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Sprint Mapping from 2011

Good practice, issues, solutions for mainly urban mapping

This page covers from 2011, for earlier discussion, see Sprint Mapping to 2010

MT: Michael Posted: 2 February 2011, 3:59 PM

I feel the nitty gritty of sprint mapping would be better here Bryan, so that “Close to Home” can be more about formats and ideas.

Scale: the same thing is happening here as with traditional mapping - moving over the years from 25,000 - 20,000, now nominally 15,000 yet mostly printed at 1:10,000 and even 7500. I have been guilty of over-large sprint scales (Thunderball) but I will raise a voice for sticking to 4-5000. WHATEVER scale we choose there is stuff that will not fit. It is possible to generalise. We can still navigate.

A separate issue relates to older orienteers. I couldn't read a lot of the detail on the run even with specs and a thumb magnifier. With traditional mapping it is acceptable to print a 1:15,000 map at 1:10,000 for older classes. I think there may be a case for mapping “as if for 1:5000” and printing at somewhere round 1:3333.

“…there is a problem I think with the current mapping specs for bushes / gardens - I don't want to draw them as settlement olive - I want to differentiate them and I want to make them out of bounds. I mapped them as fight (and was told afterwards at the event last night I could have use 100%green 50%black instead but this also causes problems of readability when a small track goes through these areas.”

I agree and don't like olive green either! We've got dark green/black for dense/not allowed, dark green for dense/allowed, and olive green for not dense/not allowed. So I don't think flower gardens can be dark green. We need King Solomon to make some brilliant new suggestions here.

Although supposedly “not to be used in urban areas” I support your use of 507.0 the small black dashed line for small unpaved tracks. And (as discussed elsewhere) would support 506.0 for large unpaved tracks (but there probably weren't any on the area.)

MT: onemanfanclub Posted: 2 February 2011, 5:43 PM

I don't see the need for the dark green/black colour. All it seems to do is differentiate between areas you are not allowed to go through and areas you are not allowed to go through but wouldn't be able to anyway. A distinction that almost seems to condone cheating?

I think orienteers should be able to handle the idea that the same colour symbol can represent a number of things that are physically different (settlement, garden beds, crops, hedges, whatever) but all have the same “meaning” with regards to route choice - “you can't go this way!” That just leaves the question of whether olive green is the right colour symbol.

I've never struggled with it but can understand that people with different colour accuity could have issues eg, with picking small areas out from surrounding yellow. I suppose those who say they find it close to the “slow run” or “walk” greens may also have a point (to me it is quite different). But what alternatives are suggested?

MT: Bryan Posted: 3 February 2011, 8:57 AM

Looking at the sprint specifications again, I think it becomes clearer.

We have some options to map urban gardens - 1. by runnability (white, light green to dark green) 2. Impassible vegetation (100% green, 50% black) (an area of DENSE vegetation which is impassible or shall not be crossed, due to forbidden access or because it may constitute a danger to the competitor. Competitors disqualified if they go through these areas) 3. Forbidden access area (Olive: 100% yellow, 50% green). (an area with forbidden access such as a private area, a flower bed, a railway line etc. Competitors disqualified if they go through these areas)

Using these definitions, there is little I would change on the Ben Burn map - most of the fight vegetation is actually fight (eg flax bushes) and wouldn't really be damaged if a cazy orienteer wanted to go through it. What I would change would be to show the flower beds (where plants could be damaged) by olive green. I actually did this on the Central Park map.

In regards to other comments: - since running on an ACT map after running on a Steve Key map, I've been against too much generalisation and I think its always better if you can to show a feature by a shape rather than by a point symbol. - I think little would be required to change the map to make it conform to IOF sprint (1:4000 or 1:5000) - it just requries in a few places to clarify or generalise - done by just producing a print at 1:4000 and working on the areas which are too detailed - this exercise would only need to be done if a map was used for an A-level or IOF event. - checking the printing ghosting that occurred on the event map - this definitely doesn't occur on my laser printer at work which is why I didn't pick it up when I did a QA and test print after drawing was finished.

MT: Bryan Posted: 4 February 2011, 8:45 AM

The map printed for the event was A4 (I produced an A3 version which covers a bit more area) so some export and editing was done on the event map.

I think the event map has a different colour table which doesn't cut out the yellow over green.

The event map also left out the Wellington City Council requirement that the map has to show a note that the contours/curbs and building outlines were owned by them and not be used for engineering purposes.

MT: Bryan Posted: 4 February 2011, 9:22 AM

From an email to me from Michael:

“Ive got this wrong before so I proceed tentatively but… are all the symbols the right size? For example the black crosses should be 1.2mm and they seem under a mm to me.”

