After years of research & development, CineStill has now formulated the only safe and consistent way to process stills with the same characteristics Hollywood expects, from the comfort of your home with the Cs2 “Cine Simplified” ECN 2-Bath Kit.
For those who wish to dabble in the motion picture workflow we have formulated some original at-home solutions, which are accurate to Eastman Kodak sensitometric standards. This 2-bath process simplifies the original 10+ step ECN-2 process, with uncompromised quality and accurate characteristic curves, while making it safe and foolproof for at-home use. Any motion or still photography film can be processed in this simplified 2-bath powder kit, resulting in a low-contrast color negative that is suitable for the motion picture workflow and scanning.
Our Cn2 “COLOR NEGATIVE” developer is combined with the prebath accelerant (which kicks off development) to produce proper ECN-2 density. The bleach and fixer baths are combined with the stop and wash baths in our single Bf2 “BLEACH&FIX+STOP” bath, to reduce risks to health & safety and processing defects caused from hazardous chemical carryover. After a final washing of your film you will have CineStill negatives matching Kodak’s characteristic curves for proper motion picture processing.
It may be a less complicated process than ECN-2, but Cs2 is actually more advanced chemistry, utilizing chemical compounds and technology which didn’t exist when ECN-2 was originally designed. ECN-2 was formulated around the mid-1970s, with the available technology of the day. Even though our Cs2 kit is simplified and safer, we didn’t skip or compromise any of the designed functions of the ECN-2 process. Whether it be with the color developing agents or the combined baths, we don’t settle for incomplete formulas that omit essential active components (e.g. Antifoggant to prevent base-fog buildup, Anti-Calcium to prevent precipitate and contamination, Ammonium Thiosulfate to fully clear silver and dyes, Development Stop to prevent color staining, etc). Proper ECN-2 negatives. No compromises. No BS. We’ve got you covered.
* Not intend for RA-4 chromogenic printing.
* If rem-jet is present, it can be manually removed under running water, after development.
+ Cs2 Pros
Great for extremely high contrast scenes or to achieve the low-contrast cinematic look of motion picture negatives
Optimized for motion picture logarithmic scanning and ECP film printing
Advanced active chemical agents formulated for motion picture processing
Simplified and safer 2-bath solution
Reduced risk to health & safety and processing defects caused from chemical carryover
None of the caustic compounds or poisonous byproducts associated with ECN-2 processing (such as lye, sulfuric acid, hydrogen sulfide and sulfur dioxide fumes, or highly toxic cyanide gas)
Ships worldwide without Limited Quantity Hazardous (ORM-D) regulations
No special processor or additional components needed
- Use standard processing tanks and reels
Excellent for bleach bypass processing with F96 rapid fixer
- Cs2 Cons
Not compatible with still photography RA-4 chromogenic paper
More difficult to maintain higher developing temperature than Cs41
Less film capacity than the Cs41 process
Recommended +1 stop of overexposure
Thinner low-contrast negatives can be more difficult to scan
Cs2 vs Cs41 Film Processing
ECN-2 and C-41 processes were originally formulated back in the mid-1970s to produce negatives for different purposes. Large scale ECN-2 processing was designed to produce consistent, thin negatives for quick printing on high contrast ECP-2 film with short exposure duration, to save time and money. Denser C-41 negatives could take up to 8x as long to print or scan, and time is money when printing 24 frames per second. ECN-2 negatives have an optical density range of around 1.6, while C-41 film is about 2.2, inherent of the process rather than the emulsion itself. This equals up to a 30%+ increase in tonal and contrast range. The target contrast gamma of the Cs41 process is between .6 to .65, but Cs2 processed film is only .45 to .55. Even if you adjust the processing time to get a denser ECN-2 negative there will still not be enough of an increase in contrast or color separation to match the curves of a C-41 negative, since it also lifts the base density of the film. Films processed in Cs2 exhibit much lower color contrast, with muddy whites and blacks when printed on RA-4 color paper. Conversely, any film processed in Cs41 would have too much contrast and density range to be compatible with motion picture printing. When it comes to making a photograph, cross-printing is more of an issue than cross-processing.
Above: 21-step Sensitometric Characteristic Curves.
Top left: 800T with Cs41, Top right: 800T with Cs2, Bottom left: 800T with Cs41 vs Cs2 neutral density curves, Bottom right: Kodak’s target curves for 5219 match 800T with Cs2.
