I may now announce the first working Caffernal and its recipe is following, but please understand what I mean. To start, let us consider the balanced equation of the reaction between Ascorbic Acid and Sodium Hydroxide to give Sodium Ascorbate and Water:
C6H8O6 + NaOH → C6H7O6Na + H2O
176 g + 39 g = 197 g + 18 g
The complete reaction needs 4.5 times (176/39) Ascorbic Acid in relation to Sodium Hydroxide.
But we don't want the complete reaction because there is a risk of surplus of Sodium Hydroxide that will give a high pH, or a risk of low pH that combined with coffee can go acidic and no development will take place. After some disasters, my starting point was fixed at 3 parts of Ascorbic Acid in weight for 1 part of Sodium Hydroxide and I end with a basic pH of 11,6, but still to high for ascorbate developer. So, I added coffee as acid to lower th pH to 10.6. And here is the whole procedure:
Preboil 1 liter water for 10 minutes and let cool. Add 5 g Potasssium Metabissulfite as Oxygene scavenger. Then use just 100 ml of this water in a beaker and dissolve 60 g Ascorbic Acid in it. Then put the beaker in a bowl with cold water and add 20 g Sodium Hydroxide and stir (don't forget gloves and googles). Pour some more of the cold preboiled water, say, 50 ml. The color of the mixture is light yellow. At the end of the solution measure the pH which will be about 11,6. Now weight about 60 g soluble coffee and go on adding to the soup and measure the pH. When you reach 10,6, more or less, stop. Add 5 g Potassium Bromide as anti-fog (it is enough). Add some more of the preboiled water to make 250 ml and store in an amber bottle of 250 ml. You have prepared the stock solution of Caffernal.
According to my experiments, for each 100 mg Sodium Hydroxide more than the necessary, you will have to put more 1 g of coffee. Suppose that by mistake you putted 2 grams more of Sodium Hydroxide, this will need 20 g coffe to neutralize it. So, be careful and don't waste resources, unless you want to change the proportion Ascorbic Acid to Coffee for a developer with other properties, more grain, more contrast and so on.
And so we have constructed a developer that can be used very diluted. I have been using it in dilution 1:50 and I need some 60 minutes at 25ºC to develop well the film Ilford FP4.
Have fun with Caffernal!
Note: For better understanding, I add a small explanation in red.
2.nd Note: Sodium Ascorbate has a pH between 7.4 and 7.7. Without a surplus of alkali it will not develop.
Monday, July 15, 2013
Tests with Caffernal
The photo above was taken with a Adox Golf 63 at 1/200 and f/8 with Ilford FP4. No software enhancement was applied, just as it came from automatic luminosity of the scanner.
Caffernal looks like a fine grain developer, low contrast and good restitution of the whole grey scale.
In the dilution 1:50 it takes a minimum of 60 minutes to develop at 25ºC.
Now, comparing this developer with the Caffenol C+, using Sodium Hydroxide as alkali too, I found a way to change the properties of Caffernal, I am about to test these possibilities.
The aim of the changes is to make Caffernal faster than it is now. In comparison with Rodinal it is some 4 times slower or more. The contrast can be also pushed a little, I think.
Saturday, July 13, 2013
Caffernal advances
Today, because it is too hot during the day, I left home about 8 o'clock in direction to sea, where I would like to make some pictures with my Holga 120 GN adapted to 30 photos 20x30 mm. The weather was very cloudy and I had to use the bigger aperture of the Holga and the sharpness of the photos are not ideal. Once at home, I developed in Caffernal dilution 1:50 for 50 minutes at 25ºC. Well, it needed some more minutes, maybe 60 minutes, which is consistent to my experience using caffenols with 1g/l coffee and Vit. C. OK, but the pictures could be sacanned without problem, dark areas have less details.
On the other hand, the highlights are superb, it was possible to see the small sky clouds shadows. I think in a not so cloudy day, the clouds would be fantastic.
Here are some choosen photos of the series:
On the other hand, the highlights are superb, it was possible to see the small sky clouds shadows. I think in a not so cloudy day, the clouds would be fantastic.
Here are some choosen photos of the series:
The smal differences in sky density could be registered |
Good grey scale |
Testing depth of field, setting for group |
Rock and sand |
Rocks and water |
More rocks, see difference sky/horizon |
Head of the big chief |
A couple photographing |
The beach sight from above |
Another sight of the beach |
The typical portuguese coast to Atlantic |
Friday, July 12, 2013
Caffernal
After having succeeded with a Caffenol using Sodium Hydroxide as alkali, the Caffenol C+, I wrote an article about it at ipernity.com, I started a series of experiments to see the limits of how few I must use to develop. From many developers made with some logic I experimented, only perhaps the Caffenol 3335 (3 g Vit. C, 3 g Sodium Hydroxide, 3 g Coffee and 5 g Potassium Bromide per liter) is worth a try. But maybe you should raise the potassium bromide to 10g/l. Or, wait, you don't need so much, the proportions are not quite right as I discovered later.
But the new project I have is to find a based on coffee and vit. C developer that works similar to Parodinal. I started calling it Caffedinal but I worked so hard until I got reasonable results that I changed the name to Caffernal. I am still experimenting but I can already say it will be a reality. The photos below were made using a 1:25 solution and 20 minutes at 27ºC and I think it will work at 1:50 solution too, already tried but the duration was short (45 minutes), images too weak.
The final recipe is still not fixed but it is more or less obvious that coffee, vit. C, Sodium Hydroxide and a pinch of preservative and restrainer will also be included.
But the new project I have is to find a based on coffee and vit. C developer that works similar to Parodinal. I started calling it Caffedinal but I worked so hard until I got reasonable results that I changed the name to Caffernal. I am still experimenting but I can already say it will be a reality. The photos below were made using a 1:25 solution and 20 minutes at 27ºC and I think it will work at 1:50 solution too, already tried but the duration was short (45 minutes), images too weak.