Yes, Michael is right - I mentioned above that the contour lines were smaller and other symbols are smaller than the standard.

This came about because of the different requirements for the mapping and not checking the symbol sizes for the export Ben Burn map from the Master map.

I'm still experimenting, it's a work in progress and I'm happy to say I'm still learning my trade after 30 years mapping especially for sprint maps.

For the area in question, I actually fieldworked at 4 different scales (1:5000 Karori Streets, 1:2500 Karori Bush and parks, 1:1000 schools and university buildings and grounds, and 1:500 for The Maze)

I also created maps at different scales as well (1:3000 Ben Burn, 1:2000 Samuel Marsden, 1:1000 Karori Normal School and The Maze offset shown on Ben Burn Map, and 1:500 (The Maze). The symbols that ended up on the Ben Burn map were symbols used for the 1:1000, 1:2000 maps - the Ben Burn map requires new symbols to conform to the IOF standard and some generalisation to get the best readibility for a 1:3000 or 1:4000 version.

I'm happy with the level of detail I've mapped - it just needs some tweaking to get the right symbol size and the right clarity for the right scale. It's an art rather than a science.

I welcome any thoughts on how to cater for all the requirements - printing from 1:500 through to 1:10000 using the same master map. Some GIS systems use pyramid capable software showing different symbols/shapes at different scales for the same feature but Ocad can't handle it.

MT: Michael Posted: 4 February 2011, 12:39 PM

I think you're under-estimating the task of making a (say) 1:4000 version Bryan. First you have to increase a lot of symbol sizes. Then with the scale change a given little courtyard with planter boxes and zig-zag concrete edges is going to have to fit onto a paper area 0.75×0.75 ie 56% of what it does now.

The simplification really ought to be done when you're fieldworking. That's behind the exhortation to fieldwork traditional maps at 1:7500. (Which I no longer do but I managed until my eyes were 55yrs old.)

I met this problem in creating the 1:20,000 map of the Wellington region that we use for MTBO and rogaines. Initially I thought I could plug in existing maps that I had, change their scale, and fiddle them a bit. A, it takes forever. B, you NEVER take out enough when you go to a smaller scale, because the default action is “leave it in”. And the “bittiness” looks terrible. I would now use a more detailed existing map as a background and redraw what I wanted, so that the default action is “leave it out”. The redrawing helps simplification as well, for example a building with a tiny nick out of the corner is re-done as a rectangle, whereas getting rid of the nick by editing is really really slow.

The “multiple requirements” issue is much wider. Might talk about it later.

MT: Michael Posted: 4 February 2011, 9:38 PM

Interesting discussion on Nopesport about an urban mapping conundrum: the bridge where you can pass underneath anywhere, not just on a defined road or path.

MT: Selwyn Posted: 6 February 2011, 1:43 PM

With respect to sprint maps, Bryan quoted the mapping specs:

“We have some options to map urban gardens - 1. by runnability (white, light green to dark green) 2. Impassible vegetation (100% green, 50% black) (an area of DENSE vegetation which is impassible or shall not be crossed, due to forbidden access or because it may constitute a danger to the competitor. Competitors disqualified if they go through these areas) 3. Forbidden access area (Olive: 100% yellow, 50% green). (an area with forbidden access such as a private area, a flower bed, a railway line etc. Competitors disqualified if they go through these areas)”

I still find this a little bit confusing, but my interpretation is that: Symbol 421.0 (100% green , 50% black) should be used only for forbidden areas that are dense vegetation or dangerous. Symbol 527.1 (100% yellow, 50% green)) is for any other area that is forbidden, presumably any place or vegetative area that on the terrain appears crossable.

I have used 421.0 in a city park map. This was close to black symbol and when printed was very hard distinguish from black, especially at running speed. I guess you could argue that the more we use these symbols as per IOF rules then the more orienteers will get used to reading them which only good for us when we compete overseas.

And I have just noticed that part of this has already been discussed on the Close to Home thread!

I think I raised this before: I still can't come to terms with the usage of urban and non-urban brown. If both are used on the same map the map looks a bit messy. Maybe IOF never thought we would combine some urban bits into non-urban maps. Every map I have run on overseas sticks with one shade of brown for all paved surfaces and possibly also for unpaved paths. The 0.07 black line defines any changes perceived on the ground.

MT: Michael Posted: 7 February 2011, 4:46 PM

Selwyn wonders if IOF didn't think we would have urban and non-urban on the same maps. Yes its pretty clear they DID, read the sections on paths and on paved areas. But I agree its very odd. Especially the lack of guidance on the shade of brown to use which can be anywhere (for urban areas) from 30% to zero. Doesn't zero percent brown look rather like runnable forest?

