This is not necessarily a ConeColor ink issue, however, when I attempt to make a neutral B&W print on any medium with ConeColor inks on my 3880 there is a magenta cast, particularly noticeable in the mid tones. I have made prints with the printer controlling the color management/profiles, including ABW, as well as Photoshop controlling CM/profiles and even using a profile I built several years ago with StudioPrint and with the printer under SP control and all prints have approx. the same magenta cast. All BW and color test images have been converted to Adobe RGB but I have converted them to Gamma 2.2, for BW, and to specific paper icc profiles for both BW and color with only minor cast change characteristics. What particularly bothers me is that even using the printers ABW mode the prints have a magenta cast. Only if I use the printer’s black only mode do I get a print without a cast. When I first got the printer the StudioPrint profiles and printer ABW did produce acceptably neutral BW prints. No longer. The nozzle check shows all nozzles firing and the color positions correct. Any ideas what might have happened?
After reviewing your order history, I see you purchased the set of 3880 refillable carts and ConeColor inks in Sept 2013, and it looks like you are using ConeColor inks with other printer models as well. I see you bought ConeColor ink for a 7800/9800, which uses the same inks as the 3880, with the exception of the magenta + light magenta. Is there any chance you may have refilled the 3880 carts with magenta ink from your 7800/9800 ConeColor ink set?
It can be very difficult to get a totally neutral BW print with color inks, as there is generally some sort of color cast. If you were able to get neutral BW prints from your 3880 ConeColor setup when it was first setup, but have a magenta cast now, then I wonder if you may be dealing with settled pigment, which can effect the density and color of your output, or you may benefit from using a new profile that is specific to your exact printer/ink/paper/computer setup. Do your regular color prints also have a magenta cast, or is the color cast only visible in BW prints?
Please let me know, thanks~ Dana