Topic: Caffenol...day 16 R.I.P.

[astrobeck]

My caffenol finally died!

After 16 days it is mostly dead.
I was still developing for 8 minutes, but the negative is extremely thin and worthless in a practical world.

I used the same caffenol batch I mixed up on November 26 and kept in a bottle with the air squeezed out.

Fresh= perfect developing at 8 minutes, nice crisp negative evenly developed, easy to scan.
4 hours old= still perfect at 8 minutes, still crisp and evenly developed, easy to scan.
1 day old  = still good even development at 8 minutes, easy to scan.
2 day old  = still good even development at 8 minutes, but has signs of weakness, still easy to scan.
4 day old  = okay, even development at 8 minutes, but definitely has signs of being thin, negative still looks good, easy to scan, tweaked in PS for levels.
8 day old  = surprised to see the negative turn out at 8 minutes, somewhat thin, but usable, fairly easy to scan, more tweaking in PS levels.
16 day old= failed at 8 minutes, negative too thin to do anything with.

My conclusion is that caffenol will keep for a few days in a sealed bottle with the air squeezed out. 
It "might" even work okay on day 16 if additional time was figured in to the developing time, but why chance it on a photo that means something.
Just mix fresh for the very best results.

Thank you all for your time and patience on this.

Now I'm off to take 12 photos with my backwards Brownie since it's 12/12/12!   
Becky

[Francois]

Just to link up with the game I made
http://www.filmwasters.com/forum/index.php?topic=5720.0

I must admit that I'm both surprised and disappointed. I was expecting it to last a lot longer. But on the other hand, considering it was what I essentially call an "office reject" has me pretty surprised.

So, on average conservation is good for a few days but bad after about a week.
I wonder if it would keep longer in the fridge... or if it freezes well?

[astrobeck]

I kept the caffenol on the floor in the bathroom which is the coolest room in the house and stays around 69 degrees.

I think it just exhausted itself over time and use and since I got 6 sheets developed out of it before it failed, that's fair enough for me.  Plus if you do the math, it's VERY cheap developing.

I have the mixture marked and saved and might experiment with it further and see if there is anyway to rejuvenate it, but honestly it seems like a lost cause at this point.

:-)

[sapata]

Now...just imagine if it had exhausted on the day 12? it will be on the 12.12.12 !!! The world would had finished by now!!!

It's nice that you put all this effort on doing this Becky... I haven't tested caffenol yet (and it's more likely I will soon as chemicals are so overpriced in here...) so it's good to know all this 

[Terry]

Give it a try Mauricio; you'll be pleasantly surprised.  And the smell isn't THAT bad....

[Ezzie]

My mix doesn't smell that bad at all. I think the Kodak fixer I use smells worse.

[sapata]

Give it a try Mauricio; you'll be pleasantly surprised.  And the smell isn't THAT bad....

I'll have to... at least at the beginning until things get back to normal. There's also Parodinal in my list of homemade developers to try...

[Terry]

I even use the store brand generic coffee and it works perfectly. 

[Francois]

I have the mixture marked and saved and might experiment with it further and see if there is anyway to rejuvenate it, but honestly it seems like a lost cause at this point.

:-)

Personally, I wouldn't bother to try and replenish it.
Though I wonder if it stops working because the ph changes or because the solution oxidizes?
Caffenol-C contains an antioxidant... does that make it last longer?

I guess it would be easily possible to do an entire master's degree in photochemistry simply on the various versions of caffenol!

[Jack Johnson]

Just pinging this old topic. I have just enough left over on a now 8-day old batch that I'm testing tonight.

If I'm happy with the results I might start doing something like mixing 2-liter batches at a time and keeping it in one of those collapsible camping waterbags. It would sure be nice to soup some film at the drop of a hat.

[astrobeck]

I should remind everyone that I was using that test batch on 4 x 5 sheet film.

Just last week I developed a roll of Fuji Acros 100 (120size) in  a fresh batch of caffenol which turned out fine, then about 30 minutes later developed a roll of T-Max 100 (120) size in the leftovers and the T-max negatives were quite thin.  I don't know if it was the film brand, or just that the caffenol wore out after the first roll...but since caffenol is so cheap to mix, I mix fresh each time now.

I also use cheap instant coffee.  As long as it's dark roast and still has caffeine in it.
 

[Ezzie]

I have done that a number of times with no ill effects Becky. But I tend to add 1 minute for every successive film. Also, according to my personal exposure/development regime, I tend to give TMX a minute more than Acros to begin with. When using my C-C-(RS) recipe that is. Which would in a case like this mean 13min for Acros (EI 80-160) and 15min for TMX (EI 100) @ 68F/20C