But Ross Morrison in discussion has said that he likes the brown sandwich tracks, they jump off the page at him. He suggests that some of us have with a lot of years of looking at black dashed lines might just be slow to adapt. That's a valid point of view.

MT: Sandgroper Posted: 5 March 2011, 3:03 AM

Just wondering what people think about the passable wall symbol in ISSOM. I'm currently mapping an urban area that has a lot of low walls from .25m to 1.0m high. The passable wall symbol at 0.35 seems just too big for these features, especially as some of them are quite close together. I am considering using the passable stone wall symbol which is only meant to be used in non-urban areas - any thoughts?

MT: Michael Posted: 6 March 2011, 6:00 PM

The rural stone wall symbol has blobs which are 0.6mm dia so if you have a problem with things close together this might be worse. You could reduce the problem with the 0.35 lines though by forgetting about walls only 25cm high.

You don't say whether these are single-sided (retaining walls) or double-sided walls. And the specification IMO is deficient in using the same symbol for them both, as a competitor I would like to know. ISOM2000 is similarly deficient although there I avoid the ambiguity by using the cliff or passable rockface for single-sided walls.

If your very low walls are single-sided, you can use 529.1 step or edge of paved area.

MT: Sandgroper Posted: 6 March 2011, 8:56 PM

Hi Michael. There are both single (see* below)and double-sided walls. I tried using a mix of passable wall and the .14 step (529.6) with the cut-off between them set at 1.0m high. I really wanted to set it lower (0.5m) but there are several places with 0.6-1.0m walls very close together, and using passable wall distorts the space between them. Displacing the passable walls to make more space then distorts other detail. Also I want to use some of these 0.6-1.0m walls as control points, which I would not be able to do if they are drawn with 529.6.

Using the stone wall gives the map more clarity. The blobs are not really a problem because they are spaced, and the lines can be cut so that they don't occur opposite each other. And I can use them as control points. I also think they are easier to read on the run than the grey passable wall symbol.

I guess I was following other discussions here (and elsewhere) about using other non-urban symbols (eg paths, paved area shadings) and thought 'why not?'.

* The single-sided walls can be distinguished from double sided ones to some extent with the use of contours, and especially form-lines (ie approx. 1m on a ISSOM map). If you use the cliff symbol, do you include tags? If not, how do competitors know that a short black line is a wall drawn with the cliff symbol? I wouldn't be expecting to find cliffs on an urban map. If there are no tags some competitors might think it is an impassable wall and take a slower route.

In the long term, I would favour ISSOM going with a thinner line and a darker grey for passable walls - say 0.3 with 60% black. I have thought of using that for my map, but I think it would be a more serious departure from the current ISSOM.

MT: Michael Posted: 6 March 2011, 10:14 PM

If I use the cliff symbol…. I was talking about ISOM maps there not sprint. Yes many of the sprint decisions spring from the choice of the thick black line for a barrier, and hence several other black symbols have had to be avoided. They've forced us into a situation where we need to distinguish, on the run, a thin line from a thick one, and perhaps subtle shades of gray, to tell whether we can pass or not. For those of us using digital printing, not good.

This place you're mapping, with lots of passable walls closer than 2.5m apart, is it some sort of maze?

MT: Michael Posted: 21 April 2012, 12:48 PM

With the perspective of time maybe mappers could discuss the national sprint map. There was a protest about missing impassable barriers - and barriers and tiny gaps can be decisive in an urban sprint.

The most interesting site was control 104. It was shown as being inside a building corner, the description actually said inside a paved area corner. If you approached from the SE or SW you arrived at what looked like a paved inside building corner but no control. It was on an upper level (one storey up) where there was a balcony and another similar paved building corner where the control was.

The mapper has explained that he separated the upper and lower levels with the “building outline” line. I've only seen this used as a border for the building symbol, not as a stand-alone barrier. In the range of line widths from easily crossed to obstacle to impassable its near the thin end (0.14mm). What do you think?

Any other interesting sprint mapping issues? I found it hard to spot olive green in very narrow building gaps (control 137). Could be my eyesight (should older sprinters get an enlarged maps as for classic orienteering?) but I saw someone younger using the olive. Two shades of brown paving. The spec says to use a darker brown for “rural” areas but somewhere I've seen a suggestion to distinguish traffic'd from traffic-free areas. Two sizes of small tree, are we going too far with detail?

MT: rossmaxmo Posted: 22 April 2012, 6:12 AM

Sound's like the course setter got the description for 104 right (you're not supposed to use building inside corner any-more, the control desc. should be describing where the control actually stands eg - see the WOC map from last year: Sounds like just a mapping issue.

The building outline symbol should definitely not be used to represent anything other than a building outline. Impassable wall or rock face (depending on what it looks like should've been used).

