Topo Maps, what scale

[urbancowboy Junior Member Find all posts View Profile Close urbancowboy]

so what scale topo maps do you guys run with? i currently have 1:25,000 but i think that might be too small a section.

Also the digital maps you can buy from the government, the 'raster' maps, does anyone know if you can buy them individualy or do they have to be purchased as a pack of the state, NSW in my case.

PS. WTF is raster?

sorry guys i know i ask alot of questions RE: Mapping but i do look elsewhere first and you guys are good at telling it to me in plain english

[Guest Close Guest]

Topo maps come in various sizes.

1:25k is good for tight work in forests etc.
1:50k is more acceptable for normal driving work offroad.
1:250k is OK for general touring, mainly highway/backroads.
You can print these out as you need them, or buy them in map packs from good map shops.

You can buy all of Aust on 1 DVD now in 1:250k scale. Plenty of places like GPS Oz sell it, another one I highly reccomend and he will spend heaps of time chatting about it if you need is Alex at www.cartographics.com.au
CFS books in 1:50k are also a good buy.
Raster: More info here: http://www.geom.unimelb.edu.au/gisweb/G ... Raster.htm

It is basically a method of converting vectors and distances to a format accepted for mapping (Very crude description).

[Spurio Senior Member Find all posts View Profile Close Spurio]

Hidee Ho - Urbancowboy,

I don't know if anyone else on this site can answer this but I'll have a go.

I make maps and stuff. I was originally known as a cartographer but now because of all the computers, I am a GIS (geographic info system) specialist !! One of my accounts is to make programs that make your SatNAV work 'the most logical way' :lol:

I drive around the country checking maps - What a Job !!

My work is full of unusually big words that generally have a very small meaning, so if I write some thing you don't understand please ask ?

Re your scale question: Depending on what topographical detail you wish to extract from a map is which scale you require. A 1:25K is pretty good for orienteering as relief and watersheds can easily be interpreted.

Usually in 4wding (in locating track (smaller) intersections and/or waypoints) you can probably get away with a 1:50K or 1:100K within about 250kms of any coastline in Australia.

It really depends on what area you want the map for ?? Forestry trails are a bugger to keep up to date because they constantly change and regrade them every few years.

Many of the outback maps are a larger scale as there is not much detail there anyway - Oh look ANOTHER sand dune :roll:

Very basically - there are two types of digital data that can be entered into a mapping system (GIS). Raster is created using pixels (similar to a digital photo) and vector is created using lines. A raster version is generally much easier to store and more user friendly

As for civilian StatNAV - they are a good accessory in the city but companies constantly need to update errors. Note I did not say fix :roll:

Unless you have some big bucks to spend on really durable gear, I would save my money and buy a basic GPS and use hardcopy maps. The first and basic reason is if your batteries go flat or die or if you get dirt/water on your electronic gear it may become inoperable. I use a toughbook in the field as all the other laptop HDD and cooling fans choke on the dust.

As to why the e-maps are of such poor accuracy in regional Australia is primarily due to old base data, most of it is pre-electronic age and of poor quality. A recent company did a great job of making this old data look new :shock:

They got away with it because you can hide many errors in regions where the terrain creeps in an easternly direction by making the map a large scale

Hope that helps and was not do over technical ?

[Guest Close Guest]

What company are you with Spurio? Hema? or??

[Stuart Junior Member Find all posts View Profile Close Stuart]

I'm interested in this subject as well. I own an iPaq PDA and would like to run OziExplorer. The cost of maps seems to be a bit daunting thought.

I'm after some for the mid-north coast.

[Spurio Senior Member Find all posts View Profile Close Spurio]

I'd rather keep a little anonymity at the moment as it is a very small industry, but the company you mentioned does source a lot of data from where I work

[Damien Parker Advanced Member Find all posts View Profile Close Damien Parker]

I use 1:25k as my usual standard.

Its big enough for an area that you want to target, say the wattagans. Detailed enough as Spurio mentioned.

A throwback from learning navigation the Army way.

[Spurio Senior Member Find all posts View Profile Close Spurio]

Arh Damien another grunt !! The only problem in orienteering with a ex-army guy is everyone else tries to keep up with you as you go straight through everything, up the ridge down the other side, up the cliffs, through the creeks, through the blackberry and stinging nettle, etc......

As Damien has said and as a rule of thumb the 25K maps are pretty accurate at least 250-400kms inland from the coast for almost the entire eastern coast of australia. Most of this area was recorded fairly accurately post WWII, for aero navigation and most of the population live there.

A 25K topo will provide the same scale of CEP (circular error probability) all civi GPS units work at anyway, which at best is about 10-20mtrs or ~2.5%/km per reading. As for the SEP (spherical error probability) the error is about 5 times greater than you can throw a GPS unit.

The watagans is one of those forest areas I was talking abour that is constantly out of date. After the foresters run a few trucks down a minor road the remote imagery looks like its a main road, very confusing to keep up to date.

[Spurio Senior Member Find all posts View Profile Close Spurio]

Hey Stuart,

The big positive with a hardcopy map is the real lifespan or usability of it. I still use old but accurate (10+ yrs) paper maps and a compass to field truth new data. Most of the 4wd tracks Geowise in Australia have not really change that much since they were first cut.

