Blank Colour Films

Hi guys,

I just tried to develop 2 colour films with my Tetenal C41 kit, but got 2 totally blank transparent rolls. Could anyone suggest what might have wrong here? This is the first time this has happened, and I used this batch of chemicals successfully a couple of months ago.

Things to note:

1) The CD was very dark when it went in (like coffee)

2) I've been using Tetenal Protectan spray before storing the chemicals, surely this couldn't have ruined them??

3) I'm 99% sure I didn't mix up the CD and BLIX .... but the frame numbers aren't visible

Thanks in advance. I'm stumped!

The light sensitive goodies we use are salts of silver. These are comprised of silver and a halogen (Swedish for salt maker). The developing agents we use are able to identify exposed silver salt crystals and then reduce them to their two components which are metallic silver and a halogen. The metallic silver forms a black & white image. The halogen component is dissolved away by the waters of the developer solution. The newly formed metallic silver is attached by oxygen dissolved in the waters of the developer.

Also in the film emulsion is incomplete dye in the form of oily globules. These dyes are colorless or nearly so; as such they are said to be in a leuco state (Greek for white). The oxidizing metallic silver acts as a catalyst causing adjacent leuco dye globules to switch state and blossom into a full blown dye that will comprise the color image.

The before-mentioned developing agents have an affinity for oxygen. They are closely related to benzene initially derived from coal. These oxidize over time and revert back to coal tar. Thus the blackened developer solution is comprised of spent developing agents.

You say the film is blank! This can be result of spent developer or film that was never exposed, or perhaps some other processing mishap. Look at the edges of your film. If you see viable edge printing, the developing steps were likely OK .

You say the film is blank! This can be result of spent developer or film that was never exposed, or perhaps some other processing mishap. Look at the edges of your film. If you see viable edge printing, the developing steps were likely OK .

The OP already answered this. There are no edge markings. So, this is a processing problem and the most likely issues would seem to be depleted or improperly mixed developer or mixing up the CD and blix.

1) The CD was very dark when it went in (like coffee)

There's your answer!

Fresh colour developer should be a pale straw colour, and no darker than an IPA beer.

If it's the colour of coffee it's oxidised and useless.

Full to the brim brown glass bottles with a good airtight stopper are the only way to store it. Even then, two months is pushing it for storage when it's part used.

I'm pretty sure the instructions that come with the kit give good guidelines on how long it can be stored. Ignore those instructions at your own risk.

It really came out clear, not orange?

The colored couplers should still be in the film, even if you put in fixer or blix first.

But yes, dark color is not good for developer, but it does have a little color.

Blix tends to be a dark red color, though.

That happed to me when I accidentally processed B&W film in C41.

I guess when there is no dye and you bleach away all the silver, there isn't really anything left. :)

The developer must have really been in bad shape if you got nothing at all. When testing cameras I'll often use expired film and/or aging chemicals. I've gone well past the recommended 6 months and 8 rolls with a single batch of C41. I've used dark-ish developer but nothing nearly as opaque as coffee.

I'm sure in my case some of the resulting images have been somewhat degraded with the old chemicals but nothing so bad that I threw the whole lot out.

But I do use collapsible bottles and store them "full" out of the light.

Are we talking 'Cafe au lait' here ? If it is as opaque as that, maybe the dev has been contaminated with some other chemical as well ?

Not necessarily.

I recently had to dump some HC-110 'European strength' concentrate that had gone the colour of coffee. And I like my coffee quite strong!

It went from a pale orange colour, where it was still useable at a lower dilution (6+1) to deep brown and totally useless. This happened in the space of 6 to 7 weeks in a 1/3rd full and tightly stoppered bottle.

But I do use collapsible bottles and store them "full" out of the light.

All plastic bottles are gas-permeable to some degree, and collapsible ones need to be made of thinner and more flexible plastic than rigid bottles. It's kind of a self-defeating design flaw.

IME you're better off using a variety of sizes of glass bottle that can be filled almost brim full. And the caps need to be properly airtight.

An old trick was to put glass marbles into chemical bottles to take up the airspace. I suspect that works a lot better than 'inert' gas sprays and concertina plastic bottles.