GCO to protect digital negatives

As I have been learning about producing digital negatives using the piezography pro inks, I see that it is recomended to use the GCO for negative production as it helps protect the negative. I was wondering what your experience was by doing this? It is my hope that I could store the negatives for future use when printing silver prints. Will the GCO protect the negatives and for how long? How would you recomend these negatives be stored? Or should I forgo the GCO all together?
sincerely
marty

Hi Marty,

I do not use GCO as a practice as it can slightly soften acuity. The negatives are rather fragile and we do not typically store ours when we make prints for customers at Cone Editions Press because it is a better practice (for us) to have a negative that has not sustained any damage. We use hydration in our platinum printing and the sensitized media is still slightly moist. So on a subsequent printing we may want a fresh neg if we are hydrating in the high 60s rH%. I would harden your negatives overnight - as they do change density. I have our system calibrated for only a one hour dry down. And the negs are a little fragile for same day use but this allows us to take in a project and print it on the same day by calibrating to a one hour dry. I also now have calibrations for 2 day dry. We did some data in November that did give different results for one hour forced dry, one day natural dry, two day natural dry. The negs are a bit more sturdy as well with the 2 day natural as well as tending to have slightly more density that can be calibrated. We store in archival negative sleeves that open from the side so we do not have to slide the neg out. Having said that I am going to give you a good starting point to use to add a GCO to your linearized negatives… You would replace the LLK and all of the 0s following it with the following - as it is only a moderate amount:
#LLK curve
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and others may have different experience especially if they tend to store negatives.

Kind regards,

Jon