This site is in the middle of a major expansion. It was originally designed as a resource for vision professionals who wanted to better understand how to care for patients with vision impairments. I'm now reworking the site with content for the general public — people with low vision and people who want to know more about low vision. Once that section is complete, I'll rework the section for vision professionals to better integrate with the general public section. Keep checking back to see how it's going, and if you find the content helpful please consider contributing to support the effort.
Well sure, not ‘Low Vision’, but we all have the experience of our vision being inadequate for some tasks. It’s useful to consider those situations, as it can provide insight when we have patients whose vision is inadequate for other tasks. Consider them ‘lessons in empathy’.
Too Small
There are probably a lot of (younger) readers who have never encountered one of these. It’s a microfiche reader. In the days before extensive digitisation of resources, libraries would deal with the problem of storing vast quantities of newspapers, magazines and other documents by taking very high resolution photos of them, and then storing the miniaturised slides of those photographic images, which took up only a fraction of the space.
The reason I’m showing this device is that those images were truly tiny, each page much less than a centimetre high. There was no way our eyes could see such fine detail, so we used a microfiche reader to project a highly magnified image of the slide on to a screen. This was how we dealt with encountering detail that was too small — we used a device that made it bigger.
Too Dark
Next situation. We all know this one. When what we’re looking at is too dark, we find a way to make it brighter. Lighting design is all about making sure we have adequate light in our day-to-day lives, but our standards are calibrated around normal vision.
Too Pale
This one’s not so common for most of us, but very common if you’re a historian, who often encounter faded documents. This sort of thing needs the big guns — a magnifier might help a bit, and bright light might help a bit, but what you really need is a computer that can scan the image and then enhance the contrast. This is the most effective way of dealing with a document that is too pale. We use a special device that can make it bolder.
I once attended a lecture by a world-renowned glaucoma specialist. He illustrated some of his charts with labels in yellow text on a white background. None of us could read it. I was amazed that he — an optometrist — could make such a careless design choice. Other times I’ve noticed contrast issues are ‘desktop publishing crime’ (magazines or websites in which the writer might use light print on a lighter background, or dark print on a mid-dark background). This all comes down again to careless design. An important part of inclusive design involves avoiding low contrast whenever possible, even if it looks arty/cool .
Photo Flash and
Central Loss
Up until this point, the problems have been a matter of a mismatch between stimulus and sensitivity. The illumination is lower than our retina is designed for, or the object is too small for our retinal resolution. The issue is generally solved by appropriate design — we illuminate our rooms to a certain standard, we don’t use print below a certain size. Loss of central field integrity is different though. It’s not merely a mismatch, and we can’t really design around field loss.
There are few circumstances in which we can get insight into the experience of macular field loss, but this is one most will have encountered. Afterimages from a photo flash (damn those paparazzi, they won’t leave us low vision optometrists alone!) or reflections of the sun off shiny surfaces, which then get in the way of everything we look at for a while. This is one of the few times when we get to experience having a macular scotoma, so make the most of it when it happens. Look at people’s faces, then experiment with eccentric fixation. Try reading fine print. Take note of how bloody annoying it is, and then take a moment to count your blessings that in ten minutes your scotoma will be gone, unlike your patient with AMD who has it forever.
Aside: On the evening after I (finally) published this website, my family and I went out to dinner to celebrate, and (appropriately enough) we all had an ‘insufficient vision’ experience. It was a high-end Mexican restaurant, with beautiful decor which included lamps that were in elaborate metal shades, closed at the base. Very atmospheric, but it meant that the light levels were even lower than the already-low levels you normally associate with restaurants. And the menus were printed on paper which was lovely and thick, but it was kind of a mid-brown colour, so the black print didn’t stand out well. Result — none of us could read our menus. Cue a mass appearance of mobile phones and turning on the flashlight function to get a bit of light on the page.
Every time this sort of thing happens, I think about how annoying it must be to have to do this sort of thing every place I go. But also how much more annoying it would be if we didn’t have any means of making the menus visible. As a low vision specialist, I can’t fix my patients’ vision, so I can’t take away all the annoyance and frustration in their lives. But I can still make a huge difference by helping them find appropriate devices and strategies so they can still do what they need to do.