Developer from Green Tea

[Alan Johnson]

Green tea was heated in sodium hydroxide solution (Care,serious hazard) for 5min 100C.
After filtering and cooling, phenidone was added.

Green T-1
Green Tea...........................25g
Sodium Hydroxide...................5g
Phenidone............................0.2g
Water to...............................1L

APX 100 was developed 30m 20C, ag 10s/min.

A blank solution of identical composition but without the green tea was prepared and APX 100 developed as before.

Green T-1 gave negatives of slightly low density (2 are attached).
Blank solution gave negatives of very low density showing the green tea activated the phenidone.

Some negatives from Green T-1 were bleached in 100g/L ferricyanide/bromide ,fixed and washed.They showed a faint relief image tanned into the gelatin.Green T-1 is unpleasant to use,it left a grey deposit on the tank and reels.

The results are similar to those I obtained from red grape juice developer (posted here).In hot alkaline solutions the green tea catechins probably break down to gallocatechin gallate.
http://en.wikipedia.org/wiki/Gallocatechin_gallate
It seems that,after 2 similar tests, if a plant provides a developing agent and it is not ascorbate (Broccoli-posted here) or sugar,
that developing agent is likely to be formed from units of 6 linked carbon atoms with OH group(s) attached and to be superadditive with phenidone and tan gelatin.
There may be better ways of extracting the developing agent than heating in alkaline solution.

 

[albada]

Those pictures are beautiful. I'd say they are worth the unpleasantness of cleaning the tank/reels.

Mark Overton

 

[Alan Johnson]

Now I am making a tincture of 100g green tea in 1L vodka to see if it is still a good developer and any cleaner, with the same phenidone and sodium hydroxide added after 3 weeks when it is ready.
I will tack the results on here.They use tinctures in herbal medicine, I dont know why.

 

[Gerald C Koch]

Interesting For those that like their tea sweet, Glafkides mentions how to make a developing agent from glucose near the end of Chapter IX. A bit of lemon juice for the ascorbic acid. I can't resist asking is this liptonol?

 

[pgomena]

Liptonol. I love it.

My son came out of a local fancy grocery store with a tiny paper cup of green tea with rice water or some such. It tasted pretty much like what I'd expect summer swamp water to taste. I now have no doubt green tea will make a fine developer. And drink. For someone else.

Peter Gomena

 

[subsole]

That's why they call it "Earl Grey"!!

 

[DarkroomExperimente]

you can also get green tea extract at a pharmacy/grocery store...that's what I used....

very interesting

 

[DarkroomExperimente]

Alan, how did you arrive at the 0.2 gram amount of phenidone?

I want to start mixing some of my concoctions with phenidone and run similar tests on them

 

[Alan Johnson]

DE,

Thanks for the tip about tea extract being available in some grocery stores.

I use 0.2g/L phenidone because it is about the minimum can be weighed with reasonable accuracy. I weigh out 0.4g ,cut it in two and use half (actually this is scaled down to only make enough to fill a vodka bottle, not 1L).
It seems to be OK in that with sodium hydroxide and water alone it gives only minimal density images after 30m 20C development and it's easy to see the superadditive effect of adding the tea.

 

[Gerald C Koch]

There are a number of chemicals found in unusual situtations that are capable of developing a silver image. The human body makes a class of chemicals called catecholamines. One of these, the hormone adrenaline, is such a developing agent.

 

[DarkroomExperimente]

I have found many extracts in grocery stores that I have used to developed film - I went to Whole foods and found a wealth of things to play with...I have since found a great pharmacy not too far from me that has a zillion products like the tryptophan I tested recently...their website is http://www.the-apothecary.com/

 

[wildbillbugman]

My experience with "natural" substances used in photography is using chlorophill, extracted from spinache leaves coachanilla beatle extract as red and green sensitizing dyes for making homemade panchromatic silver-halide emulsions. They actualy work! Although commercialy availible dyes work better, with much less messy trouble. But I am glad when I see people working on photochemistry using edible substances. Especialy the vodka.
Bill

 

[Gerald C Koch]

A lot of unneeded experimentation can be eliminated by using the Kendall-Peltz rule. The rule allows one to determine whether a chemical is a developing agent from its structure. For example, catechol (1,2 dihydroxybenzene) and hydroquinone (1,4-dihydroxybenzene) are developing agents while resorcinol (1,3-dihydroxybenzene) is not.

 

[Alan Johnson]

Vodka tincture gave better results.
I did not detect any deposit on the reels.
Bromide was added,this reduced but did not eliminate fog.
Vodka Tincture:
Green Tea.....................100g
Vodka.............................1L
This was kept in a sealed bottle at around 70F for 3 weeks and shaken daily.After 3 weeks the tea was filtered off through cotton wool,3 times to get it nearly clear, and the made up to 1L with water ("Tincture").
The pH was 6.0 +/- 0.1
From the data below 1L Tincture contains 30g phenolics.
http://www.coffee-tea.co.uk/Green-tea-composition.php

Green T-2
Tincture 100ml....................3g Phenolics
Phenidone...........................0.1g
Potassium Bromide................0.5g
Sodium Carbonate anh.............5g
Water to...............................1L

APX 100 was semi-stand developed in Green T-2 60min 25C agitate 20s every 10 min.
The negatives looked like Pyrocat-HD negatives,having a slight brownish general stain, a relief image caused by tanning and an apparent compression of tones.
However,the Green T-2 negatives showed more fog and appeared to have larger grain and lower acutance,though not to the point of being unuseable.

It is quite interesting from a chemical point of view that the green tea catechins regenerate the phenidone and and are probably converted to quinoids which tan the gelatin, although Pyrocat HD is better in all respects for negative quality.The attached pic was developed in Green T-2.

 

[Kamar Kamera]

How about if caffenol to be teanol...
Coffee replace to tea?
So the ingredients : Green tea, Vit. C, and Sodium Carbonate (soda ash).
Anyone have tried?

 

[Alan Johnson]

Search this groups discussions for green tea:
http://www.flickr.com/groups/33051635@N00/
It gives some results.

 

[Tom1956]

Oh, puleeez... not another commercial for green tea. Two years ago I never heard of it. Now green tea is the magic chemical that is saving the world.

 

[Gerald C Koch]

Green tea, phooie. I think grass clippings from my front lawn would have more flavor.

 

[250swb]

One (1) litre of vodka!

I think I'd need to drink that to get to the point where I thought green tea was a great developer.

Steve

 

[Gerald C Koch]

The reason that green tea, coffee, and other botanicals work as developers is because they contain various derivatives of catechol. These compounds are wide spread throughout the plant kingdom. In coffee this compound is caffeic acid. The human body also makes several catechol derivatives called catecholamines such as dopamine, ephedrine, and epinephrin. This fact probably explains why human urine can be used as a developer.