I apologize for not responding sooner, we have been working with artists in our studio over the past few weeks, therefore I haven't been on my computer as much as usual.
After reviewing your attachments and order history, and comparing your prints to mine made with Piezography Neutral inks (from what I can see from your attachments), I believe your shade 6 ink in the LK channel is slightly too dark. There looks to be about the same slight difference in the shade 5 and 6 ink drops as there is in the Ink Separation printout, so I am curious about your shade 6 ink, and would like to evaluate it. I see you just purchased more shade 6 ink, do you plan to use the new ink in place of the shade 6 you currently have? If so, please send your current bottle of Neutral shade 6 ink to the address below for me to test.
Please let me know if you have questions, need assistance in changing ink in this line, how things look after changing this ink, or if there's anything else I can help you with.
Best regards~ Dana
17 Powder Spring Rd
Topsham VT 05076