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The Scale Question

The standard scale is 1:15,000 (apart from sprints) but debate has continued over decades as to its suitability. Related categories: Assessment, Generalisation, and Interpretation of the Spec.

MT: Paul I Posted: 2 March 2007, 12:11 PM

Yes I understand what you are saying here Michael and am quite aware that some people are still making 1:10000 maps using 1:10000 specs which is not correct, and your'e having a tough time getting heard. It took me a while to be convinced, but now I agree that generally the 1:7500 dimensions are for the good. I do have an open mind. Currently one of two paths seem to be travelled down with regard to symbol sizing. A: The rules are adheared to by some cartographers - and [with complex maps only] we get a map that really is quite messy and hard to read. or B: the cartographer completely over-rides the rules and ignors Michaels suggestions, which is getting us nowhere. It may be ironic I know but maybe if we want more consistancy we need more flexibity! Back to my example - there are probably some knolls mapped on White Lightening that could be removed,we all no sand-dune terrain is hard to get right 100%, throwing up constant questions to the mapper however, generally that will only solve a few delemmas. We are still left with many legitamate knolls of large preportion close together that have to be drawn clearly somehow. Remembering that our brains only take in information easily when the picture is clear. Back in the day before Ocad some maps were works of art, the cartographer had the ability to manipulate almost any problem to get a great, easily understood drawing. Almost all international event maps on complex terrain that I have stowed away and covered in dust still look amazing today, they are so easy to read and comprehend, and I dolbt that these maps would come close today using Ocad with no flexibity and this flat 150% enlargement rule. One of my pet hates currently experienced on some maps, and I've seen it mentioned on this forum is vegetation boundaries, where the dot size is so big and far apart that it both covers up contour detail as well as not following the edge very well, resulting in one ugly, hard to read mess. Another example of this is where the sandy ground symbol is again so large it camoflages the contours.

In some ways I would be keen to attend the Australian mapping thing at JWOC in order to get their take on the matter, but I also feel that with rocks it is far easier to chose what to leave out when many of the boulders are clearly undersized. That's where the “pick me” concept works well. We have other issues.

I'll reapeat, mostly I think the new rule works well, it is ONLY when we experience spacific problems in trying to create a coherant and pleasing-to-the-eye finished map that we need to figure out what should be allowed to happen. I definately don't believe in a free for all, but think we could do much better than present in solving some of these issues whist at the same time working as close as possible to the guidelines of ISOM 2000.

MT: Svend Posted: 2 March 2007, 3:35 PM

Paul Firstly I find it difficult to understand what you write about map scales and symbol sizes - 1:7500 symbols for a 10000 scale map ????

OCAD automatically select the correct symbol size when you atart a new map file at the 10000 scale. However, some area symbols should retain the specification for the 15000 scale (symbol 211, sandy ground is one of them, and for some maps, also stony ground).

The ISOM 2000 reads:“Where practical the same dot screens as used at 1:15000 will give the most legible map and are therefore to be preferred.”

The Australian Federations mapping page reads: “Screens retain the specification for 1:15000 maps”.

Distinct vegetation boundary 416 is often overused in forested areas. The specification reads: “very distinct vegetation boundaries within the forest”. Some mappers overlook the two words: “very distinct”. I also think this symbol should retain the 15000 scale diminsions for 10000 scale maps.

MT: Bryan Posted: 2 March 2007, 3:52 PM

Some quick comments: I prefer a more detailed map to one which is undermapped which as Paul says has an element of bingo to it.

My work is for a mapping company (Terralink) and I have worked in it for 22 years and I find the Orienteering standard of trying to gear all mapping to a 1:15000 scale as artificial and different to the rest of the Cartographic and mapping world. To me, if the symbols were geared towards a 1:10000 scale this would be more natural and conforming (and a bit easier for new people).

In the ISOM 2000 spectification section on scale and map size it says: 'Independent of scale, maps should be drawn with lines, line screens and symbol sizes as specified for the 1:15000 maps.' The operative word here is SHOULD not MUST. If care is taken and you don't go overboard (like creating a map very difficult to see the symbols) and for major events you get the ok from the IOF controller, I see no problem with using smaller symbols. We did this for WMOC 2000.

MT: Paul I Posted: 2 March 2007, 5:28 PM

Didn't intend to confuse anyone, I should not have stated 1:7500. The link here was only that the symbol sizes come out the same dimensions as a 1:7500 m but at a scale of 1:10000. What I should have said was using 1:15000 symbol set and enlarging them 150% for a 1:10000 map does not seem to work well in all cases. Correct me if I am wrong.

