I'm very aware of the legibility problems that affect older orienteers. Though colour discrimination degrades with age too, I don't seem to have any of the colour-blindness types. I invite comments from affected people on the following.
There's a lot of discussion about creating the best purple for digital printing. Olive green seems destined to play a bigger part in maps, with ISOM about to give it the "do not pass" meaning. The "go vs no-go" distinction would seem to be on a par with course marking in importance. I have never heard any suggestion that olive green (yellow 100% green 50%) is hard to distinguish on typical ISOM maps. Is that an oversight, or is it the "new wonder-colour"? If the latter I have some ideas for its use elsewhere. But I can't be the judge.
My Dad is red-green colour blind and can't tell the difference between olive green and the orangey-yellow that passes for clearings on most maps. This can cause major issues on sprint maps (although his grumblings usually revolve around the fact that if the yellow was actually yellow, he wouldn't have any issues).
Where we are, olive green rarely makes an appearance in ISOM maps, except the rare occasion where it is full of buildings and can be figured out by context. If olive green is used more extensively, I think his head might just explode in frustration.
As someone who has protanopia, I'd be pretty displeased. I've even had some times when the colors were a bit off and what I was expecting to be rough open was actually light green.
Here we use it extensively on (non-ISOM) Metro maps but it's been common practice over the past few years to use cross hatch instead of full colour, mainly to assist Fletch's dad.
At my work, I produce a lot of GIS / thematic maps, one of the resources I always use is the colour blind safe category suggested in the colour Brewer website which has been extremely useful over the years http://colorbrewer2.org/
Thanks all. If I have interpreted the colorbrewer tool correctly, the maximum number of distinct colourblind friendly colours is 4. I apologise for thinking that the mapping commission might have something there.
OK. I'll reveal my ulterior motive.
Australia and NZ have a convention in MTBO that off-track riding is allowed on bright yellow. (Other countries that allow off-track seem not to have addressed what riders may find, we prefer to identify those areas we have checked out and are suitable. An exception is Hungary which has used the yellows the other way round.)
While this works well in principle I have long been worried that a "go vs no-go" decision may depend on the difference between bright yellow and pale yellow. To me they are the weakest colours in the spectrum, and we are using shade differences for something important. The question is, would it be better overall, to use yellow vs olive green for this distinction?
That's long been a problem (at least in Aus) where the printing hasn't turned out right and the two yellows look the same. That's not an issue in WA because our printers are awesome and the two are very different, but that doesn't stop riders from misinterpreting both yellows as being allowable, just that one is a bit tougher to ride on.
Personally I'd prefer to keep olive as residential (or other) OOB and use some other tactic for dealing with non-rideable open land (rider education or maybe green stripe, which doesn't really get used in MTBO maps?) If olive was used for both, I'd think people may get confused as so what they were looking for on the ground.
Olive green is misused (from my perspective) since the introduction of ISSOM. Used to be that you could tell from context what it was, because it filled up the area between streets and had houses but nothing else in it. When it's used for small gardens in a sprint race, I might as well just quit before I start.
That said, a pattern (crosshatching or stripes) of olive on yellow would probably be okay.