The final recipe is still not fixed but it is more or less obvious that coffee, vit. C, Sodium Hydroxide and a pinch of preservative and restrainer will also be included.
Picture 1 - Semi-stand development, not recommended, see the shadows of the perfuration |
Picture 2 - 3 minutes constant agitation and the one minute every 5 minutes |
Picture 3 - Same as Picture 2 |
Friday, July 5, 2013
Finally some color again!
In a thread at Flickr, I discovered this picture of Marschal A. Fazio (Pothman), that he made using Rodinal and hair dye in a reversal (?) process. He says:
Since yesterday I am trying to reproduce the experiment, I have nothing really exciting yet to show you, but maybe some of theses days, who knows.
Report of what I have tryied until now:
I prepared the developer like suggested, 3-4 ml not of Rodinal but self prepared Parodinal for 500ml water and about 10ml hair dye, but not the same brand of Loreal. I was so convinced of the success that I went out and exposed a 36 Agfa 100 and developed with this developer. After the first development I filled the tank with a bleach bath of a Tetenal kit for some 4 minutes and oppened the tank to expose the film to light. I expected a blank film but no, it was developed in black and white, looked very nice as black and white pictures. I submitted then the roll to a stronger bleach, Potassium Dichriomate + Sulfuric acid and the result was to bleach out almost all, leaving the roll damaged. No, this way it doesn't go. I need another bleach bath...
I exposed then short pieces of film at home and tried again, the same developer but as bleach I used this time Betadyne which takes hours to act but goes safer. I bleached for some 3 hours and then exposed to light and redeveloped. I have got color pictures but very weak. This was yesterday!
Today I restarted exposing small pieces of film at home and develop them using Parodinal and hair dye. I read somewhere that Parodinal or Rodinal alone is a very weak color developer too. So, this time I took as first developer only a 1:50 solution of Parodinal for 10 minutes only, stiring constantly. Then I submited the film to 45 minutes Betadyne and the result was a almost B&W developed film, without the orange mask, the Betadyne removed the orange mask but leaving the silver untouched. I divide the experience in two parts, cutting a portion of the film to be fixed and washed like it was and the other portion I left in Betadyne for one hour more, controling the process until I see that the silver was bleached leaving a little a weak image of dye. Then I redeveloped in the same Parodinal with two spoons of the first prepared developer of hair dye. The image got more density althought the color restitution is not that good.
Example of the first part, bleach during 45 minutes with Betadyne |
The same image warmed with software |
Direct scan of the 2 hours bleach + redevelopment with Parodinal and a little hair dye only |
From the same second part but enhanced with software |
I wonder what could have happened if I used a little more hair dye in the second developer.
Wednesday, July 3, 2013
Difraction rings of the Sun photographed with a Holga
By chance and not planed, photographing with a Holga 120 GN with a 6x4,5 mask, I centered the Sun at the edge of the upper side of the mask. My first thought was, «Oh, I have a light leak there. But looking closer I could see what happened. This was the first time I noticed such rings in the not directly exposed part of the film. The most curious is that the entire film was exposed at the B position, unwanted and is overexposed, the image is very white.
Newton rings of the Sun? |
I did an enlargement of the rings as shown below:
Well, I thought that perahps many of you never saw this effect, like me now, so I decided to make a post on it.
This happened when I was exposing a film to be developed in the not so successful new Caffenol 5555, the film was also overdeveloped but this issue could be repaired by bleaching and refixing the film. The margins are now transparent and clean like they should be from the beginning. But the film was completely black after first development.
Whether this phenomenum is physical or chemical, I don't know. I would say it is physical and has to do with the difraction of the light passing a sharp edge.
This happened when I was exposing a film to be developed in the not so successful new Caffenol 5555, the film was also overdeveloped but this issue could be repaired by bleaching and refixing the film. The margins are now transparent and clean like they should be from the beginning. But the film was completely black after first development.
Whether this phenomenum is physical or chemical, I don't know. I would say it is physical and has to do with the difraction of the light passing a sharp edge.
Monday, July 1, 2013
The future, what will be, will be.
I do not understand that transparent film, acetate or polyester, is still the preference of many of us in what «physical and chemical» photography is concerned. A transparent support is not needed anymore... Yes, I know that many voices of film fundamentalists will rise and they will start pointing advantages that only film has and so on, but think practical: I heard that Kodak stopped manufacturing papers and films (correct?), the other classic brands will follow this tendency. It is already difficult to get 120 film at the street, only at internet. Cheap alternatives like Foma and Shangai with many imperfections will serve until... well until some new brand reintroduces PAPER FILM, panchromatic, to be developed like film in tanks but that is much practical to keep and to reproduce with reflective scanners. Can you imagine a roll of 120 thin paper with some 50 pictures for your Holga or Horseman? Yes, it will come some day, nobody really tought about but it would be a very good business. Negative or direct positive paper, but negative can easily be inverted by scanners or softwares.
The advantage of such a change is to preserve the procedures we now have for film and our hobbies discovering new developers and perhaps also toners. Well, I must say, I would be very glad if some brand discovers this «mine» idea and I am sure, they would pay me some royalty when they see the results.
The picture below was made using film, but some of these days I will prepare a roll paper film and try to make the same photo with paper.
The advantage of such a change is to preserve the procedures we now have for film and our hobbies discovering new developers and perhaps also toners. Well, I must say, I would be very glad if some brand discovers this «mine» idea and I am sure, they would pay me some royalty when they see the results.
The picture below was made using film, but some of these days I will prepare a roll paper film and try to make the same photo with paper.
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