Yeah, it's hard to say what the determinative factors were because her general visual acuity was so low that she generally needed very large fonts very up close anyway. My mom and my sister and I also have this condition and rely on magnification to varying degrees (and for various reasons— sometimes it's truly about acuity but sometimes larger sizes/bolder fonts are a clumsy way to try to make up for contrast issues). But even those of us with usable central vision generally need large fonts anyway. We're also all, for reasons I think are mostly incidental, naturally myopic (although my mom is no longer nearsighted but farsighted (with low acuity— she's legally blind)).
> Was your aunt able to read normal print besides titles?
No. Even titles, like titles of chapters in a paperback, she could likely only read with magnification. And that's if she could get enough contrast at all. At some point, screens become much easier to read than paper, even at equal sizes.
I should learn more about the precise anatomy because it's interesting, but currently I know more about the subjectivity of it than the mechanics.
> By the way, while it is true that cones are far more densely packed in the fovea, their function is color vision, not central vision. Rods are responsible for motion perception and vision in low-light environments.
There may be other factors in these inherited retinal dystrophies that affect the way their progressions affect field of view, idk. But what I said about which areas are first distorted for cone-rod dystrophies is true, and its reverse is true for rod-cone dystrophies (i.e., retinitis pigmentosa), where people with that condition lose their peripheral vision first and their field of view shrinks from the outside-in. My assumption so far has been that this corresponds to those density differences you mentioned.
> Rods are responsible for motion perception and vision in low-light environments.
I do know that much. :)
One of the features of this illness that's very prevalent for me and my sister right now is extreme light sensitivity, presumably because our eyes rely increasingly on their rods even during the daytime and even in high-light environments. One related I've written about on HN before is how the need for lower total light emission pushes both of us to high-contrast dark themes with the lowest brightness possible. OLED screens are really nice when your rods are in better shape than your cones!
One that I don't think I have is that my colorblindness has been getting worse over time. The last time I took a colorblindness test (administered by a medical professional, at my retinal specialist's office), I could hardly read any of the Ishihara plates at all. (When the doctor came in, he asked me if I only saw in black-and-white, which I found mildly irksome but very amusing. I laughed about it with my family afterwards. I do still see many colors! I just have trouble distinguishing a lot of them, too.) My sister, who was not colorblind at all when she was growing up, is now also colorblind, about as much as me based on her tests.
Yeah, it's hard to say what the determinative factors were because her general visual acuity was so low that she generally needed very large fonts very up close anyway. My mom and my sister and I also have this condition and rely on magnification to varying degrees (and for various reasons— sometimes it's truly about acuity but sometimes larger sizes/bolder fonts are a clumsy way to try to make up for contrast issues). But even those of us with usable central vision generally need large fonts anyway. We're also all, for reasons I think are mostly incidental, naturally myopic (although my mom is no longer nearsighted but farsighted (with low acuity— she's legally blind)).
> Was your aunt able to read normal print besides titles?
No. Even titles, like titles of chapters in a paperback, she could likely only read with magnification. And that's if she could get enough contrast at all. At some point, screens become much easier to read than paper, even at equal sizes.
I should learn more about the precise anatomy because it's interesting, but currently I know more about the subjectivity of it than the mechanics.
> By the way, while it is true that cones are far more densely packed in the fovea, their function is color vision, not central vision. Rods are responsible for motion perception and vision in low-light environments.
There may be other factors in these inherited retinal dystrophies that affect the way their progressions affect field of view, idk. But what I said about which areas are first distorted for cone-rod dystrophies is true, and its reverse is true for rod-cone dystrophies (i.e., retinitis pigmentosa), where people with that condition lose their peripheral vision first and their field of view shrinks from the outside-in. My assumption so far has been that this corresponds to those density differences you mentioned.
> Rods are responsible for motion perception and vision in low-light environments.
I do know that much. :)
One of the features of this illness that's very prevalent for me and my sister right now is extreme light sensitivity, presumably because our eyes rely increasingly on their rods even during the daytime and even in high-light environments. One related I've written about on HN before is how the need for lower total light emission pushes both of us to high-contrast dark themes with the lowest brightness possible. OLED screens are really nice when your rods are in better shape than your cones!
One that I don't think I have is that my colorblindness has been getting worse over time. The last time I took a colorblindness test (administered by a medical professional, at my retinal specialist's office), I could hardly read any of the Ishihara plates at all. (When the doctor came in, he asked me if I only saw in black-and-white, which I found mildly irksome but very amusing. I laughed about it with my family afterwards. I do still see many colors! I just have trouble distinguishing a lot of them, too.) My sister, who was not colorblind at all when she was growing up, is now also colorblind, about as much as me based on her tests.