I haven't seen an actual map from nats sprint, only on Route Gadget so I don't know where 137 is, but as long as the olive meets the minimum width requirement, it should be OK??

Why was the map scale 1:5000? From what I can see the area used for the courses can easily fit on A4 at 1:4000 (I hope it wasn't just to fit on those fancy borders), it would have made the mapper's job a lot easier, and might have avoided a lot of this hoo-hah. Although ISSOM says you're allowed to use 1:4000 or 1:5000, you rarely see 1:5000 maps any-more, especially when the terrain is as detailed in places as at NZ champs.

I don't think the mapper can solely be blamed for these issues. The IOF controller is responsible for making sure everything is up to standard - has the IOF controller ever done a sprint course?? If not did they delegate someone with experience to field-check the map? From what I hear, the map was ready late last year?? That leaves plenty of time for revisions.

Also, from what I've heard and seen, the mapping issues make the courses more than unfair enough to invalidate. I looked at winsplits and there is a lot of time loss throughout most of the field in many grades on controls where mapping ambiguity played a part. The protest should have been upheld and the courses invalidated, especially since it was a WRE. It's nonsense to say that the first 3 weren't affected, when from looking at the splits, they were! This approach doesn't make sense anyway because the issues affect many runners and therefore everyone's world ranking points! Even if the winner lost time on the control in protest, it still affects world ranking points because their time changes in relation to other runners who get lucky or don't have a problem, and the points are based on time. I don't know what went wrong in that meeting… I hope that those in charge of making such decisions were impartial i.e. they won't be swayed by thoughts of the amount of money 'wasted' making the map, organising the event or paying to hold the WRE - or be in charge of making decisions on protests about issues that were their responsibility in the first place to avoid.

I just realised most of what I wrote belongs in another thread, but I already wrote it, so it's going here

I also read that the mapper says 'I think the printed scale of the map caused a slight problem making the line look thinner than it was shown. When i visited the site with Rob C the IOF controller and Allan the event controller it looked to me as though I had drawn it as an edge of paving symbol, as the line looked quite thin but on checking the map file that night it was indeed a building outline' This statement leads me to believe that there were some other problems, I'm only guessing here but:

1 - Sounds like the map was mapped at 1:4000 scale and then resized to 1:5000 for whatever reason without scaling the symbol sizes at the same time. The symbol sizes after printing should be the same size after printing regardless of the sprint scale - if you hold a 1:4000 scale map and a 1:5000 scale map next to each other the impassable wall symbol should be exactly the same thickness to the naked eye.

2 - The fact that upon checking the control site during the protest process, it appeared to look like an edge of paved area symbol rather than a building outline sound's a bit fishy - they should not appear to be any different at all, the symbols are basically the same, a black line 0.14mm in width (this is LESS THAN HALF the size of the minimum impassable feature size - 0.40mm). Perhaps the standard symbol set in OCAD was tampered with, to adjust symbol sizes in attempt to make things fit? - I don't know.

MT: rossmaxmo Posted: 22 April 2012, 6:20 AM

I just saw that 5m contours were used, wtf - how is this possible?? That totally goes against ISSOM. I wanted to use them at Woodford Iona Nationals last year, we applied to IOF for an exemption from ISSOM for the WRE, but it was denied. I don't see any reason at all why you would need to use 5m contours on such a flat area.

Come on people.

MT: Michael Posted: 22 April 2012, 6:49 PM

Thanks Ross, its useful to know if most big events are using 1:4000 vs 5000. In urban sprints we have to make barriers and gaps legible to the runner, and that's pretty difficult when a person can get through an 0.5m gap. I note the spec suggests that 1:5000 should be suitable for most maps though.

The olive green that I found hard to see is around control #21 on M21E. The spec doesn't give us a minimum width of a colour, only a minimum area of it. My reading of the spec is that the buildings can be as little as 0.15mm apart, so the olive could comply by area but still be hard to see IMO. Can you tell on RouteGadget which gaps are allowed/not allowed? But as I said its maybe just a senior issue.

MT: rossmaxmo Posted: 22 April 2012, 9:55 PM

Hey Michael, I took a look, it's really blurry, is it only olive green on the northern part of those 2 buildings?? It looks possibly wide enough to represent as olive, but if there's a path in there as well then it's definitely too narrow.

I think for an impassable area symbol that it needs to be at least as wide as the minimum width of any other impassable feature - 0.40mm I also try to make all area symbols this wide, it says somewhere in ISSOM that they determined that 0.40mm was the minimum size that a runner can read while running, but I think that's very age dependent! So I try to make everything that wide.

