can be controlled quite accurately by varying the iodide content (always assuming, of course, that you are mixing your own solutions from raw chemicals).”


RECEIPT I , base reciept
First Developer:
Tab Water ………………………...…….750 ml
Calgon………………………………………….. 2.0 g
Sodium sulphite, anhydrous ……………………28 g
Potassium carbonate, anhydrous ……………….14.0 g
Sodium bicarbonate …………………………… 12.0 g
Phenidone …………………………………….... 0.5 g (solve it in 10 ml of warm glycol)
Hydroquinonemonosulphate ……………………22 g (works well, perhaps less is possible)
Sodium bromide …………………………………2.6 g
Sodium thiocyanate………………………..…… 1.0 g
Sodium hydroxide 10% solution……………...25ml
Potassium iodide, 0.1 per cent solution ………. 4.5 ml
Water to 1.0 litre
pH 9,6


Color Developer:
Aqua demin……………………………...750ml
Calgon………………………………………2.0 g (not really necessary)
Trisodium phosphate crystals ……………. 36.0 g
Sodium hydroxide 10% solution ………..19 ml (!!)
Sodium sulphite, anhydrous …………….. 5.5 g
Sodium bromide ………………………….0.55 g
Potassium iodide 0.1 per cent solution ……40 ml (36 -37,5 seems to be optimal)
Sodium thiocyanate…………………………1.0 g
Citrazinic acid ………………………………0.6 g (!!)
CD3 ……………………………………… 10.5 g
Water to 1 litre
pH 11,9-12,1





Why do I work on this stuff?? I had a bunch of films showing me a severe magenta /magenta-Blue color cast, very bad… It seemd to be preaged, overheated, bad stored or whatever. It’s a kind of reversal engineering, the opposite of disposal…

To use this film I increased the pH of the CD as stated in the Jobo E-6 handbook, adding NAOH solution 10%. 4 ml/250/ml CD was to less, 6,5ml/250ml CD was too much The optimum additional amount was 5ml/250 ml (20ml/Ltr.) of the CD. The Red-Blue balance was neutral now.
There was still a slight blue cast. For solving that I added 2 later 3 mg potassiumiodide to the FD (+3mg /Ltr. was right)

That gave me following composition:

RECEIPT II

First Developer: for aged film (my Agfa's)
Tab Water ………………………...…….750 ml
Calgon………………………………………….. 2.0 g
Sodium sulphite, anhydrous ……………………28 g
Potassium carbonate, anhydrous ……………….14.0 g
Sodium bicarbonate …………………………… 12.0 g
Phenidone …………………………………….... 0.5 g (solve it in 10 ml of warm glycol)
Hydroquinonemonosulphate ……………………22 g
Sodium bromide …………………………………2.6 g
Sodium thiocyanate………………………..…… 1.0 g
Sodium hydroxide 10% solution……………...25ml
Potassium iodide, 0.1 per cent solution ………. 7.5 ml (Changed)
Water to 1.0 litre
pH 9,6



Color Developer:for aged film (my Agfa's)
Aqua demin……………………………...750ml
Calgon………………………………………2.0 g
Trisodium phosphate crystals ……………. 36.0 g
Sodium hydroxide 10% solution ………..49 ml (Changed)
Sodium sulphite, anhydrous …………….. 5.5 g
Sodium bromide ………………………….0.55 g
Potassium iodide 0.1 per cent solution ……36ml (Changed)
Sodium thiocyanate…………………………1.0 g
Citrazinic acid ………………………………0.6 g
CD3 ……………………………………… 10.5 g
Water to 1 litre
pH haven’t measured approx.12,5


Procedere:
Temp 38°C
Rotation, Speed 4 (Jobo CPP)

Temperated prewash 2 x 1 min ( this is important, I'v made bad experiencies with insufficient dry prewarm steps)

FD 6:45 min
Stop 1min
Rinse 4 min

Reversal exposure 2 x 2 min (1000 Watt Bulb)

Prewash 1 min
CD 5:00
Stop 1:00
Rinse 3 min
Bleach 8 min
Fix1 3min
Fix2 3 min
Final wash 10 min

Stabi 1 min


Here a lousy scan:

[IMG][/IMG]


First line : left Tetenal 3 bath , next added 6.5 ml Naoh sol.10%/250 ml to CD (reciept I), overcorrection leads to green shift
Second line : added 4 ml Naoh 10%/250ml CD (reciep I) still slight magenta cast. Next greyscale
Line 3 till 7
added 3 mg Kj to FD/ltr., added 5 ml Naoh 10%/250ml to CD (recieptI). This is reciept II, doesnt it look pretty ??


Measurements

Film Agfa precisa 100 @ 80Asa
Jobo test chart
Macbeth TR 527 “normal” Filter (Tolerance ?)

FD 6:45 min
CD 5:00 min.
.............|...R...|...G..|....B...|..R-G..|..B-G..
---------+-----+-----+------+------+-----+
Feld 3 ...|1,16..|1,11..|0,91..|0,05...|-0,2
---------+-----+-----+------+------+-----+
Feld 5 ...| 1,54 |1,51..|1,29..|0,03 ..|-0,22
---------+-----+-----+------+------+-----+
Dmax.....| 2,87 | 2,92 |2,82 |

Dmin 0,3 (through acetat sleeve)

Blue seems still ab bit underrepresented, but I do believe my eyes, the slides look very nice. Anyway the densitometer's filters mismatch and seems to be quite old... The Dmax is still a bit low, but acceptable for this film. It would be worth a try without citrazinic acid. Maybe bonzoetriazole in the FD is an option.





That’s not all, I’ve tested the Receipt I , my Base for modifications, on two up to date Kodak slide films (unmodified).

Anyway, this was all intended to develop aged film as well as possible. A cross check with Receipt No.I and fresh film showed very good potential, I'll try to show a scan, but be warned this is only a old flatbed scanner with deactivated light and a small light box to make it a cheap through light unit. Bad quality, but Trends are noticeabily..

[IMG][/IMG
1.Line Aged Agfa Film developed with Tetenal 3 bath Kit
2.Line Aged Agfa Film developed with my homebrew II (recieptII)
3.Line Greyscale
4.Line Kodak EPR64 developed in homebrew I (Base reciept, reciept I)
5.Line Kodak EPR64 developed in Tetenal (different light condition)
6.Line Kodak elitechrome 100 in homebrew I (Base reciept, reciept I)

The EPR64 and the Elitechrome 100, the both came out pretty well, The EPR64 is nearly perfect,just some fine tuning will left necessary. The Elitechrome100 seems to be quite warm and does have an increased contrast, but this seems to be normal for a “consumer film”.


Would be glad to hear some comments and suggestions !
Regards,
Stefan