orienteering at optimum speed isn't really about what is on the map.
I say this because a fundamental part of achieving optimum speed for large parts of a course involves ignoring or filtering much of the detail that is put on the map.
Usually there is far more detail than you really need.
example - once upon a time in the far distant dawn of time there was a squad training exercise organised on the other side of High Dam. This exercise coincided with an event. The courses had a map exchange. Attendees of the squad weekend where given their own special maps with the first part of the course. These maps were contour only.
People werea ble to navigate quickly and accurately using them. At the map exchange - to avoid any confusion with other competitors all part 2 maps were standard full detail maps. On receiving these maps about half the squaddies went awol - Too much information, they continued to move at the pace they had on the first map but they failed to filter the added mmap information, got confused, couldn't keep up with the information overload, and got lost. To take in that extra info they should have slowed down. But it was info they had done perfectly well without on the previous map.
Too much info slows you down
Way back in the same dawn of time the argument for introducing 1:15 (i'm sure I've said this before) was more about keeping the clutter off the map, preventing overmapping in order to keep maps clear and legible. The argument was that maps should always be mapped for 15, and the same cartography blown up to 10 for those whose eyesight was failing, they don't need more info, you just need thicker lines and wider spaces.
If you are an M21 (your eyesight should be fine) and couldn't read the detail on Braunton burrows, its not because the map was the wrong scale but that it was poorly produced (either due to over mapping, poor cartography or poor printing ).
Map reading is a skill and that skill is about your ability to interpret a limited amount of information in order to navigate accurately.
Sprint / Urban maps are weird.
I don't think they need to be large scale for the purposes of showing large amounts of detailed information. Urban detail is easily shown in acurate and precise detail. Urban orienteering has a much lower requirement for interpretation of the map - its all very obvious stuff. The skill in sprint orienteering is in processing (and filtering) the map information quickly enough.
I think the large scale maps simply assists ease of processing the information as quickly as possible, just as it is quicker and easier to process a larger font than it is a smaller font. (its human ergonomics, or somethign).
So large scale maps are important for sprint O, but not because they allow greater detail.
I bet if you could see inside a sprint racer's head you would see only a very small fraction of the map consciously absorbed, a few squares and lines, accurate distances and angles, not much else, the extra and minute information being largely discarded
The use of 1:15000 scale
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Re: The use of 1:15000 scale
If you could run forever ......
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Kitch - god
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Re: The use of 1:15000 scale
What a fantastic summary Kitch.
I remember running a Sluie colour coded on a brown only map. This included circles on blank bits of map (no rock features shown). I found it really easy and fast compared with the normal map.
As Tierry is the master of such navigation, and HE thinks that the French areas should be at 1:10000, why do less competent orienteers ignore his opinion?
I remember running a Sluie colour coded on a brown only map. This included circles on blank bits of map (no rock features shown). I found it really easy and fast compared with the normal map.
As Tierry is the master of such navigation, and HE thinks that the French areas should be at 1:10000, why do less competent orienteers ignore his opinion?
- EddieH
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Re: The use of 1:15000 scale
Kitch,
I completely agree with everything you say, except you chose a bad example in
Braunton Burrows. A thing which currently plagues our Championship maps is the following process.
Event 1.
1/ Use BigJon's argument to get special permission for larger scale because of highly detailed terrain.
2/ Produce map at 1:10 with level of detail appropriate for M21s at that scale.
Event 2.
1/ Get told by BOF to use 1:15 scale
2/ Reuse photoreduced version of the old map which BOF had already agree would be illegible.
It would be interesting to test whether Jon's Culbin map is usable at 1:15. I dont have the eyesight to check, but its so clear that I can cope at 1:10 without a magnifier so I reckon it would.
EddieH: I'm sure I read somewhere that Thierry is a "middle distance specialist" : in which case he's probably just trying to slow the classic runners down
I completely agree with everything you say, except you chose a bad example in
Braunton Burrows. A thing which currently plagues our Championship maps is the following process.
Event 1.
1/ Use BigJon's argument to get special permission for larger scale because of highly detailed terrain.
2/ Produce map at 1:10 with level of detail appropriate for M21s at that scale.
Event 2.
1/ Get told by BOF to use 1:15 scale
2/ Reuse photoreduced version of the old map which BOF had already agree would be illegible.
It would be interesting to test whether Jon's Culbin map is usable at 1:15. I dont have the eyesight to check, but its so clear that I can cope at 1:10 without a magnifier so I reckon it would.
EddieH: I'm sure I read somewhere that Thierry is a "middle distance specialist" : in which case he's probably just trying to slow the classic runners down
Last edited by graeme on Thu Oct 07, 2010 6:25 pm, edited 1 time in total.
WOC2024 Edinburgh
Test races at SprintScotland (Alloa/Falkirk) and Euromeeting (near Stirling).
Test races at SprintScotland (Alloa/Falkirk) and Euromeeting (near Stirling).