MT: Svend Posted: 2 March 2007, 6:58 PM

Thanks Paul for pointing out the website, very interesting. Orest Kotylo's comments on mapping certainly makes sense but it appears to be a slow process for the IOF to make changes to the mapping specification.

MT: Michael Posted: 17 March 2007, 4:16 PM

Back from some fieldwork. Low priority apprentice work as some would have it as its a remap close to a city:-)) Had time to reflect on the symbol-size debate while grappling with numerous sand-dune knolls and depressions.

I welcome creative rule-breaking, but let's be conscious of where this is leading us. Orienteering started with government maps of 1:100,000, and there has been a steady demand for increased detail. This has led us to 1:15,000 today, and its hardly surprising that there's a demand for 1:10,000. And then, after a few years, 1:7500, and so on.

Wherever we are in this process, we can find areas where things will not fit. My statement about “no smallest knoll…” should really have been expressed as “no smallest SPACING of knolls…” Occasionally you can move features (displacement is allowed) but it's limited if there are other features nearby.

Now what's wrong with moving down this track? Cost. The increased detail puts up the time required for mapping. Mapping costs are already rising as weekend volunteers are replaced by paid mappers, and our expectations of quality rise. More details means more hours in the field and on the computer. Rogainers can navigate on a 1:50,000 map, why can't we enjoy ourselves on a 1:15,000 one?

Maybe we SHOULD move down this path. The mapmaking industry would benefit after all:-)) And I'd better make an admission. I'm making a sprint map of a detailed area, and I can't do it at 1:4-5000! Further debate welcomed:-))

MT: Paul I Posted: 17 March 2007, 5:23 PM

Sorry Michael, I never once suggested that close to the city re-maps are of low priority, I merely have a personal preference for other type of mapping because I have very limited time available for mapping work. If I were a professional mapper I would prefer a variety of mapping, big, small, town, bush whatever. My inference to those type of maps being for apprentices was not said as such, but only that those type of areas are suitable training maps for apprentice mappers. I wouldn't want you to get the wrong idea.

Kevin and I, having mapped many area's here and overseas back in the late 80's, early 90's, were always defending the right to produce 1:15000 maps because this was the International norm at the time and we didn't want our elite disadvantaged. We were always up against strong opposition preferring NZ to almost go alone in making 1:10000 maps standard. Now that I have returned to orienteering and am still keen on mapping I see that 1:10000 is taking hold globally because orienteering event formats are demanding more detail on their maps. Having an open mind on this subject, I am happy with 1:10000 as my experience of mapping overseas tells me that we kiwis have always mapped at more detail, this was admired overseas and infact started a trend to follow suit. I do note however that the IOF still suggests that the standard scale for long distance orienteering should be at 1:15000, unless the area is too complex. I'm sure your sprint map will be fine, the new specs look to have some very fine tools to use. Greg's Massey University sprint map was very detailed, including each and every stair as well as some detail under canapies. The resulting map and cartography was fantastic.

The cost is another issue that needs to be addressed. It may be a quantity verses quality issue, or may be a event price issue, a sponsorship thing or whatever, but I think a map should always display its character, especially if it is technically complex. And most definately mappers such as yourself need to be paid reasonably well for your efforts or we will struggle to make any more big maps.

It would be quite interesting to know how you coped with the detailed knoll/depression sand-dune terrain you mentioned as this is one of the most difficult and controversial problems mappers still have. It would also be helpfull to have the opinions of todays elite, who experience maps overseas to compare with.

MT: Neil K Posted: 27 October 2009, 7:25 PM

Good call Paul! Bring back the IOF standard 1:15,000 to NZ.

MT: robert06 Posted: 2 November 2009, 10:12 AM

Niel have you been looking at your dads maps again?

MT: MikeW Posted: 2 November 2009, 1:18 PM

I have plenty of old UK maps at 1:20,000 - not very much detail. 1:15,000 is OK for elites but I prefer to stick to 1:10,000 because I hope most areas I O in will be technical enough to warrant it!

MT: Marquita G Posted: 2 November 2009, 3:18 PM

Why do we need one-scale-fits-all? Younger age groups with good eyesight do not need 1:7,500 maps, while half-blind old people really appreciate them. At the TONIC events this weekend course 4 and below had 1:7,500. Classes on these courses included M16, W18 and W20. They could probably cope with 1:15,000 on the same terrain, and in fact do have to cope with this at major international events like JWOC even when the terrain is very detailed. What's wrong with having different scales for different classes on the same course? A bit more work for the organisers of course but maybe something which should be done for A-grade events.

