Do You See What I See?

DDW's January Challenge Day 3: "Colour"

I've known I was colour blind since primary school (aged about 9 or 10) as I was tested at school. They don't tell you much other than you probably shouldn't consider a career as an electrician, train driver or pilot. Helpful!

What has always fascinated me about colour blindness was trying to gain an inkling of what the world looks like to those with normal colour vision. That of course is not possible, but today's challenge, 'Colour', promoted me to try and do the opposite, i.e. give those with normal colour vision a sense of what the world looks like to those with colour blindness. So:

Image 1 - Normal vision
Image 2 - How someone with Red colour blindness might see it
Image 3 - How someone with Green colour blindness might see it
Image 4 - How someone with Blue colour blindness might see it

Of course, the extent to which colour blind people people can see these colours varies from mostly to not at all. Me? Test results vary, but suggest I am moderately colour blind for both Reds & Greens. It's not as simple as doesn't see Red or Green. I see both, but not across the full spectrum (shades/hues) and of course will also struggle with any colour made up of either Red or Green, so I don't see Purple because it is a mix of blue and red and it doesn't become purple for me unless there is a lot of red, so it needs to be deep Purple before I can see it. To add to the confusion, I probably won't know that it's Purple because I struggle to identify mixed colours. This is a common issue with colour blindness, the inability to classify different shades/hues of a colour. As an example, consider Turqouise. People tell me that Turquoise is a Green colour. Are they having a laugh. Grass is Green. Turquoise cannot also be green ... can it? This site might offer some help for anyone who also struggles with this and there is an App for mobile devices called 'Colour Blend' which allows you to point your device's camera at something and it will tell you what colour it is. Not foolproof, but it's better than not having a clue which is the alternative.

As for the picture above. For me, Images 1, 2 and 3 at first glance appear to be identical. On closer inspection, I see a difference in h to k. They are different to image 1 in both images 2 & 3 but very similar to each other. Image 4 however is radically different and that's because I probably see exactly what you see as I'm not Blue colour blind. What I cannot begin to grasp is that I'm told that image 2 & 3 are as different to image 1 as image 4 is. If that is the case, you should all have blinding headaches, because that must be dazzling.