One think I discovered early on is the building sizes. If you are drawing them from an aerial photo the actual size of the building (i.e. the walls) is actually smaller than what you see from the picture (i.e. the roof outline). So you should draw them a bit smaller. I think before you draw the buildings you need to check what's in between them to determine the size, the buildings are big and obvious, the size doesn't have to be exact. As has been pointed out, mapping is not an exact science. 0.4mm for an impassable wall is 1.6m wide in real life (at 1:4000). Same goes for an impassable fence. I've yet to see an impassable fence that's more than a few centimetres wide, and if you have a lot of these sort of features close together it makes mapping very difficult - You have to move other things around to represent it clearly, or change the way you map it. Otherwise it's not suitable for sprint orienteering and should be avoided. Another thing that makes life even hard is the gradient. You may remember in nationals last year there was a poolside in Woodford school, very steep with a lot of steps. There was a lot of detail there in a small area, that would have been difficult to map if it was flat, but on a steep slpoe like that, the view you get from the birds eye leaves a really tiny area. I had a few goes at mapping it. In the end I had to map the impassable features first, and then all I could manage after that was the paved edge symbol for the small (but passable) drops. The area could be mapped really well on a smaller scale, 1:1000 perhaps. But when you have an area like that you should avoid putting controls on features within there that don't stand out when the map is printed. (here's where I'm talking about

Anyway, the runner (well at least the top elite) look at a leg and want to see where they can't go, rather than where they can, so those are the most important features to keep in mind, most of the rest is ignored!

MT: Michael Posted: 22 April 2012, 11:50 PM

Yes. No path in there, I think bushes. I agree the buildings should be shrunk a bit in cases like this, both for the roof overhang and also to make the properties of the gap clearer. I wonder if OCAD could do with a “expand/shrink object about its centroid by x%” function?

MT: Rog Posted: 6 June 2013, 11:13 AM Presentation by Helge Gisholt: Sprint map experience and representation in city urban area - Miscellaneous Challenges Map Meeting Skien, 25-May 26 2013 (via Twitter from Eva Jurenikova @evajurenikova)

To get a better understanding of content, try Google translate.

MT: Jamie Posted: 3 February 2014, 4:41 PM

Has anyone played around with the best way of mapping closed doors, or gates, that can be opened. It seems like it could be done without creating too much unfairness…thoughts? (sprint map)

MT: Michael Posted: 10 February 2014, 11:59 AM

As always Sprint The Bay was a huge amount of fun. I wish it was not so dependant on eyesight though, and I put up a couple of ideas for discussion. The first is the colour of the course markings. I wonder if the purple is optimised for a certain type of colour-blindness, and for forest orienteering. It doesn't jump off the page in a predominantly urban map for me, and I'm going to do some trials with the white shadow on the numbers. Maybe even trying complete white although every now and then we do get a bit of white on the maps:-) The other is the degree of detail that is becoming common (and of course this echoes talk about standard mapping too). But in standard mapping it is accepted that M/W45+ are entitled to a scale 50% larger than the young people, so why not for sprints?

MT: Dwayne Posted: 11 February 2014, 12:15 PM

I'm with you Michael. At AOC SummerNav on the Wednesday before STB, we had a sprint course set by Matt Ogden as an extra for anyone who thought they needed some sprint practise. He of course designed the course to be printed at 1:4000 as per the specification, but I blew it up to A4 and used 1:3000 instead. Nobody complained Also used the white framing around the control numbers, which I routinely do now on sprint maps. See the map on this link Excuse the circle cuts - they were done at 1:4000, then I didn't bother redoing them.

MT: Dwayne Posted: 11 February 2014, 12:18 PM

Sorry, direct file link is here

MT: Michael Posted: 16 March 2014, 5:45 PM

A more “here and now” question is the depiction of “down” on sprint maps with vertical walls. I think we're all using 521.1 as its thinner than 201 impassable cliff. But the main thing is that we don't use tags which of course would make the cliff impossibly thick. So what tells you “down”? The occasional slope tag somewhere else? The occasional stream? Not usually found on a school campus. The way the spec is written I can't even tell whether a “wall” actually has an up and a down side, or is a two-sided thing.

MT: Michael Posted: 5 June 2014, 10:57 AM

Take a small gap between two buildings that has a garden in it and you don't want people to cross. For argument's sake the garden is 0.6×0.25mm at map scale. A patch of olive green would be very hard to see, and there are minimum sizes of areas of colour. An impassable wall across the gap might just be legible but could look odd because it would be fatter (0.4mm) than it is long. It could also be confusing on the ground to find no wall - am I in the right place? What other solutions?

