What’s the difference between Hansa Yellow Deep (PY65) and Isoindolinone Yellow Deep (PY110)?

These two deep yellows are very similar in hue, so what’s the difference?

I find Hansa Yellow Deep (this Daniel Smith one, at least) to be slightly more yellow, where as the Holbein Isoindolinone Yellow Deep that I tested is slightly more orangey. If I’m squinting, HYD looks more dull in masstone but brighter in midtone. They are, however, nearly identical.

They also have very similar properties. Both are bold and smooth (non-granulating) colors. Both are semi-transparent, with IYD being a bit more transparent.

Color Mixes

Quin Coral

Extremely similar. In mixes, this particular Iso Yellow Deep seems a bit more streaky compared to this particular Hansa Deep, but I’m not sure if this is a general characteristic of all versions.

Quin Rose (PV19)

These both make bright, clean grapefruit corals.

Ultramarine Blue (PB29)

I found it easier to get dark blues with HYD. Both make grayish non-greens.

Phthalo Blue (PB15:3)

Both of these have the capacity of make rather muted greens. Again, darks were easier with HYD.

Phthalo Green (PG7)

Both of these make a range of bold, bright summer foliage greens. The combination of PG7 and PY110 is used by some companies for a premixed Hooker’s Green (e.g. M Graham’s).

Real-Life Situations

I tested both paints, as well as the more orangey Benzimida Orange (PO62), in a series of thumbnails that mimic situations in which I’d use a yellow-orange: a tropical sunset with Quin Rose; a cityscape dusk with Ultramarine; and a foliage color when mixed with Phthalo Green. (Note: this page uses the DV version of Hansa Yellow Deep, whereas the mixes above used the DS version.)

Again PY65 and PY110 fared very similarly. PO62, to my eye, did not look as good in skies and makes significantly duller green mixes – it was hard to keep it from going gray.

Conclusion

I find it hard to predict which is going to be brighter: a more transparent color (like Isoindolinone Yellow Deep), which allows more white to shine through, or a slightly more opaque color (like Hansa Yellow Deep), which is bright and bold on its own merits. At different times and in different situations, each seems to be superior, and most of them time they seem about the same.