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Mapping

Show Profile  Michael Posted: 16 November 2012, 5:34 PM  
I think you've found a creepy crawly thing there Selwyn.

But there's much to be gained from advancing to v10 or v11. Have found that v11 will maintain the fit of backgrounds and the geo-referencing through rescaling rotating and moving; I don't think it did that before, or not all of it. This has significance as we want map variations of the same area at different scales from rogaines down to sprints.

Anyone else with discoveries from v11?

Show Profile  Michael Posted: 22 November 2012, 10:57 AM  
The thread about obtaining information about a map before a competition has got into discussion about specific mapping issues. I think those would be better talked about here where non-mappers can avoid them, and then others can concentrate on the difficult ethical questions over there.

Ross says 1:15000 has a different symbol size and will of course affect how the mapper interprets and draws the terrain. How so Ross? I know that mappers are TRYING to fit more stuff in all the time, but 50% bigger symbols and 50% bigger scale and nothing changes. What's your interpretation of the bit in the speci section 3.1 in bold type?

Ross says that on the current "Slump" map there are many cases where there is a distinctive tree symbol 419.0 used when it should be 420.0. Where does "should" come from Ross? The speci gives us the ability to use 418, 419 and 420 as we choose. NZ adopted conventions many years ago for the green cross and circle, for an IOF event it should suffice to give the usage in the legend?

Ross says that at some point (updating old maps) you have to start fresh. That's certainly a point worth making, I've worked on many updates where I wish I had. Certainly where the geometry is bad, in spite of OCAD's rubber-sheeting tools. If the old fieldworkers made a mess of the contours it would be worth going back to the original photogrammetry (it's all looked after carefully isn't it???) It can be worth deleting and redrawing all the vegetation because the objects relate to each other and to other features. Whether that point was reached in the case of the Slump I dunno (you said it was quite good) but certainly for maps that everyone agrees are BAD, we should start again. This is the case for many "old faithfuls" up and down the country.

Show Profile  rossmaxmo Posted: 22 November 2012, 12:11 PM  
Hi Michael,

OK, my point about symbol sizes was a bit loose, but enlarging the map (15 to 10 thou) changes things, even when the symbol sizes are also changed. The symbols increase in size, but the gaps between everything become bigger too. This leaves more room to represent more detail which is important in middle distance orienteering. Also, any inaccuracies on a 1:15000 map are magnified when it is enlarged, regardless of symbol size increasing. On a map that stems from some very old sources I'm sure there will be at least a few cases of that happening! I'm not saying that you can't have a map that can be used for both long and middle distance (1 to 15thou and 1 to 10thou), but if you are having a World Cup (middle distance only) on detailed terrain it should be mapped specifically with that in mind. For 1:10000 There should be more line contour detail representing shape and less of the point features (small knolls and depressions) that are used more in 1:15000 for graphic generalisation (this can be achieved because of the bigger gap between symbols gained in 1:10000).

With regards to the distinctive trees, I see that you are allowed to use which ever symbol you so wish. But you have 2 different tree symbols to work with, why not use them? I don't know when it became commonplace, but from my experience in Europe, the small green dot is always used for trees that have a small trunk and little canopy (such as cabbage trees) and the ring for bigger trees with a canopy. I suppose it would suffice to give the use in the legend, but by simply changing the appropriate trees to the different symbols then map will provide the reader with a lot more information.

The current Slump map is good yes, and the terrain itself is great! Being from Hawkes Bay I can certainly visualise what will be in the terrain from the map. I'm also sure that the new version will be even better. My only concern is that others might have difficulty interpreting what's going on. I think that for a World Cup, things could have been stepped up a bit. Nit-picking elite orienteers (believe me, I'm not the worst!) will scrutinise over every small flaw they can find.

Show Profile  rossmaxmo Posted: 22 November 2012, 12:25 PM  
PS. The thing about the 1:15000 Slump with different symbol sizes comes from here:
The ocad map is at 1:15,000 but the contour lines, form lines, slope lines
and dot knolls have been reduced to 80% of standard IOF line widths.
The magnetic north lines are at 250m apart as used on 1:10,000 scale
maps.
The map is set up for printing at 1:10,000 scale as it is easier to read the
contours, knolls and depressions at this scale.

Read more here:
http://www.hborienteering.com/club/history/maps/TheSlump.pdf

Show Profile  Michael Posted: 22 November 2012, 2:02 PM  
Interesting. I don't know that the increased gaps in 1:10,000 (in proportion to the increased symbols) are supposed to be filled up with extra detail are they? What do other mappers think?

Ross can you tell me where I can get the publication "From My Experience"? If we are going to follow that in NZ I'd like to have a copy:-))

HBOC 2007 version: Naughty!

