Above: This is a page spread from my in-studio journal. I was watching the Westminster dog show so of course I had to pick up my sketch book. I'd like to say, because of my allegiance to Alaskan Malamutes, that Ricky was robbed, but the Dobie who won his group, and even the boxer bitch who came in second, were excellent dogs. These sketches are in a 9 x 12 Fabriano Venezia journal. I used a Faber-Castell Pitt Artist's Calligraphy pen, black. (They also come in a brown and a wine color I believe.) Click on the image to view an enlargement.
Left: Here's a detail of the Cane Corso dog's face. There are letters around the image, A through F. Each letter is near a line which you can see is different in thickness and texture from its siblings. All these lines come out of the same pen simply by varying angle and pressure.
I enjoy using this pen on this paper because it practically squeeks along the surface, cutting in the directions I desire. But I also like working with this pen on softer papers, other watercolor papers, printmaking papers, slicker drawing papers, and so on. You get the idea, I find this a very versatile pen—especially when I want to work large and the nibs on my Staedtler Pigment Liners are not large enough to make quick work of a large page.
The other great thing about this pen is that on pretty much every paper I've ever tested it on it is waterproof almost immediately. Sometimes it's the only pen that's waterproof in any span of time that's worth waiting.
So if you're looking for a versatile, hard working pen for sketching you might want to check this one out. It's fun to write with too.
(And I'm not affiliated with the company in any way—I'm just a fan.)
You'll see me jump to using this pen a lot in my journals. It, along with the Pentel Pocket Brush Pen and my Staedtler Pigment Liners, is one of my default pens.
To see more sketches with it you can check out "Adjustment P10 Journal" in three short videos that start at this link. (The sketches in "P10" are mostly on softer papers like Rives BFK.)