Crossability

[Scott]

On the off chance that anybody else still cares about map specs, perhaps some kindly moderator could split the relevant stuff from the LP thread.

I notice that Aire used the "purple line" approach on the map of Attermire; this certainly (should) leave you in no doubt what can and can't be crossed, but on the downside, it completely obliterates the symbol, so if you're using the feature for navigation you don't know whether it's a wall or a fence. So I think that the ISSOM approach - uncrossable means not to be crossed, even if you can - is by far the fairest and clearest.

As the piece in Focus illustrates, the simple way around this for fences is to put the purple line on the opposite side to the tags (though admittedly walls would still be less obvious with only half a dot). I think the greater danger, as a couple of people have pointed out, is the risk of "purple saturation" in an area with a lot of deer fences or uncrossable walls. I agree that the ISSOM solution is by far the more elegant - perhaps, as quite a few folk have suggested, it's time for ISOM2000 to be revised to keep up with the developments in mapping and printing technology.

[Ed]

The problem of the purple obliterating the wall/fence/not-to-be-crossed feature only occurs when not using a "transparent" purple, usually when digital/laser printing.

The solution is simply to underprint the purple, i.e. add in an extra purple colour in OCAD (or whichever other software you're using) with a lower priority than the black which is used for the walls/fences (you may of course need to do this in the map file rather than in the course-planning file, but it's still not that tricky). You can then see what sort of feature it is, and that it is not to be crossed, and still have your course overprinted (and with all circles and lines cut appropriately so that they don't obliterate relevant features!)

edited to add that this works because the purple do-not-cross symbol is a thicker line than the wall/fence line, so you get a black line with a purple border.

[RJ]

A possibility is to duplicate the feature, eg, wall or fence in the symbol table. Then increase the size of the new symbol to, say, 150%, and change the colour to purple. Select all the fences and walls that you want to have shown as not-to-be-crossed and change them to the new symbols. That way it becomes a clearly visible non crossable boundary. A thicker, heavier purple wall symbol.

Then show the new symbols in the legend with bold text.... DO NOT CROSS EXCEPT AT MARKED CROSSING POINTS

[redpossum]

The IOF Map Commission is just beginning its revision of ISOM under the title ISOM 2010X. I'll make sure that our representative, Erik Peckett knows about these comments.

[graeme]

Two things Erik could do that would help in the UK.

1. ISSOM-style "Do not cross" walls/fences. This seems to be an English issue so BOF will need to push for it, in some countries they don't map the fences at all. If I were mapping an area with lots of uncrossible walls, I'd seriously consider using ISSOM even for a classic map (in fact, I'm converting one of ours at the moment).

2. Use of white for the predominant terrain type. At least part of the legibility problems of contours in open area is using brown on brown. For example, at this year's BOC, did we really need to colour the whole map brown to remind people there were no trees? Again, most countries where forest is the norm wont care less. I'd also like to see a return to white as "Private OOB" for street maps.

Graeme

[SJC]

At least part of the legibility problems of contours in open area is using brown on brown. For example, at this year's BOC, did we really need to colour the whole map brown to remind people there were no trees?

There have been a number of maps of open fell where the background has been faded to a paler brown than in the ISOM specification. This seems to be a much better solution than leaving the map entirely white. Mappers / planners / printers applying a bit of common sense rather than dogmatically abiding to the specs.

[redkite]

Interestingly, the old Pwll Du maps (going back to the old coal board days) had an almost white background and the contours were really clear and much better than this years BOC maps.

Only know this because SWOC had an old stock that th euniors used to use for training excercises.

[EddieH]

I ran on an old white Pwll Du map. To say that the contours were "better" is extraordinary. It is impossible to even reconcile the oland new version in several places.

[seabird]

Changing the purple transparency setting works wonders, enabling you to see the walls fence beneath the purple OOB overprint.

But you probably need to set up a second transparent purple for this. The result doesn't look right when you can see map details through control numbers, and lines and circles look better cut rather than transparent.

Having had Aire quoted as using the purple overprint for Attermire, at Valley of Desolation, where there are fewer walls and fences, we will be putting controls on all crossing points and no purple OOB overprint. One consequence is we may need to use Series 5 si cards (or whatever the one's that can take 30+ controls are called) for Course 1.

Now the plug. Valley of Desolation is an area of mixed terrain, fast rough pasture, runnable coniferous and deciduous woodland, and prediminately well burnt heather moorland (longer courses only). All in picturesque Wharfedale. Should be a good warm up for the JK.

[NeilC]

I note from the final details that the map being used for the SARUM national event next weekend has been prepared using Sprint Map symbols. Could be interesting. Presumably competitors will be forbidden to cross any double tagged fences?

[awk]

I note from the final details that the map being used for the SARUM national event next weekend has been prepared using Sprint Map symbols.

Odd. Not allowed according to the rules, and as far as I can see after a quick trawl through Map Group minutes, no dispensation in spite being a level 2 event. No axe to grind with this event, pure curiosity, especially given the shenanigans over the scale at BOC08. I would have thought this was far more fundamental.

Do agree that areas without trees should be allowed to be mapped in white. It would have certainly made Attermire, where I planned the C2 last September, a lot more readable. Equally, other open areas.

[mikey]

I note from the final details that the map being used for the SARUM national event next weekend has been prepared using Sprint Map symbols. Could be interesting. Presumably competitors will be forbidden to cross any double tagged fences?

I'd assumed it was just a typo in the final details.

[IanD]

I note from the final details that the map being used for the SARUM national event next weekend has been prepared using Sprint Map symbols. Could be interesting. Presumably competitors will be forbidden to cross any double tagged fences?

I'd assumed it was just a typo in the final details.

I asked the organiser:

This is a typo in the details they are standard O map symbols and standard event.. no funnies.