MT: Martin Posted: 5 June 2014, 11:49 AM

Try 421 Impassable vegetation, minimum width 0.4mm

MT: Greg Posted: 5 June 2014, 1:07 PM

or just follow ISSOM

2.1 Map legibility Map legibility depends on the chosen map scale and a well-chosen set of symbols as well as the application of generalisation rules. The ideal representation would be realised if every feature could be represented in true shape. Obviously, this is impossible, and an effort to draw each feature true to scale would result in a map impossible to read even with the aid of a magnifying glass. Depending on the chosen map scale, some symbols must represent features and be exaggerated in size, often far beyond the actual ground limits of the feature represented

and under 3.3 Dimensions of map symbols All features smaller than the dimensions above must be either exaggerated or omitted, depending on whether or not they are of significance to the competitor

To me its pretty clear, I wish map makers would actually read the (entire) specifications and understand them, rather than just make their own stuff up.

MT: Bryan Posted: 6 June 2014, 10:28 AM

Lots of different options: (all are part of ISSOM) - olive - impassable vegetation - temporary out of bounds (purple)

All of these could be made clearer in the field with appropriate taping especially near a control or where a possible route exists but the planner wants it out of bounds and wants to ensure that competitors don't accidentally or on purpose take that route.

Also, all options can be made clearer through exaggeration making the gap bigger but you run the risk of distorting the building shape so much that it causes more problems than it solves.

ISSOM also mentions for buildings with forbidden access that they may be just represented in a simplified manner and that areas totally contained within a building shall be mapped as being a part of the building - another option is to have just one building with no gap but this may cause navigation errors when the competitor finds the gap and can't see it on the map.

There are many ways of showing the same thing - depending on the area, some will end up fairer/clearer than others. I remember in the World Cup two different features in Wellington College (underpass tunnel and split level) each went through more than 15 different versions before the planner, controller, mapper, NZ controller and IOF SEA came up with the final compromised version that they were happy to live with.

MT: Michael Posted: 6 June 2014, 12:18 PM

Thanks for contributions. I didn't think of 421 as I thought it had an implication of dense vegetation (and re-reading it, I still think so). Didn't think of 714 either which seems to have an implication of “construction”.

Regardless of the colour, the difficulty is that we are making a sport out of tiny gaps and obstacles. A patch of full green is going to have to be exaggerated 3X to get near the minimum area of colour, a patch of olive 6X, and there's no minimum area of 50% purple but it would be one of the above.

MT: Jamie Posted: 7 June 2014, 7:18 PM

yeah impassable vegetation wouldn't be appropriate if it was passable. I would think about exaggerating the gap between buildings and using the olive green (with outlines).

MT: Jason Posted: 8 June 2014, 7:00 PM

In my experience of sprint events some of the best legs on paper are compromised in the terrain by a technically impassable feature that is impossible to map and mark clearly. Where the mapper can't resolve this the planner's final option is to redesign the course.

MT: Michael Posted: 8 September 2014, 2:25 PM

I'm partway thru a wholesale conversion of all our 1:5000-ish park maps to the sprint spec. Sometimes (well often actually) I doubt the benefits will outweigh the effort, but anyway… The issue comes up of the urban vs rural shades of brown for the paving. Where there are areas of rural character (eg bush, riverbank) you get the awkward notion of a path changing colour and sideline thickness at some arbitrary point.

Now I've always had trouble seeing the light brown/thin sideline paths particularly on a background of pale yellow. This was emphasised last week when I went training on a sprint map and I could not read the thing under a reasonable headlamp. Coincidentally I have been reading Australia's submission to the ISOM revision, and a university vision specialist comments that many people, not just the colour-blind will have problems distinguishing colours of low saturation (ie pale). I think the answer may be to use the maximum non-urban brown (50%) for everything. And the thicker non-urban sidelines. With hardly any events providing a larger sprint scale for older eyes, this seems to me to be a sensible all-round solution. Comment?

MT: MikeB Posted: 8 September 2014, 10:12 PM

I tend to agree with your comments on the paler brown as often different printers can make it look even paler. I would prefer to use the 50% wherever possible. Not sure about using the thicker paving edge symbol though. I think the thinner line still stands out enough. Although having said that most of the school sprint maps we use up here are printed off at 1:3000 maybe 1:4000 at max, so the lines look a bit thicker anyway.

MT: Paul I Posted: 10 September 2014, 2:27 PM

I prefer the current specs. The darker brown can make everything blend too much. Just make sure the light brown is printed properly. With edging, again I wouldn't use the thicker line as they be come too important and distracting. The uncrossable thick lines need to really stand out as much as possible.

