Just tried printing my first B+W image using QTR and there is a clear green tint
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Any ideas why there is a tint to the image? Are Epson's K, LK, LLK Inks neutral or not?
Epson K, LK, LLK inks are not neutral, they are close to mustard/olive tint what is usual to carbon based inks.
There are two approaches for black inks: Canon and HP having near neutral blacks - these are carbon based inks with addition of some cold tint dyes in the liquid. Epson approach is different, inks are warm and neutralisation is done by adding C/M tint directly on paper.
You can receive very neutral prints from QTR, however it is not easy, and one of the highest advantages of QTR is ability of duo/tri toning by curve blending.
ABW is far from neutral, but of course closer than anyone's first attempt to QTR. Many things depend on the paper tint you use, since there is no clear "neutral" definition once you change papers.
Good luck with QTR, it is worth trying if you have a lot of patience! Results can be outstanding.