The difference between Cs41 and Cn2 processed films is the contrast curves produced in development, not the color quality or the halides. The color developing step controls the contrast curves but leaves the dynamic range of the negative unaffected because the density range is increased with the contrast. The limit to dynamic range would only be in the cross-printing but not when scanning. Color developer pH and temperature shifts color from colder to warmer, because as it increases (from 102-106ºF) so does the depth and activity of the developer on the lower green and red-sensitive layers. The Cs2 process is warmer than the Cs41 process, and it also yields a warmer color temperature. Color temperature and density can easily be corrected in printing but contrast cannot.
You can always scan any type of film, processed by any method you prefer. C-41 films may be processed in Cs2 chemistry to achieve desired results and vice versa. You can’t however go back and make an ECN-2 negative into a C-41 negative for printing. Both can be scanned with a density range suited for the respective process, but ECN-2 negatives require added contrast and care. Cs2 processed film will exhibit a more flat, linear curve, whereas Cs41 will render a higher contrast S-curve with more color separation. The characteristic curves produced by each process are designed to match the target densities for printing. The Cs2 process is great for extremely high-contrast scenes or to achieve that “flat cinematic look”. A lower density range (below 2) logarithmic scan of a Cs2 processed negative and further color grading is recommended to create a pleasing still photograph.
The Cs2 process can perfectly match the published sensitometric curves for a motion picture negative, designed to be accurately printed as a positive on ECP-2 film or log scanned as a digital intermediate for color grading. Developing CineStill color films in Cs41 chemistry as intended yields contrast curves, color separation and density range that compliments chromogenic printing and scanning for still imaging, making it easier to make beautiful photographs.
Cs2 is Safer than the ECN-2 Motion Picture Process
The Eastman Color Negative motion picture process involves a specific mechanical and chemical process for motion picture labs to produce long lengths of motion picture negatives, which print consistently on ECP-2 print film for projection. Motion picture processing machines use caustic chemicals that you don’t want in your home, such as sodium hydroxide (lye) and sulfuric acid (battery acid), which can cause chemical burns from handling. In addition to PPE, industrial exhaust vents are needed to carry away dangerous vapors and provide for the safety of the lab operator. Emulsion acts like a sponge and carries color developer into the acidic color stop bath, generating poisonous hydrogen sulfide and sulfur dioxide fumes. Heat and any acid added to the ferricyanide bleach can liberate highly toxic cyanide gas, along with the forming of Prussian Blue deposits on film, reels and tanks. Simply bypassing the hazardous color stop bath and going into the ECN-2 bleach will oxidize the color developer remaining in the emulsion, and cause severe staining to the film. Safer B&W stop baths (e.g., citric or acetic acid) introduce byproducts that cause leuco-cyan dye problems in the red-sensitive emulsion layer (i.e., green images) and interfere with the bleaching step. Additionally, bleach carryover into the separate fixer causes the film to be mottled with smears of color. This is why the ECN-2 process also specifies Solution Crossover Devices with multi-stage countercurrent washes between steps. If you are going to follow the ECN-2 Specifications for Processing KODAK Motion Picture Films you must use all of the proper equipment as well. None of these byproducts occur in the CineStill Cs2 Process.
With the Eastman Color Negative process a Prebath step softens the rem-jet backing for removal and accelerates development. The removal must be done so that none of the backing material sticks to the emulsion surface, through the combined action of water jets and buffers contacting the base side, removing all of the backing and residual residue. The Color Developer agent reduces exposed silver halides in emulsion into metallic silver, oxidizing the dye couplers incorporated within each layer of the emulsion to produce color images. The Stop Bath halts development and prevents oxidation of the dye couplers when entering the bleach. The washes prevent chemical carryover between baths. Bleach converts metallic silver, formed during color development, to silver-halide compounds that can be removed by the fixer. Rapid Fixer then converts all silver-halide compounds to soluble silver thiosulfate complex salts that are removed from the film in the fixer and subsequent wash. The wash and Final Rinse removes residual soluble silver thiosulfate and chemicals from the film, and prevents water spots and biological growths.
See more at, www.kodak.com/uploadedfiles/motion/h2407.pdf
If you already process your own black and white film, with this kit, there is no reason not to process color negative film at home as well! It is specially formulated without compromise for modern color films. All you need is heated water, a thermometer and any simple tank and reel system!
Download Cs2 ECN 2-Bath Kit PDF Instructions
Download Cs2 ECN 2-Bath Powder Kit Safety Data Sheet
Photochemical Waste Management