Platinum Chou Kuro ink is not great for filling in areas using a pen with a fude nib
I've watched a couple videos recently showing use of a Majohn Q1—a Chinese knockoff of the long-discontinued Tombow Egg—with a fude nib for sketching. The idea here is that the pen is so short that if unposted, it's practical to to hold it for long periods of time at a low angle to the page, taking advantage of the fude nib to do very broad strokes.
I thought that I'd give a Q1 a shot, see if it could be used to fill in large areas instead of using a brush or brush pen. I'm a sucker for high-contrast black-and-white stuff, and it sounded to me like it'd be great for doing large, filled-in black areas.
Platinum Chou Kuro has a reputation for—while expensive—being the blackest fountain pen ink out there, and sounded like it'd be a great idea to pair it with that pen and nib to fill those areas in, maximizing that contrast.
This wasn't as good an idea as it had initially sounded to me.
The problem is that while Chou Kuro is very black, it's a pigmented ink and dries atop the paper. Using a fude nib and going back over one's strokes causes the ink to be pushed around, varying its thickness and making the pen strokes visible.
Once the ink has dried, the pigment appears to prevent more ink from being wicked onto the paper, so one also can't go back and then darken areas with another coat.
The image of the man with the dog was done with a fude nib Majohn Q1 with Platinum Chou Kuro on Iroful paper.
For contrast, here's an image of the USCG Eagle done with a TWSBI Eco EF nib with TWSBI Black, also on Iroful paper:
https://lemmy.today/pictrs/image/84b808f0-c6b5-40a0-82e3-ed945fb64124.avif
TWSBI Black is a dye-based ink, not a pigment-based ink like Chou Kuro. While you can still see pen strokes, it's much less pronounced and was possible to go back and clean them up. I imagine that it's even possible to use a water brush or something and to smooth it out, since TWSBI Black isn't waterproof; once Chou Kuro dries, water does very little to it. TWSBI Black also isn't particularly prone to shading in online tests that I've seen compared to other blacks, which should also help with uniformity of brightness.
I think that, for filling in areas, having more-consistent lightness within an inked area is more-desirable than having a bit darker ink.
WebP versions of each, for anyone who might be using a client that can't handle AVIF:


