CineStill Cs2 ECN-2 Processing Chemicals

+ 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 102-106 F) 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 ......