Obsidian Pigment Toner vs Turquoise (Phthalo)

How close are they?

ΔE 8.5, close: similar, with a visible difference side by side. Turquoise (Phthalo) is more saturated, warmer than Obsidian Pigment Toner. They are different kinds of paint: Army Painter Obsidian Pigment Toner is an opaque base/layer paint and Golden Turquoise (Phthalo) is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.

Can I use Turquoise (Phthalo) instead of Obsidian Pigment Toner?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Turquoise (Phthalo) is more saturated, warmer than Obsidian Pigment Toner. They are different kinds of paint.

Can I use Obsidian Pigment Toner instead of Turquoise (Phthalo)?

The same difference applies the other way round: Obsidian Pigment Toner is more muted, cooler.

ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.