Waitangi photo exhibition casts light on tā moko at Te Kōngahu Museum

A digital portrait of musician Rob Ruha showing his digitally enhanced tā moko, and a wet-plate photograph where the process causes the tattoo to disappear.

The Māori word puaki means to come forth, show itself, emerge, reveal, give testimony — making it a fitting title for a time-bending photo exhibition at Te Kōngahu Museum of Waitangi.

In Māori culture, it is believed everyone has a tā moko under the skin, just waiting to be revealed.

But when photographs of tā moko were originally taken in the 1850s, the tattoos people did wear barely showed up.

Through a trick of light and chemistry, the wet-plate photographic method used by European settlers and travelling photographers served to erase this cultural marker.

The process, first used in the early 1850s, required a subject to stay still and non-blinking for at least 30 seconds, the effect often giving the subjects in old portraits static expressions, pale eyes and blanked out facial features or blemishes, including tā moko.

As the years went by, this ''blanking out'' was paralleled in life, too, with the ancient art of tā moko increasingly suppressed or made redundant as Māori were assimilated into the colonial world.

However, tā moko, and kōwae on women's chins and lips, has undergone a resurgence since the late 20th century.

In "Puaki", photojournalist Michael Bradley has reclaimed the near-obsolete, wet-plate photographic technique as an original, striking way of showing the revival.

Using the technique alongside the latest in modern technology, "Puaki" showcases the tā moko of 23 Māori participants through both wet plate and digital photography, and video interviews.

One technique proves the art and power of tā moko is boldly alive; the other shows how it became invisible.

The exhibition at Te Kōngahu Museum of Waitangi will run until Sunday, September 2.

Bradley could not think of a better place to give the exhibition its first showing.

"Te Kōngahu Museum of Waitangi is a very important place, and it's an honour to bring these images and stories to the museum, documenting the place of tā moko today," he said.

Collections and Public Programmes Co-ordinator Caitlin Timmer-Arends is excited "Puaki" has debuted there.

"The exhibition has so many themes that correspond to Waitangi and Aotearoa. Featuring well-known New Zealanders, [it] gives the opportunity for both our local and international visitors to experience tā moko and its re-emerging place in our society."

While Waitangi National Trust staff cannot identify how many of the 900 visitors to the museum in its first week were there primarily to see the "Puaki" exhibition, it has become a talking point on comments on social media and other forums.