Saturday, February 18, 2012


I went ahead and developed a film in a "tea" made from boiling crushed corn-cobs.

But waitaminute! What is that?

Corn-cobs has many uses, for this purpose its sold by a company called Midway in USA and used for polishing fired gun cartridge cases, to get rid of powder dirt and grime.

This stuff is crushed and graded through industrial sieves and has a grainy structure.

I measured out 50 gram and boiled for 20 -30 minutes in one litre of water.

The resulting "tea" was hydrolysed with 50 gram washing soda, and 15 gram ascorbic acid powder was added as soon as all the soda had disolved.

A clip test indicated that the mixture was a little less than half as active as Liptonol, a developer based on tea from ordinary household tea....

Time in the bath was therefore 40 minutes, followed by ordinary fix and wash.

Negatives are hung to dry, looks a bit less contrasty than Liptonol, maybe on par with Caffenol, but less active than the coffee recipe.

Anxious to see if grain is better or worse than Liptonol.......

Looking forward to scan as soon as the film is dry.

Recipe :

1 litre "tea" from boiling crushed corncobs for 30 minutes.

Water 1 litre
Corncobs, crushed 50 gram
Washing Soda anhydrous 50 gram
ascorbic acid poder 15 gram

Boil the corn for 30 minutes, strain through inert sieve, set to cool.....
Add 50 gram of soda, the color changes and bobbles appear on surface, klet sit for a while...
Add 15 gram of ascorbic acid powder this will really produce bubbles but it subsides quickly, let sit.....

Developing :

Develop for 45 minutes at 20 degrees centigrade, expect low contrast negatives well suited to scanning.

Example :

First test negatives was a film with exposure triplets, 1 at box speed, 2 at -1 stop, 3rd at +1 stop
Developed for 40 minutes, indicated by a clip test that took quite a while longer than expected.

For a first test the result was less than spectacular the negatives show thin, flat negatives with every indication of a slight underdevelopment and underexposure the +1 negatives are best across the board.

This is a triplet :

This triplet is from left to right : 1 Box speed, 2 -1 stop, 3 +1 stop
This image is not altered from scanning.

Here the triplet has been altered by just take a chance, 1-click in Picasa

And this is the +1 ISO negative untouched

And further, this is the +1 negative with the contrast and saturation slightly altered/upped
by just one click on the same 1-click button in Picasa

AS far as I'm concerned this is not a success, but it indicates a roadmap to further tests & improvement

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