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graeme - god
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Re: The use of 1:15000 scale
The GB junior squad ran on Culbin West at 1:15 during their pre-JWOC camp. I seem to remember they got on OK. Perhaps they can comment?
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rocky - [nope] cartel
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Re: The use of 1:15000 scale
[quote]EddieH: I'm sure I read somewhere that Thierry is a "middle distance specialist": in which case he's probably just trying to slow the classic runners down [/quote]
He's won a not insignificant of classic distance races though - and it was that distance his quote was refering to.
He's won a not insignificant of classic distance races though - and it was that distance his quote was refering to.
- EddieH
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Re: The use of 1:15000 scale
kitch said:
So large scale maps are important for sprint O, but not because they allow greater detail
???? I disagree! There is normally much more detail on a Sprint/Urban map and that is why it has to be drawn (and surveyed) at a greater scale, and at a smaller contour interval too. This allows mappers to depict the "twiddly" bits without which course design can be compromised, and competitors then miss out on the best challenges.
NB one of the reasons given by ISSOM for the 1:5000 scale is that The amount of significant detail in urban terrain, particularly in the centre of old towns, is often much greater than in a forested terrain
- DJM
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Re: The use of 1:15000 scale
rocky wrote:The GB junior squad ran on Culbin West at 1:15 during their pre-JWOC camp. I seem to remember they got on OK. Perhaps they can comment?
Yes they did use 1:15 - i set the maps up - and they seemed to get on OK but they were on Culbin West, which is not as complex as Culbin East
Routegadget for Culbin West event June 2010
Routegadget for Culbin East event March 2009
graeme wrote:It would be interesting to test whether Jon's Culbin map is usable at 1:15.
No i don't think so - because although it is mapped at 1:10, the symbols & lines weren't blown up by 50% from the ISOM specs (maybe by 20%?), so when you got to a bit like this:
you would either have to go with smaller than ISOM symbol sizes (which is what the JWOC squaddies did - OK for a training event but probably not viable in a championships), or have all the brown lines and dots running together...
(or just map it as broken ground, or accept that Culbin is "not suitable for international foot-orienteering" )
edit: and it's no use just saying "simplify" - the knolls in the extract above are all at least transit van sized - if you start leaving them off in some areas then the map becomes inconsistent...
Last edited by greywolf on Thu Oct 07, 2010 7:36 pm, edited 1 time in total.
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greywolf - addict
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Re: The use of 1:15000 scale
Hasn't total awareness something to do with good orienteering; being aware, without slowing down, that something relatively small that you pass is on the map, but not necessarily relying or even expecting to to see it because you haven't got time to slow down to make sure, and you know you will pick up something bigger as per plan.
When I'm orienteering well (happens occasionally ) I 'see' (ground to map) the smaller things because I know exactly where I am, and I am in 'continuous contact' with the map (like Thierry seems to be in his vidoes). However, if a feature is so small that it needs to be greatly exaggerated in size to be represented, and is likely to distort surrounding larger features, I am likely to be misled.
Yes, the top orienteers 'filter out' extraneous detail, but, somehow, I think they're more likely to be aware of everything that might be relevant to assist their assurance of exactly where they are at any given moment than are lesser exponents.
I get the impression from his videos that Thierry's 'micro route choice' is optimal because of his 'total map detail awareness'
Density of detail does not seem to slow down the best orienteers provided it is represented clearly (large) enough on the map. Proof, for me, of this was watching GG 'flow' round the 4.2km, 250m, 29 control course on on my 1:2500 1.25 m vi Wheal Florence map in 24.59.
When I'm orienteering well (happens occasionally ) I 'see' (ground to map) the smaller things because I know exactly where I am, and I am in 'continuous contact' with the map (like Thierry seems to be in his vidoes). However, if a feature is so small that it needs to be greatly exaggerated in size to be represented, and is likely to distort surrounding larger features, I am likely to be misled.
Yes, the top orienteers 'filter out' extraneous detail, but, somehow, I think they're more likely to be aware of everything that might be relevant to assist their assurance of exactly where they are at any given moment than are lesser exponents.
I get the impression from his videos that Thierry's 'micro route choice' is optimal because of his 'total map detail awareness'
Density of detail does not seem to slow down the best orienteers provided it is represented clearly (large) enough on the map. Proof, for me, of this was watching GG 'flow' round the 4.2km, 250m, 29 control course on on my 1:2500 1.25 m vi Wheal Florence map in 24.59.
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Re: The use of 1:15000 scale
I'm not sure I entirely agree with the sentiment that mappers clog up maps. The problem they have is that between controls less detail is generally needed whilst within the circle more detail may well be appreciated. However the mapper does not know exactly where the controls will be so tries to achieve a level of consistency knowing that he risks being berated for being over detailed by some competitors or moaned at by others because the detail they felt they needed at some point was missing. [Of course one of the beauties of mapping in East Anglia is if you can find any detail you tend to get commended... now where did I put my shovel].
