Rapid fix came about just after World War II when ammonium thiosulfate became commercially available as a 60% solution. Such a solution dissolves silver salts while leaving the metallic silver image alone (for the emersion times we use). Sodium thiosulfate has been in use since 1837.
C41 black and white film how to#
From the inception of photography, the search was on as to how to render the silver image permanent. Since developed grains have a lot of sharp edges and surface area, maybe theyĪlso dissolve glen_h The two fixers we use are sodium thiosulfate, nickname "hypo" and ammonium thiosulfate, nickname "rapid fix" because it works twice as fast. I was thinking that the colloidal particles were smaller, and dissolve faster. If I run across a roll like this in the future I'll probably stick with C-41. The positional dependence might have something to do with the flash and uneven lighting fooling the software. If I had more post-processing skills and better tools I might try what you suggest about the color correction. They're not worth a huge amount of effort. )Īnyway, I process these for practice and to try different things. I'm going to try to let them know that I have a couple of pictures but my wife can't remember their name a the moment. This roll was out of one of a bunch of cameras that came from a very loose acquaintance of my wife's. If they're really interested in getting them processed I'll mention film rescue. I'm hesitant to volunteer that I might attempt to process it because I don't want to feel obligated to nor do I want to create any expectations in case I screw it up. If the person I bought the camera from is likely to be connected somehow to the person that took the pictures I'll ask them if they want the roll back or not. Once in a while an old camera will end up in my possession with a roll of film still in it. In this case the roll had been sitting in my fridge for 18 months and my current batch of C-41 was old enough that I didn't want to use it on anything important to me, so in this went. I wasn't consciously thinking about the cost aspect of it, that makes sense. If you can do a x-axis dependent color correction, it might come out better. In the color image, it looks like a position dependent color shift. The slower speed of Kodacolor II gave you a better chance, too.
That way, you get two chances, but probably only worth doing Then bleach the developed silver back to silver halide, andĭevelop with C41 chemistry. First, you develop as black and white,Īnd get what you can from it. There is actually a Kodak recommended way to do this.
C41 black and white film iso#
Since none of the pictures were mine, and at ISO 1000, in addition to unknown storage I did it on a roll of Gold 1000 that came in a used camera that I bought. If the results are quesitonable that it isn't worth the cost of C41, then black and white is a good choice. They adjusts contrast as they bolster the cyan dye image. These residual tints are actually two positive “corrective” images superimposed on the three negative dye images. Cyan is difficult to get “right” thus it needs some assistance. Their purpose is to bolster the cyan dye contained in the red-sensitive layer. The Hanson Orange Mask consists of residual magenta and yellow dye couplers. Its persistence adds a uniform density that makes these negative difficult to scan or print (not impossible).ĭo not confuse the Carey-Lee filter with the Orange Mask typical of color negatives. Should the film be developed in a customary black & white process, the Carey-Lee filters remain. Thus all traces of the Carey-Lee filter are removed. The halogenated silver is thus made soluble in the fix. When C-41 film is developed per standard, the bleach step chelates (combines silver with a halogen). Thus the more energetic blue light is checked. The particle size is such that blue light photons collide and are absorbed, while red and green photons pass with ease. Colloidal silver is super fine silver particles in suspension. This layer consists of a clear gelatin binder holding colloidal silver. To prevent blue light interaction, a Carey-Lee filter layer is fabricated just below the blue sensitive emulsion. Should blue light reach them, crosstalk occurs. However, they never lose their sensitivity to blue. These emulsions have been treated to force them to become sensitive to colors other than violet and blue. Its purpose is to preclude blue light energy from reaching the underlying green and red sensitive emulsions. This is because negative color films have a yellow filter layer just beneath the top blue-sensitive emulsion. C-41 films can be cross processed in black & white chemicals, however the results will likely be substandard.
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