MT: Michael Posted: 26 November 2012, 10:01 PM

Paul, can you tell us which multi-day meets wanted WRE status and couldn't get it because of mapping issues?

MT: Paul I Posted: 27 November 2012, 4:41 PM

Michael, I worded it slightly wrong but there have been a multitude of rejections by the IOF for deviations from the rules. European Champs 2012 Laser printing of relays - Rejected. NZ WRE Change scale to 1:7500, not agreed, WRE withdrawn. WRE Beograd Open 2011 Serbia, requested 1:5000 for extended middle. Request denied. WRE Nationale Sud Est, FRA, request for 1:10000 long, Denied. WRE Trossacs 2010 GBR. Denied. WRE Jaettemilen 2010 DEN. Denied WRE Blodslitet 2010 NOR. Denied

Most controversial was the WOC in France where over 100 top runners and officials signed a petition against the decision to insist on 1:15000 for the long. As far as I know areas were remapped as was necessary. The IOF afterwards pronouncing the decion a success, however the general concensous with runners as it should not be necessary to run with a magnifying glass to see the map.

I am under the impression that the OO Cup in Slovinia havn't even tried to get an IOF sanctioned WRE in the kast terrain because it is too detailed. In this regard we should be avoiding using any 1:7500 map for all but the very eyesight prone age groups, at least until changes are made to ISOM. Where ISOM 201X goes is anyone's guess. There are so many issues to resolve and so many alternatives it would be hard to agree on. For example it could be a new norm to have 1:7500 for middle and 1:12500 for long as mandatory standards, leaving sizes generally as they are. This would help with current visual problems. Alternatively kick 1:15000 for touch and make 1:10000 more generalised for the long, with 1:7500 middle norm. Or allow 1:10000 to be more detailed with smaller sizing and keep 1:15000 as is, which needs to be generalised anyway. Currently our problems are stemming from too much tiny detail on some 1:10000 maps but this is a world issue not easily dealt with by more generalisation in some terrain types. Glad someone else (Map Commision) has got the job, but I wish faster progress could be made so we can all get on with it and work to more precise guidelines.

MT: Michael Posted: 14 January 2013, 1:54 PM

The dreaded scale question. Bryan, looking at the long distance map, in good light, in a rested state, with my recent prescription glasses on, I cannot read the detail round three of my controls. Sure most of it was fine but I would like all of it to be fine.

In fact I would like to propose a principle. If an area needs a certain scale for athletes in the prime of life, then it should be larger for classes 45 (say) and over. This means typically 1:10,000 for the long, and (where elites get 1:10,000 for the middle/relay) then 1:7500 or 1:6666 for oldies. And if it is felt that elites need 1:5000 for a sprint, then 1:4000. And if the mapping for the elites needs 1:4000, then 1:3000.

MT: Bryan Posted: 15 January 2013, 8:59 AM

Most maps will have small areas of almost unreadable detail. You'll find also on the 1:7500 and maybe 1:5000 for Waikawa Beach that there will probably also be some small detail that is unreadable for most people. To get any map legible requires a lot of work which is usually not done on most maps in New Zealand. 9 months ago, the Waikawa Beach map at 1:10000 was unreadable, and it required 6 months of generalisation/incremental changes before a version was created which I could read mostly. Thankfully the printing was fine enough to make the maps even clearer.

Maybe in the new specs in our submission, we could ask that a section on recommended scales for older classes (dependent on the scale the elites are using) is added.

In regard to the new draft specs, I have subsequently been informed by David Rosen that only the people who are references for the specs have been given access to the new draft specs (and Adrian Uppill of OA is one of these). There is noone in New Zealand who has been given this access. Maybe we can be asked to be given access.

MT: Paul I Posted: 6 November 2013, 7:21 PM

but I don't think anyone's listening Selwyn.

Unless there is some kind of compromise on the MC 1:15000 sway, then I believe we should consider making two versions of our most appropriate maps. A long distance version with more generalisation for a 1:15000 scale, and the status quo version 1:10000/1:7500 for middle events and the like. This goes against one of the arguments for 1:15000 of trying to keep costs down, but at the same time allows us to fit better to the IOF MC agenda more easily. It may also give us some new life to tired or over used terrain. My ultimate fantasy would be to allow for a 1:12500 scale to be used for Long Distance, as they do with Ski O. But I appear to be a lone ranger on this one I don't believe that the map scale itself is so important but legibility/levels of generalisation that still allows for detailed areas to make sense.

