In the 25 years they have been collecting art, gallery owners Hellmuth Rossler and Erica Musch have amassed many important works from this region.

They include definitive oil paintings by the Ugandan Geoffrey Musaka, a group of original enamels on board by the Tanzanian Eduardo Tingatinga, and, most recently, the keynote mixed media drawing of 21 diving figures from Peterson Kamwathi’s Nairobi exhibition The Void.

Altogether Rossler reckons they have around 500 paintings and drawings, 50 or so sculptures and a similar number of prints.

Owning a gallery that adjoins their home does of course give them somewhere handy to show their acquisitions and if need be sell a few to keep the collection refreshed. So it was no surprise to find that around 20 of the 30 woodcut prints in their current show belong to them.

And what excellent works they are.

I like woodcuts. I enjoy their directness, their deceptive simplicity in mostly employing just one colour (usually black) and the way the boldest of them take advantage of the negative space between images to excite the eye, adding a little salt to the stew.

Others are intricate and delight with detail.

But to my mind the best are those that set the detail against strong shapes which they balance and harmonise.

To see some of the finest woodcuts ever made, if you like the Old Masters, Google Albrecht Durer (1471-1528) and if your taste is more modern, then have a look at those of Paul Nash (1889-1946).

If you are not familiar with the power and grace of woodcut prints, they will give you an idea of the subtlety and dynamic range that medium has offered through the ages.

To see what is happening locally, the exhibition Prints 1984-2015 is at the Red Hill Art Gallery, off the road from Nairobi to Limuru, until November 25.

The start date, 1984, in spite of its Orwellian overtones of repression and mind control, was a seminal year for print making in Nairobi. That is when the Ugandans Jak Katarikawe and Theresa Musoka gave a workshop at the Paa ya Paa Gallery off the Kiambu road, igniting an enthusiasm for the medium that still burns brightly.

In fact, Musoka’s 1984 print of a hippo surfacing and sending a spray of water across the lake is one of the highlights of this exhibition; the black bulk of the beast in the foreground, the white flecks of water… it is a masterful description of barely contained fury.

Her fellow regional pioneer Katarikawe is a more difficult artist to admire.

He has a huge reputation, cultivated by the late Ruth Schaffner at the Watatu Gallery, but these prints, while admirable in their beefy, bold way, leave me thinking, “Careless, too easily satisfied with his own work.”

There is a hit and miss quality about them, a rushed willingness to produce prints that have not perfectly kissed the block, that for me undermines his undoubted talent.

Illustrating perfectly the balance between detail and strong imagery is Gikonyo Thiongo with his suite of Kikuyu Traditional Songs, from the year 2000.

The one I liked most was Mumburo, with its procession of singers in grassy fields next to the village huts. I loved the sharp observation that patterned the picture plane; of women pounding maize, elders talking and a figure grinding corn. It was a design, an arrangement of emblematic figures on a flat sheet of paper, yet one into which you could walk to join the dance.

Other excellent woodcuts were offered by the Tanzanian Augustino Malaba who in the 1990s (no more specific than that, I’m afraid) made a print of an old man seated and smoking a pipe — a strong central figure balanced against a patterned kanga and surrounded by tall grass.

The influential Namibian Peter Mwahalukange showed The Moonlight Tree, a print of rare silvery delicacy from 1995 (contrast and compare with the clumsy bravado of, say, Katarikawe) while bringing us up to date were the three Kenyans Peterson Kamwathi, Thom Ogonga and Denis Muraguri.

Kamwathi’s Biashara was from his Nchi Yetu series of 2005 in which he used the cow as an icon for Kenya, here standing beneath a black bar code and various monetary symbols. Uniquely in this exhibition, the print was coloured, with the cow a rich purple against a delicate grey-blue background.

Ogonga had a crisp saxophonist from 2001, the brim of his hat shielding his eyes, while Muraguri’s matatu, made last year, was as gleefully chaotic as its subject.

This was a show that left me appreciating the skill of some of these artists (knives and gouges are not the easiest tools to use) and, more importantly, wanting to have a go myself.

Exhibitions rarely come more engaging than that.

Frank Whalley runs Lenga Juu, an arts consultancy based in Nairobi.