MT: Michael Posted: 7 November 2014, 1:38 PM

At some stage this might need to come out from this mapping geeks thread but I'll start here. Just as it has in traditional orienteering, sprint orienteering is seeking out complex terrains. And though generalisation is still required, mappers are depicting more and more nuances of what they see on the ground. And because of the nature of urban terrain, the legibility of the tiny gap becomes an issue - is it passable or not. We talked about a case back in June. At last night's sprint there were more than a few cases of mistaken interpretation of gaps. And the 1:4000 map that was supposed to be printed on A5 was actually A4 and the scale was I guess 1:2800.

There's more than one action that can return orienteering to a route choice/navigation/running contest. Always there is generalisation and exaggeration that needs to be done, even if we mapped at 1:500. Another is the recognition (which is there in traditional orienteering) that older eyes need a larger scale (eg 1.5X). If an event has a single map edition for all ages then maybe it should be that larger scale. (How many rural events supply only a 1:15,000 map these days???) Another is that if we enjoy urban terrain with porches and steps and gaps and non-gaps, that a larger scale is required than the so-far used 5000 (almost extinct) and 4000. Comment?

MT: inghamma Posted: 7 November 2014, 3:44 PM

I agree completely with Michael. Sprint maps are becoming more and more difficult to read as mappers seem to try and put more and more, often superfluous, detail on. In my experience this seems to be a New Zealand thing, as I have seldom encountered any such problem running overseas.

The whole point of orienteering is that it is a test of map reading/interpretation, route choice and navigation. It is not a test of eyesight. Small gaps, steps etc. on sprint maps need to be emphasised so that they are clear, and many minor features should probably be omitted all together. Generalisation, generalisation…..

MT: Michael Posted: 27 November 2014, 9:41 PM

Did another sprint tonight. Sprints (in spite of their unfortunate name) could be sooo good for us oldies who keep orienteering going by our sheer numbers. As we slow up we lose that thrill of being able to outrun our navigation ability, and the need to find that knife-edge between too fast and not fast enough. We COULD get it in the more detailed mapping of the sprint spec. IF ONLY we could read the bloody maps.

When is the message going to sink in? The sprint spec is written for YOUNG people. For example the thickness of the small path symbol 507 is 0.18mm. That's the size of the symbol in the 1:15,000 traditional spec, which nobody in NZ uses any more (except for the occasional elite event). We're all on 1:10,000 now where the symbol is 0.27mm and the dash length and gaps correspondingly larger.

So for older age groups, and events with a mixture of ages, an area mapped to the sprint spec at 1:5000 should be printed at 1:3333 or so. And (although the spec suggests that 4000 should be unusual) if the area is mapped at 1:4000 it should be printed at around 1:2666. I wear glasses stronger than my prescription AND I carry a magnifier on my thumb, but I'm sick of this stop-start activity that I'm forced into. It's not orienteering.

MT: Dwayne Posted: 28 November 2014, 9:16 AM

Nice rant Michael. I totally agree - I have enough technology at the moment to compensate for compromised vision (because of my compromised speed), but “can't see” that lasting too long into the future I _always_ print my training maps at larger scale (even the sprint ones) because they are so much more fun to use.

MT: Michael Posted: 19 February 2015, 4:25 PM

Did another Blind-O last night. A far more relevant name than “sprint”.

MT: Michael Posted: 4 March 2015, 10:29 AM

Ditto. Even worse.

MT: fraser Posted: 4 March 2015, 11:07 AM

What are you actually suggesting is the problem and therefore solution?

Sounds like the local maps are not up to international standard and have too much detail making detailed areas unreadable. Or are you suggesting you would have the same problem even on international standard maps (ie ones used for World Champs or World Cups) and therefore a scale of 1:3,000 may be one solution? Or something else?

MT: Michael Posted: 5 March 2015, 10:20 AM

Thanks for the chance to re-cap Fraser. The spec representation of urban paths is unsatisfactory, at least for older eyes as the ability to discriminate pale colours decreases. Mappers are including too much detail for 1:4-5,000. Particularly for tiny gaps with and without obstacles, but also porches and balconies. And the lack of recognition that a larger scale should be used for older age groups (or everyone, if the same map is served up for all).

Some solutions: use of the stronger browns/sidelines of the rural path spec; use of the bolder dashed line symbol 506; generalisation; larger scale (at the printing stage not the mapping); generalisation; generalisation.

Going to a larger mapping scale to fit more detail in is certainly an option too, and this parallels the ongoing debate over 1:15,000/1:10,000 for standard mapping.

MT: Michael Posted: 9 February 2016, 11:17 PM

Four out of six maps at the weekend were at 1:3000 for everyone. Looks like we're in for a repeat of the 1:15,000→10,000→7500 saga. I thought the best area was the tightest one, Whitireia Poly, and I wouldn't have liked a smaller scale. But perhaps if a vet could read it, younger people could have managed 1:4 or 5000?