MT: rossmaxmo Posted: 7 November 2013, 3:34 AM

I guess eventually we'll just end up running with some kind of lightweight tablet strapped to our hand with a dynamic scale.. but still there will be the issue of deciding what level of detail needs to be shown/omitted for fast-paced orienteering - I think it should vary depending on the terrain type - I understand the need for the rules for some sort of normalization, but they can be quite restricting and for some terrain types, plain annoying. I guess as far as scale goes, I really don't mind what it is - anything is fine for me 1:3000 to 1:15000, as long as I am able to extract the important things from the map without being overwhelmed by insignificant detail whilst I'm running…

MT: Michael Posted: 7 November 2013, 1:09 PM

For sure there are fascinating terrains with lots of detail, and we seek them out and enjoy them. Equally for sure there are sub-1m “knolls” on maps and ankle-deep “depressions”. And (a bit harder to deal with) photogrammetry and Lidar with wiggles that take several minutes standing still to identify on the ground. We CAN generalise better.

But that's separate from what has happened with the ISOM revision. Nothing on the IOF website.

MT: Michael Posted: 7 November 2013, 1:22 PM

Oh I've just realised what the problem is. We've been used to using our waist (or a bit lower for tall mappers) as a quick indicator of how high/deep 1m is. With the drop-crotch baggies we trendy mappers are all wearing now, the reference level has lowered…

MT: Paul I Posted: 7 November 2013, 1:27 PM

Absolutely Michael. There are plenty of examples of over mapped areas which indeed need to be addressed, there are also examples of maps are so detailed it is impossible to conform unless you overgeneralise to the point of making the map unfair or useless to a course planner. 201x (now has a 1 in it)Doesn't seem like rocket science to me.

MT: Michael Posted: 24 April 2014, 3:25 PM

A separate issue but one which may interest followers of this thread. What symbol sizes to use when printing ISOM maps at 1:7500 or 1:5000? The std IOF scale is 1:15,000. And for those situations where they allow 1:10,000 they say the symbol sizes are 150%, ie a straight enlargement. There is no guidance for larger scales still. Do we continue to enlarge in proportion? Can make the map look a bit clunky. Do we keep them at the 1:10,000 sizes? Can make the map look spidery, and where colour areas haven't been taken right to the centre lines of roads, can leave some unintended slivers of white. Or do we do something in between? I think that the sprint symbols are generally similar to the 1:10,000 sizes (ie contours 0.21mm) so that might suggest no further increase.

MT: Paul I Posted: 24 April 2014, 8:34 PM

That's a good question Michael. I'd always presumed that a 1:7500 map was a further enlargement again from the 1:10000. But then I heard somewhere that the 150% symbol size enlargement from 1:15000 is legit on all scales. On a map I'm working on which has a rather high density of contours would most certainly require a 1:7500 print for some grades. What I presumed as the 'normal' print (200% enlargement from 1:15000) looks so so, however printing it at 1:7500 using 150% symbols (ie 1:10000) greatly improves legibility. It would be helpful to hear what others think of this. Would only require tweaking the occasional symbol such as a fenceline butting up to a new smaller gate symbol…etc.

MT: AlisterM Posted: 27 April 2014, 7:48 PM

From ISOM 2000 3.4 Enlargement of maps Where a map is enlarged to a scale of 1:10 000 or greater, all lines and symbols must be enlarged by 150%. Area screens made with fine dot percentage tints should not be enlarged wherever possible, i.e. screens at 60 l/cm.

Thus for a map scale of 1:7500 the symbol enlargement should be 150%, not 200%. eg. a small depression symbol has a width of 0.8mm on a 1:15000 scale map, and 1.2mm on both 1:10000 and 1:7500 scales.

MT: MikeB Posted: 27 April 2014, 9:52 PM

So Alistair what size should the small depression be if the map is 1:5000 as we had on the middle map. Same as 1:10000 and !:7500, 1.2mm or would they be slightly bigger say 1.6. The depressions on my map at 1:5000 are 2mm.

MT: AlisterM Posted: 27 April 2014, 10:57 PM

I'm not sure that the mapping specs anticipate that a 1:15000 scale map would be printed at 1:5000, but presumably they should still be 1.2 mm. The sprint specs width for a small depression is 0.95mm for either 1:5000 or 1:4000.

