MemoryMap versus Anquet

In article <[email hidden]>,

Flat Earth Society URL: said:

The Anquet version for the Lake District region 1:25,000 is cheaper
than the MemoryMap one.....which is better?

Presumably though both are equally irrelevant to the Flat Earth Society
because they depict contour lines?

Mike <URL:http://www.path.cam.ac.uk/~mrc7/>
--
o/ \\ // |\ ,_ o Mike Clark
<\__,\\ // __o | \ / /\, "A mountain climbing, cycling, skiing,
"> || _`\<,_ |__\ \> | immunology lecturer, antibody engineer and
` || (_)/ (_) | \corn computer user"

"Flat Earth Society" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

The Anquet version for the Lake District region 1:25,000 is cheaper
than the MemoryMap one.....which is better?

The problem you have is that few of us will have both packages on which to
make a comparison. I have Anquet which serves my needs pretty well. Ascent
measurement is a little dodgy though, for example if you measure a river
course fro top to bottom and then look at the info, it shows a height gain
suggesting that at some point the river ran uphill. Their technical
department are pretty good at answering queries but on putting a question on
this to them they completely ignore it. I don't know if MemoryMap have the
same issues with ascent data.

Quoted message said:

Presumably though both are equally irrelevant to the Flat Earth Society
because they depict contour lines?

Last time I looked at my paper map it had more than depictions of contour lines?

bob watkinson said:

The problem you have is that few of us will have both packages on
which to make a comparison. I have Anquet which serves my needs
pretty well.

Anquet is generally considered better for 3D landscape viewing, but MM
has better GPS support (I think).

Quoted message said:

Ascent measurement is a little dodgy though,

That's because the height grid has a relatively low resolution, each
height square is 50m wide.

Quoted message said:

for example
if you measure a river course fro top to bottom and then look at the
info, it shows a height gain suggesting that at some point the river
ran uphill.

This is due to the line crossing the low-res height grid at awkward
angles. You get the same effect when following sharp ridges or cliff
edges, any line that runs in basically the same direction as the contour
lines is prone to this effect, coastal walks for example. If the line
runs perpendicular to the contours though, it's very accurate, for
example a walk that goes straight up and down steep hillsides.

In spite of the ascent measurements typically being too high, the
low-res height grid is good enough for a really good 3D visualisation of
the terrain. Only on sharp edged ridges like Crib Goch is the low
resolution really obvious, if you look at it very closely.

Quoted message said:

Their technical department are pretty good at answering
queries but on putting a question on this to them they completely
ignore it. I don't know if MemoryMap have the same issues with ascent
data.

They probably use the same data I'd guess. Perhaps they don't answer
because they're sick of the question? It's answered in the online FAQ.
The resolution of the height grid is 50m. This is then averaged with
the surrounding pixels in order to smooth the data (which works very
well visually). I'm not certain whether it's the pixels that are
averaged or the points on the height grid. If I want the most accurate
value I tend to zoom in to the max to get it.

Because of this averaging you'll notice that most summit heights read lo
w, particularly steep sided summits or those directly next to cliffs.
Flat topped summits tend to be a lot more accurate though, and often the
high point on the height grid doesn't match the spot height on the map,
this is typical of 50k mapping where the spot heights are often not
"spot on".

Paul
--
http://www.wilderness-wales.co.uk
http://www.wildwales.fsnet.co.uk