(I had to rejig this after reading more carefully:-))

This message was edited by Michael on 22 November 2012, 1:14 PM

Show Profile  Paul I Posted: 22 November 2012, 2:23 PM  
You may have nits Ross?? I tend to agree with the concept and reality that in many terrain types a map prepared for a 1:15 and one for a 1:10 are two totally different beasts.
I think it's one of the main issues that need to be resolved and catered for in ISOM201X. Long and middle course requirements are so different but worldwide it looks to me that the lines are blurred too much between the two course setting styles which in turn causes problems.
However to me looking at the old Slump map and the type of terrain it is,I think you may be overly worried (admirably so) Providing of course that the line thicknesses and symbol sizes are reinstated, and since offset printing quality will allow this easily, as well as a careful and thorough remap as will be the case. I would expect if there were some point features that could be represented as contoures these would be picked up. I would think the Slump could be viewed by competitors and the IOF as an impressive model ISOM map in respect to generalization and readability. If it were to go down the path of including a lot more formlines I think the map will be too complex to run at the speeds that we will see in January. I'm sure there are areas where more detail should definately be shown, and you know the map better than me Ross, but I also think and hoping your concern is overworried about not being perfect. Maybe this comes from being such a magnificent Sprint Map specialist!
My thoughts on the trees are that the green dot potentially could get mixed up with small vegetation patches, I think if it has a small trunk and not that distinct, then leave it off anyway.
More frequent use of slope Tags could be useful on the Slump as also needed on many of our maps.
Couple of things I don't like about the outgoing ISOM that I would love to see on the new would be to distinguish between the black of rock and the manmade black of tracks and buildings. One of them could be a dark gray. Probably the rock as it might be able to be transparent to brown contour detail. I also belive that there should be large and small dot knolls and elongated knoll point symbols, amoungst other things but thats another story.
Oh yeah, the small earth bank symbol sucks out of proportion.
Great to be concerned even though it's a bit late. I'm sure it will be awesome and can't wait.

Show Profile  Paul I Posted: 22 November 2012, 2:48 PM  
Hey Ross, there again I realise that you are out the experiencing the latest developements in Europe so we mappers need to listen carefully to you and other thoughtfull elite orienteers.

Show Profile  rossmaxmo Posted: 22 November 2012, 8:00 PM  
Haha, I don't know if my experience is worth following. I think that looking at maps of reputable competitions in Europe would be a better guide

When I'm not sure about something in sprint mapping, and ISSOM is being useless, I just look at some old maps, or search some online, http://omaps.worldofo.com is great for that. It might help for 1:15000 & 1:10000 too. It would at-least make identifying any trends that emerge a bit easier - it's a shame they don't update ISOM every time someone starts to do something a certain way

I remember this race: http://www.woc2008.cz/files/images/scontent/maps/middleF/middleF_MEN.gif - a good example of a map that would be a bit of a nightmare if mapped the same way at 1:15000 and also one using both kinds of tree symbols, even in forest! - 'from my experience' just the ring is usually used for distinctive trees inside forested areas, the small dots are used more in open areas.

Show Profile  The Map Guy Posted: 22 November 2012, 9:22 PM  
I think simplification is the most important thing for orienteers - whether competing or fieldworking. The meaning of "distinctive" is that is sticks out from the rest of lesser or other species of trees. Competitors haven't got time to analyse the type of tree. To my mind a green dot would best represent something like a gorse patch. If you intend using it for the likes of a cabbage tree (essentially an aerial feature) what do you use for a gorse patch which is essentially a ground feature?

NZ flora differs dramatically from that on European terrain. If it ain't broke why "fix it"? Next you'll be trying to differentiate between a round and a rectangular water trough!

Show Profile  rossmaxmo Posted: 22 November 2012, 10:15 PM  
It should be up to the runner what they to choose to simplify from what is given to them. Gorse patches just need to be drawn as a shape symbol, but keep it misshapen, then they look a lot different from a perfectly round dot-tree.

This: http://www.cornwallpark.co.nz/UserFiles/Image/38690025.jpg

Looks a lot different from this:
http://www.allcountries.org/photos/new_zealand/cabbage_tree_harataonga_new_zealand_photo_scott_venning.jpg

I think it's more important in NZ, because a lot of our maps are in open land, and we have a great variety of flora of different sizes especially compared to Europe which is mostly thin pines. I'd prefer to have both on the map.

The water-trough analogy is a bit of a reach. In comparison to big canopy trees and small trees it's more like saying you should map a small water trough and a big water tank as the same feature.

A green ring is 12m in diameter and the dot is 7.5m, that's a big difference.

Show Profile  Paul I Posted: 23 November 2012, 1:36 AM  
Generalisation is such a controversial topic. For those who want to keep it simple and follow the IOF Map Commission guidelines and ISOM2000 with zero tolerance of straying from the rules, this has resulted in rejection of larger scale maps for middle events on a large number of high profile events, there is a discussion going on where many of the world's top mappers are claiming if they were to generalize as expected of them they would be out of work, such is the customer demand for detail. Many of the most popular world O multi-day meets can no longer get WRE status.
Hence decisions on ISOM201X appear to have stalled.

Show Profile  Alistair Posted: 23 November 2012, 8:48 AM  
http://web.entrebalizas.org/Doma/show_map.php?user=imingorance&map=174

...a better example of green dots and circles :-P

Show Profile  The Map Guy Posted: 25 November 2012, 4:07 PM  
Wow Alistair!! That map looks like it's been attacked by green measles. One wonders about the reliability of those green spots. There are so many that it is impossible to navigate using most of them. Even the Planner has restricted the control sites to obvious features that probably wouldn't normally be used on a M21A course.

The fieldworker must have had a nightmares recording them - presumably most came off aerial photography???

With boulder fields we have a specific symbol whereby we don't attempt to plot every boulder - just the "pick me" ones which stand out. Perhaps a green dotted screen would have been easier to use, such has been used on the Whakaipo Bay map where the gorse patches are so numerous it would take forever to map the small ones, yet it is possible to run through the these area with minor weaving around individual bushes.

Show Profile  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?

Show Profile  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.


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