I think you would be surprised at how old some of the base data for central australia has become.

With any digital product you need to ensure future compatibility. Even with all the metadata stds that have been brought in, this is still a major issue btn manufacturers of hardware and software, everyone likes their preferred file type.

One way to think about it is in 5-10+ years will your digital maps still be compatiable with the next generation equipment/software or will you need to keep your current unit in working condition to view your dataset ? The flip side is are you really going to be using them in 5-10+years anyway ?

I don't want to bitch on about all the problems with e-mapping products. They are a very popular product, don't get me wrong most of them are very good for the purpose they are designed and if they work for you implement them into your kit. They are very useful in the right situations such as onboard vehicle navigation.

cheers - Spurio

[Damien Parker Advanced Member Find all posts View Profile Close Damien Parker]

Arh Damien another grunt !! The only problem in orienteering with a ex-army guy is everyone else tries to keep up with you as you go straight through everything, up the ridge down the other side, up the cliffs, through the creeks, through the blackberry and stinging nettle, etc......

Whats wrong with creek crossings???

Throws the scent off for the dogs... :lol:

I can say that i have never been lost with a decent map and a compass.

Your right about the tracks in the Watagans though... Bloody logging in the areas near the camping grounds and storm damage has really stuffed up a lot of tracks in there at the moment.

I would hazard a guess and say that most coastal forest areas would be similar to this??

[Spurio Senior Member Find all posts View Profile Close Spurio]

I agree with the map and compass comment.

Unfortunately I haven't gotten up into the watagans for a couple of years but your creek crossing comment just reminded my of all the leeches, ticks and those huge 30cm earth worms that live up there.

The last I heard, National Sparks and Wildfire dept have closed down a lot of the old logging tracks ?? You may find that if trees have fallen on roads they don't wish people to use they may well leave them there until next fire season. The whole area is a mess of logging leases that soon will expire and it looks like NPWS may take them over.

The Watagans is a great place, I use to do the martinsville to Wollumbi pub track via slippery rock, over to Monkey face, back down to mt Warranblablablabalong did the track to the top (now closed ??), had lunch at one of the many picnic spots then headed over to Wollumbi pub for tea and a brew out in the grass next to the brook.

[Stuart Junior Member Find all posts View Profile Close Stuart]

Hi Spurio,

Thanks for taking the time out to write to me. I appreciate it.

The big positive with a hardcopy map is the real lifespan or usability of it.

I agree with you. However, there's a lot of positives for digital maps - mainly I can drive and not have to worry about where I am precisely. It also reduces the amount of arguements between the driver and "navigator". And the hardcopy maps don't get stuffed quite as quckly either.

I always carry topos of the areas Im going to. I've got a great collection of them. It's just nice not having to unfold one all the time

With any digital product you need to ensure future compatibility. Even with all the metadata stds that have been brought in, this is still a major issue btn manufacturers of hardware and software, everyone likes their preferred file type.

When I got my first GPS/Sat Nav device years ago, there were hardly any maps available for it. It used to cost quite a lot to get a new area as well. These days, there seems to be more and more free or cheaply available maps that can be downloaded or bought from stores. I'm thinking that if the maps are no longer compatible with new software, someone will write a converter for them, otherwise there'll be maps available for the new system with a price like the ones for the current systems.

I do agree with what you say though. And the paper maps are definately a lot more reliable (I haven't had to recharge the batteries in my Wattagans map since I bought it in 1997!).

All the best.

Stuart.

[Damien Parker Advanced Member Find all posts View Profile Close Damien Parker]

I agree with the map and compass comment.

Unfortunately I haven't gotten up into the watagans for a couple of years but your creek crossing comment just reminded my of all the leeches, ticks and those huge 30cm earth worms that live up there.

The last I heard, National Sparks and Wildfire dept have closed down a lot of the old logging tracks ?? You may find that if trees have fallen on roads they don't wish people to use they may well leave them there until next fire season. The whole area is a mess of logging leases that soon will expire and it looks like NPWS may take them over.

The Watagans is a great place, I use to do the martinsville to Wollumbi pub track via slippery rock, over to Monkey face, back down to mt Warranblablablabalong did the track to the top (now closed ??), had lunch at one of the many picnic spots then headed over to Wollumbi pub for tea and a brew out in the grass next to the brook.

You should come up for our trip next month.

It would be great to have some one with a bit more knowledge on the area with us.

The two best tracks we found were Barwicks rd which comes up over the northern side of the cleared area. Up from old/ New mill Rd which was the other track we found that was not over grown.

I know there are more up there that have a few interesting sections, its just spending the time up there to find some. Not that thats a hard thing to do, but local knowledge goes a long way.

[plucker Advanced Member Find all posts View Profile Close plucker]

In my trips to the wilderness, I have always used the 1/25k maps as a guide only. These maps give a very good indication of the terrain and creeks which will not change significantly. I have a hand held GPS that will tell me roughly where we are, but other than that just go on what the map says. Obviously sometimes there are changes to the track which you just work out when it happens.

[urbancowboy Junior Member Find all posts View Profile Close urbancowboy]

okay so it looks like i have to go with the compass and map gear, haha.

is there such a thing as a 1: 100,000 map book of NSW that anyone knows of, not really thought about it heaps as it is 1:40am...hahaha