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Red Adder - brown
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Re: The use of 1:15000 scale
DJM wrote:NB one of the reasons given by ISSOM for the 1:5000 scale is that The amount of significant detail in urban terrain, particularly in the centre of old towns, is often much greater than in a forested terrain
If that is the case (and I've no reason to dispute it), then surely the logical extension of that is that when faced with more complex 'forested' terrain, 1:10k is more suitable than 1:15k. I know the IOF say that if the terrain needs 1:10k mapping, then it's not suitable, So, are they actually saying that some terrain is too complex to use for orienteering? Or are they saying that they want to put an upper limit on the technical difficulty in long distance events? Either way, I find it somewhat difficult to comprehend.
Last edited by awk on Thu Oct 07, 2010 9:40 pm, edited 1 time in total.
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awk - god
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Re: The use of 1:15000 scale
To clarify my earlier post - I believe that MOST areas used for long distance races can and SHOULD be mapped at 1:15,000, however I also believe that some, a few areas cannot be properly mapped at 1:15,000 because they contain so many significant features so close together that they cannot be clearly shown using ISOM specifications. These are usually man-made areas - eg quarrying/old mining or sand-dunes. Culbin has been mentioned a few times. I tried reducing the scale to 1:15,000 using ISOM thickness lines - the map became a brown smear in large areas. I estimated we would lose approximately 40% of the possible control sites because the only way to show features was with the broken ground symbol. I'll try to dig out some sample areas - can't remember ifI kept these files - but I have no idea how to get a nice little map segment as in one of the posts above - any advice?
- Big Jon
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Re: The use of 1:15000 scale
i think the main problem is, that we are able to map every cm of a terrain. with laserscanning we will get maps like this:
ive found an interessting site on this problem:
http://lazarus.elte.hu/mc/ik/ohp03.htm
otherwise i think that 1:10000 will not be the solution. where more place is, we can map more things, we need a bigger scale, we have more place on the map;)
ive found an interessting site on this problem:
Reducing the terrain to a scale of 1:15 000 requires generalization, for instance: leaving out small features such as very small knolls and clearings or having to exaggerate the widths of paths or size of pits.
It is easier to map all detail however small, but this is wrong, this will often result in an illegible map.
http://lazarus.elte.hu/mc/ik/ohp03.htm
otherwise i think that 1:10000 will not be the solution. where more place is, we can map more things, we need a bigger scale, we have more place on the map;)
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moritzol - string
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Re: The use of 1:15000 scale
Moritzol - I don't think you have read my posts properly - I agree that most areas can & should be mapped at 1:15,000, but a small minority of areas have such a density of prominent features that they cannot be mapped adequately at 1:15,000. For example in some sand-dunes it is not possible to generalise except by using broken ground which then becomes unusable for control sites. When the features that are being "generalised" are 2-3m tall distinct knolls on a flat, smooth forest floor it isn't possible to map some and not others - they are all prominent and all or none need to be mapped.
Let me repeat, I am not against 15k mapping for the vast majority of long distance races, just against the blind imposition of one scale regardless of the physical reality of a particular area (especially when the decision is taken without any attempt at a field visit).
Let me repeat, I am not against 15k mapping for the vast majority of long distance races, just against the blind imposition of one scale regardless of the physical reality of a particular area (especially when the decision is taken without any attempt at a field visit).
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Re: The use of 1:15000 scale
We have been here before - have a read of The Harveys' mapping textbook. Lots of dire warnings about overmapping there. Perhaps this is driven by a desire to have more control sites on uniform English terrain? I was once told to map micro knolls and mini depressions once for this reason.
Around the mid to late 1970s we were bamboozled with multiple runability screens and complex maps. Then there was a backlash and maps became simple again. Legibility increased due to scribing.
The 1976 WOC maps were a legible Darnaway at 1:20K and a more than legible Culbin at 1:15k. Both things of beauty. That is what we should be aiming at - with the proviso of producing large print versions for some age classes - not mapping at 1:10k but blowing up the existing 1:15k maps.
Around the mid to late 1970s we were bamboozled with multiple runability screens and complex maps. Then there was a backlash and maps became simple again. Legibility increased due to scribing.
The 1976 WOC maps were a legible Darnaway at 1:20K and a more than legible Culbin at 1:15k. Both things of beauty. That is what we should be aiming at - with the proviso of producing large print versions for some age classes - not mapping at 1:10k but blowing up the existing 1:15k maps.
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Excuse me, can you tell me where I am?
Excuse me, can you tell me where I am?
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ryeland of doom - blue
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Re: The use of 1:15000 scale
The 1976 WOC maps were a legible Darnaway at 1:20K and a more than legible Culbin at 1:15k.
I don't think that anyone is saying that you can't produce perfectly legible maps at the scales you state. Just that in doing so you have to generalise to such an extent that some parts of the area then become unusable for control sites. It then comes down to a matter of opinion which approach you prefer.
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