I’ve been using Waka-Uguisu in two pens, a Pelikan M400 with medium nib and a Kaweco Dia2 with extra-fine nib. That photo above shows it in the Pelikan.
I was a little wary of Waka-Uguisu, honestly. I’m not the biggest fan of the color avocado green, and to me Waka-Uguisu looked avocado in most photos I saw.
But it turns out that there’s more yellow in Waka-Uguisu, so it’s really more of an acid green. The color is clear, bright and cheerful.
I think Waka-Uguisu looks great on cream-colored Tomoe River paper. Here is a large writing sample showing first the Pelikan with medium nib and second the Kaweco with extra-fine.
Waka-Uguisu is a light-colored ink, but it seems to concentrate and darken in that extra-fine nib, so it’s very legible. I love inks with that quality.
I am not much of a sheen-producer, but a bit of sheen looks to be possible from Waka-Uguisu in the right pen. That said, it doesn’t appear to be a huge sheener like Sailor Tokiwa-Matsu.
But what a nice color. Here is Waka-Uguisu in the extra-fine nib on Rhodia paper.
I like both colors I get from Waka-Uguisu, the darker and the lighter. Here again on Rhodia.
Waka-Uguisu does pretty well on poor paper, at least with the medium and the extra-fine nibs. It is a wet, easy-flowing ink, so I do see showthrough on lower-quality paper. But I’ve seen no bleedthrough, and only a little feathering, and that only on poor copy paper.
On Staples Sustainable Earth, feathering is in check. Here is a closeup with the Pelikan with medium nib.
The color and shading are still nice, even on absorbent paper like Sustainable Earth.
Waka-Uguisu does not have much water resistance — none on Rhodia, and just a bit on regular paper.
Usually that means an ink that’s easy to clean. Actually, however, I have not been willing to clean out either pen yet: some sacrifices are beyond me. If Waka-Uguisu unexpectedly turns out to be hard to clean, I’ll come back and edit this paragraph. But I think that’s incredibly unlikely.
Because, take a look at the dyes; here is paper towel chromatography of Waka-Uguisu.
Very yellow, for a yellow-green. I think that yellow gives Waka-Uguisu its lightness and softness, but the bright green and blue dyes provide a nice balance, perking it up. That accounts for the cheeriness, I think.
And just for fun, I compared the chromas of three Sailor green inks. From left to right is the discontinued Sailor Jentle Epinard, the currently available Sailor Jentle Four Seasons Tokiwa-Matsu, and this ink, Waka-Uguisu.
I do have a number of yellow-green inks, but none is exactly like Waka-Uguisu.
To me, Waka-Uguisu is cheerier and clearer than the more avocado Alt-Goldrün. But not as bright and cheery, nor as green, as Diamine Meadow. Waka-Uguisu does remind me of the Lamy Al-Star in Charged Green, but that pen actually matches even better with the two inks in the middle, Chiku-Rin and Alt-Goldgrün.
I haven’t yet tried Waka-Uguisu in a very dry-writing pen, nor in a pen with a very wet, very broad nib. But I’m thrilled with it in the two pens I’ve used so far.