Need Help Please help me understand why my Onyx color profiles won't correctly handle chromatic red ink.

Really struggling here... let me see if I can explain this.

I work in a shop with one HP DesignJet z6100 and now we have purchased an HP DesignJet z6810 as well. We aren't TOO concerned with profiling the one to match the other (as one printer would need to be 'dumbed down' to match the other's gamut). My main concern is having two printers that we can print just about any variety of sign on. I profiled the z6810 using Onyx 18, and we're now on 19 and I have not revisited the profile. The profiling process has always been pretty easy using Onyx, except now we have the variable of this z6810 printer having Chromatic Red ink.

Onyx (the program) is fighting me every step of the way in terms of showing me data that illustrates WHY my profile will not correctly render some orange and yellow colors in my files. Our profiles on the older HPs, also built in Onyx, can print a decent gamut, and doesn't really struggle with much except maybe some darker blues and grays, which shift red. BUT on this new profile, I think there must be some setting that I don't understand which is making the z6810 incorrectly interpret how to fold in that Chromatic Red ink. For example, we can't even print jobs on this printer now that have any "pure yellow," because my profile somehow makes Onyx interpret that yellow as "reddish orange."

I built my profile for a heavyweight coated media, kind of stabbing in the dark, but with the ink setup as follows: CMYKLmLkR (so clearly it's grabbing 7 of the 8 inks for use in printing). Output is CMYKR. You'd think it would be as simple as that, but when we try to print anything like a mid yellow or a light "yellow-orange," the printer now interprets this as RED. This thereby blocks off certain jobs from being run on it, lest it have something like yellow or light orange logos. Yellow becomes "golden" and lighter oranges become "red." It seems like when I hover a color picker on a fill in Job Editor that should look more like a light gold, it will have an extreme build, something like C 0 / M 0 /Y 100 / K 0 / R 60. Why is it building a yellow with that much extra Chromatic Red ink?

While it has been months since I built the profile, I don't recall having any issues along the way that really perplexed me. I was able to profile it and get it working, and it has nice neutral grays and good shadow/midtones. BUT IT WON'T PRINT YELLOWS YELLOW AND ORANGE ORANGE. Is there something I'm missing? How do I tell Onyx to only "fold in" so much Chromatic Red? It's ruining the functionality of this printer, and our other DesignJet is on its last legs, so my time is running out only printing with this "crippled" profile.

I'm a visual person. It just seems like something should be LEAPING out at me, telling me what to do or how to set up this Red ink thing. It's not obvious and I'm at a loss. I just want to understand why this is wrong so I can fix it and return to printing normal jobs on this machine.

Thanks for any help I can get!

 

I think we tried this option already and got a strange error in the profiling window of Onyx saying that when I try to go down that route, that mode is only for separations, or can only be used with separations, something to that notion. Separations to me usually imply a 3 or 4-color PHYSICAL press.