MT: Bryan Posted: 10 February 2016, 9:47 AM

Even at 1:3000 parts of Whitireia were hard to read - eg one area had two paths, several fences and a covered area - all within a few square metres - at 1:3000 looked impassable at first glance - probably required simplification.

I think if the area was used for a WRE/national or international event which required offset printing, a 1:4000 map could have been created but it would have required extra work to simplify/generalise more.

At the moment comparing offset versus digital printing, offset approximately about 5-10% better but I think this is changing. There was little difference between the digital prints and the offset prints for the 1:4000 Raumati map.

MT: onemanfanclub Posted: 11 February 2016, 7:07 AM

That particular spot on the Whitireia map Bryan refers to certainly generated a lot of discussion. I think it's a good example to use when we think about what to map and why. I know I'm guilty of this myself, but rather than try to squeeze in every bit of detail that is there on the ground, we need to think about what will be useful for the competitor to know. In this case, all the competitor really needed to know was that there was a passable gap between buildings, and maybe a small section of 'normal' fence or similar could have been used to indicate there was enough 'barrier' created by the fences and split level paths to slow you down relative to a completely open gap?

MT: Bryan Posted: 11 February 2016, 8:41 AM

There also was a canopy in the mix as well which was on the edge of the two paths separated by two fences. Looking in Ocad it looked fine blown up but needed a good print at final scale to confirm that it was too cluttered. Other places on other maps were similar (especially on the university maps) - at the limit of legibility.

Based on the world cup experience, if you have time, sometimes an area requires several versions before you settle on the final one. Too detailed, too generalised - what to leave in, what to leave out - almost like opposing forces battling the mapper to get the utopia - the perfect map - which is never going to happen as I could tinker with a map forever and change my mind from time to time on how best to show features.

MT: The Map Guy Posted: 11 February 2016, 12:29 PM

Sounds very much like the Eric Andrews “pick me” principle needs to be applied. Whilst Eric generally used it on rock and boulder features I often apply it to other features whilst fieldworking. The fieldworker needs to take time out, have a deep breath or two, and ask him/herself what is important to the competitor.

In cartography, a vegetation feature may have to be made a tad bigger or smaller (than actual size) to show clarity (e.g a gap). A test print at map scale should be used in preference to what is seen enlarged on a monitor.

MT: Michael Posted: 11 February 2016, 2:18 PM

There's another principle like that, in course planning. Mentally take each control out. Was it necessary?

MT: Paul I Posted: 11 February 2016, 4:52 PM

The art of graphic generalisation is slowly becoming extinct now that mappers base material is becoming finer. People often try to maintain absolute accuracy, where the old art of exploding space a little in order to achieve better clarity is still an optimal solution in many over complex/tight situations. Who cares if the gps track missed by 0.3mm

MT: Michael Posted: 13 February 2016, 1:20 PM

Another funny at Whitireia was perhaps course planning as well as cartography. There was mention in the programme about not squeezing past the water tank (as marked on the map). If I have picked the right place, the small purple blob over the gap with the water tank in it, looks just like part of the broken circle for the control code 137:-)) But still the best area IMHO.

MT: Michael Posted: 11 July 2016, 3:37 PM

The JWOC sprint map has used a very light brown road infill, perhaps even 0%. And they stand out really well. This causes me to question my preference for as dark as possible. Maybe its because there is hardly any white forest or rough open, the situations where I can't see the tracks. Comment?

MT: Bryan Posted: 13 July 2016, 11:19 AM

No preference on lighter or darker except for tracks in forest/park areas - better to show darker 'non-urban' tracks - places like Mt/Vic with steeper contours - using urban-tracks makes them very hard to read.

I do think it good to have two shades of brown to differentiate between playgrounds and concrete areas.

Notice the very strange contour shapes NE of control 17 on the M20 course where 4 contours go between two walls under a building - obviously not possible in real life - probably better to show as just a wall under the building and remove the bogus contours.

MT: fraser Posted: 13 July 2016, 4:26 PM

It looks like they have used 10% Michael. I didn't realise you could use 0% (white) for paved area - good to know - and could be worth testing.

I tried a range of options when trying to optimise the readability of all the bushes on my Hikuwai and Hawea River maps. The best result wasn't just the most contrasting colours which was surprising to me.

MT: Michael Posted: 14 July 2016, 10:22 AM

Would be good to hear more about those tests Fraser. How did you judge “best”?

MT: fraser Posted: 18 July 2016, 7:18 PM

Well I just printed out various combinations and decided what was the easiest to read. I must have discussed it and showed at least half a dozen people.

mapping/sprintgen.txt · Last modified: 12:50pm Tue 25 October 2022 by