MT: Paul I Posted: 29 April 2014, 3:37 PM

Scale enlargements - Thanks Alistair that appears to confirm that the sizing of all lines and symbols for a 1:7500 map does stay at 150% (1:10000 size). Looking at a map right now printed to these specifications seems strange. It just looks like a 1:10000 map. Is it just it's not something we have been doing so is unfamiliar, or could it also give the wrong impression about the scale. One thing for sure is that it gives the map more white space and therefor easier to read. An earlier post by Michael suggests that somewhere in between could be a good solution.. I tend to agree with that, but really it looks like we are mostly doing things wrong atm. As Mike points out, what happens with 1:5000, 150% is very different looking map to what we have been used to. Roxburgh Tailings which used sprint specs as you would for a forest sprint event did look great at 1:5000.

MT: MikeB Posted: 29 April 2014, 9:24 PM

Paul I would liked to have had the 1;5000 middle map printed with those specs. It would have been much easier to read as all the symbols would have been smaller therefore much more space on the map. It almost felt like information overload and to busy with all the thickness of contour especially the Index Contours and bigger point symbols like small depressions and dot knolls. I also mistook the walk runnability as slow run and got into strife on the first leg.

MT: Michael Posted: 29 April 2014, 9:48 PM

First thanks to Alister for pointing out the oversight in my recollection of the ISOM. The words “or greater”. I will now proceed to my annual reading of the spec, and confidently expect that I will discover some previously un-noticed stuff. So there IS advice, but we are tending to want to question it.

MT: Michael Posted: 5 May 2014, 5:11 PM

The MTBO committee is working thru some questions that were raised during the carnival, and this one might benefit from other views. Often a MTBO map is largely straightforward tracks, plus a small number of places where things are very close together. Not necessarily a little “maze” though that does happen, but perhaps tracks come close together like a perimeter track on the edge of the forest just a few metres away from a public road. We might want to mark the fence between (its an obstacle) or perhaps we might want to put no-go crosses on the road. There's sometimes a limit to which we can exaggerate the tracks apart to make room. And things have to be VERY legible for riders.

One of the solutions is to use a larger scale. Between 15,000 and 10,000 the symbols enlarge so that doesn't help us, but it could help between 20-15,000, and between 10-5000. Now the 64,000-dollar question. Should we restrict ourselves to the common scales such as 20k, 15k, 10k, 7.5k etc. Or is it OK to use the biggest that will fit our std paper sizes, eg 16,500, or 9,000, whatever. To what extent do orienteers rely on a subconscious “feel” for one of a limited number of scales? Or can they be expected to adjust to any scale thrown at them?

MT: Paul I Posted: 9 September 2014, 2:55 PM

yup we are being told in no uncertain terms that we MUST generalise more, which is good to a degree, but certainly is going to make things difficult in nice detailed terrain. Pick your favourite terrain and picture it as a 1:15000 map. If this was an election issue then I'm voting for the peoples party

MT: pcbrent Posted: 10 September 2014, 2:27 PM

Anyone remember Naseby at 1:15000? was great.

MT: Paul I Posted: 10 September 2014, 2:34 PM

yeah, drawn with pre ISOM2000 they could show some of the detail as symbols were thinner/smaller. Try doing a middle race on a more generalised version now and listen to the crowd response. Plus you had good eyesight then.

MT: Michael Posted: 10 September 2014, 4:17 PM

I think you are both right. When we mapped Naseby at 1:15,000, had the middle distance even been invented?

MT: Michael Posted: 27 November 2014, 1:09 PM

Haven't got time right now, but in the age-old debate about map scales, there's some data about what people LIKE, in the form of candidates for the “course of the year” run by World of O. Anyone like to visit all the maps online and tabulate 1:15,000vs10,000 for the traditional maps, and 1:5,000vs4,000 for the sprint ones? The link is (PS There are some NZ ones there, thank you Rolf.)

And in that connection, any thoughts on what scale you would use if you were starting Naseby afresh right now?

MT: Michael Posted: 2 December 2014, 8:43 PM

What people like (as represented by the World of O course of the year entries). Of course there may be bias from whoever selected these. Maps where I couldn't see the scale excluded, but I don't think this would create bias.

Sprints. 1:5000, 4. 1:4000, 16.

Traditional. 1:15,000, 7. 1:10,000, 23.

There were also 4 at 1:7500.

MT: Michael Posted: 6 October 2015, 4:44 PM

In the goldmining areas of the Oz Champs week, the planners/controllers felt bound by the OA rules on scales - essentially stick to the IOF. Many people my age found the 1:10,000 maps hard to read. And we are not a minority - the biggest class of the carnival.

But here's another view of the scale/legibility conundrum:-))

Rolf: Posted 2 April 2017 I have seen maps where a small area of high detail is blown up to a larger scale… and shown on the side of the main map. How is this done?

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