Cafenol; What Went Wrong, Part Deux

dazedgonebye

dazedgonebye

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Second roll in the Cafenol...pretty much the opposite result from last time.
Last time, I used caustic soda by accident (by stupid actually) and ended up with clear film. This time the film is so dark I can only see the images through a very bright light.
I mean all the film...out to the sprockets. :eek:
It looks like the film is so heavily coffee stained that it's just not readable by the scanner. It's a shame really, because it looks (near as I can tell) like I have some interesting shots there.
I think I know where I went wrong.
I've read that Efke film has a soft emulsion. Could it be that, between the soft emulsion and the dark roast instant coffee, I just stained it too much?

Anyone have an idea on how I might recover? My scanner can't penetrate this film.
 
My second roll is like that, try the “transparency” settings if your scanner has one.

So far I’ve managed two clear, three underdeveloped and one over but I’ve been able to get useful scans from very unpromising negs
 
16 oz of water
2 tbsp (6 tsp) sodium carbonate
3 tbsp (9 tsp) taster's choice dark blend instant.

That's about 1.5x the formula from the digitaltruth.com.

Water temp was out of the tap, quite warm here in AZ...about 26c?
Development was 30 minutes, agitation every 5 minutes.
 
dazedgonebye said:
16 oz of water
2 tbsp (6 tsp) sodium carbonate
3 tbsp (9 tsp) taster's choice dark blend instant.

That's about 1.5x the formula from the digitaltruth.com.

Water temp was out of the tap, quite warm here in AZ...about 26c?
Development was 30 minutes, agitation every 5 minutes.
Click to expand...

Hmm... sounds like it should have worked. From things I've read though, it seems that temperature is somewhat important with this formula. 20c seems to give the most consistent results and the addition of citric acid will knock down the base fog. One of these days I'll get around to mixing up a standardized (from a measurement point of view) formula with a potassium bromide restrainer even though that will kind of kill the 'off-the-shelf' nature of Cafenol. I'm just interested to see how close I can get to a commercial developer result.

Ash
 
Last edited:
dazedgonebye said:
16 oz of water
2 tbsp (6 tsp) sodium carbonate
3 tbsp (9 tsp) taster's choice dark blend instant.

That's about 1.5x the formula from the digitaltruth.com.

Water temp was out of the tap, quite warm here in AZ...about 26c?
Development was 30 minutes, agitation every 5 minutes.
Click to expand...

I think it’s the film.

I got usable negs using the same time, temp and agitation as that but at almost twice that strength; however that was on hp5+
 
Sparrow said:
I think it’s the film.

I got usable negs using the same time, temp and agitation as that but at almost twice that strength; however that was on hp5+
Click to expand...

Soft emulsion sounds like a reasonable explanation.
I'll try to scan as a transparency per your suggestion. If that doesn't work, I'm dropping the film back in the tank and figuring out how to wash some of the stain out.
 
Keith said:
My last film (HP5) turned out well with 16oz water, four tespoons of sodium carbonate, eight tesaspoons of instant coffee ... stand developed (mostly) for an hour at twenty degrees. A minutes initial agitation, another minute half an hour later and that was it!
Click to expand...

Keith, that’s how I was doing the next one except I was developing 30min agitating every 5

I’ll post the results
 
Citric acid will make caffenol unusable
ASCORBIC acid (aka vitamin C can help lowering the fog)

AshenLight said:
Hmm... sounds like it should have worked. From things I've read though, it seems that temperature is somewhat important with this formula. 20c seems to give the most consistent results and the addition of citric acid will knock down the base fog. One of these days I'll get around to mixing up a standardized (from a measurement point of view) formula with a potassium bromide restrainer even though that will kind of kill the 'off-the-shelf' nature of Cafenol. I'm just interested to see how close I can get to a commercial developer result.

Ash
Click to expand...

Now just for testing... take a strip and dip it in vinegar for a few minutes, see if the stain decreases (this is how I clean the coffee pot)
 
titrisol said:
Citric acid will make caffenol unusable
ASCORBIC acid (aka vitamin C can help lowering the fog)



Now just for testing... take a strip and dip it in vinegar for a few minutes, see if the stain decreases (this is how I clean the coffee pot)
Click to expand...

You've read my mind.
I'll be trying vinegar and whatever else is handy.
 
You could try taking a digicam snap against a bright blue sky. You might have to rig it up to take a longish exposure. Also reflections will have to be doused with some black card.
 
dazedgonebye said:
You've read my mind.
I'll be trying vinegar and whatever else is handy.
Click to expand...

that cleaning stuff for espresso machines kettles and the like

the one on the left, strips the brewing chamber in 10 min

2914774417_a6c1ab3e3d.jpg
 
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