I have a rare genetic condition called achromatopsia. A normal human has a few million rod cells (for night vision) and a few million cone cells (for daytime/colour vision/depth perception) in their eyes. I've got some rods, but no cones. This means I have poor depth perception, extreme light sensitivity, and I cannot see any colours. My world is literally 50 shades of grey :). 

I'm also severely short-sighted to the point I'm considered legally blind, and I have a condition called nystagmus, which means my eyes blink and wobble a lot. If I'm talking to you, I might appear to have my eyes closed or look off to the side.

My condition is stable – it won't get any worse, and right now there's no cure. (Although scientists in Israel have cured a flock of sheep with achromatopsia using gene therapy, and they're currently in early human trials, so that's amazing).

Mina in Nevermore Bookshop has retinitis pigmentosa (RP). This is another genetic condition where the cells in the retina degenerate over time – usually starting with rod cells, and moving onto cone cells. People with RP first notice a loss of periphery vision and trouble seeing at night. You'll usually notice symptoms as a child, and it rarely results in complete blindness. However, there are many different types of RP and ever patient is different – Mina has a specific type that has a later onset and results in severe and rapid vision loss. 

I chose RP for Mina because it's degenerative (you lose your sight over time, instead of a stable condition like mine) and also because it's a more well-known condition and easier to explain to sighted readers.

I definitely haven't ruled out writing a hero or heroine with achromatopsia in the future!

Human beings are crazy adaptable, and I'm so lucky to live in an age where technology helps people like me to live independent lives. The truth is, it's not my eyesight that makes me disabled, but the fact that prejudices and set-up of society doesn't allow me to do certain things in a certain way. But I'm here, living my best wonky-eyed life, trying to change that.

I write on a computer with a GIANT screen that's positioned so close to my face my nose practically touches it. I also use a setting that inverts the colours on my screen – so a black background with white text. This helps cut down the glare that hurts my eyes. I also work in a dark office/library we've dubbed, "the batcave."

You might notice in my books that sometimes I forget to describe what people look like, but I always have lush descriptions of scent, and the way voices sound. That's because I love smells, but I often forget what people look like :)

Many things are more difficult for me than for someone with normal vision. For example, I love to hike, but because I can't perceive depth I have to go very slowly down steep slopes. I use hiking poles to help me plot my next move.

I'm also lucky to have wonderful friends, family, and a caring husband who will read out fast-food menus or movie subtitles when I can't see them. (My husband loves to invent his own dialogue and do silly voices).

No. Not all blind people use guide dogs. Or white canes. I have enough vision that I don't need a dog to navigate the world. However, I'm a big supporter of guide dogs to help people like me have freedom and independence – a portion of the royalties from the Nevermore Bookshop Mysteries series go to support Guide Dogs New Zealand every month.

Sometimes I use a white cane as a signal to people around me that I'm blind.

Yes and no. I'm not a Braille-user. I'm able to read printed text (although I have to hold it pretty close to my face), and because my eye condition is stable, I never needed to learn Braille.

Learning to read braille by touch requires years of training – learning what the dots mean is the easy part. You have to train your fingers to be extra-sensitive and learn to use your brain in a different way.

However, one of my first jobs out of university was as a Braille transcriber. I made books, restaurant menus, conference programs, textbooks, and other documents into braille for blind and low vision New Zealanders. This job required me to learn the Braille code and be able to quickly read it by sight, although I still can't read it by feel. I still remember it today and get excited whenever I see or feel Braille when I'm out and about.