Foinaven a Munro ?

"Duncan Gray" <[email hidden]> wrote

Quoted message said:

The announcement below is for:

The minority who are on the edge of their seats waiting to hear
The majority who may be mildly interested
The even bigger majority who couldn't care less

Quoted message said:

CMCR Ltd. of Larbert and The Munro Society will be holding a joint Press

Conference to announce the true height of Foinaven. The new height has
been
ratified by the Ordnance Survey.

This will take place on Friday 8th June 2007 at 10.30am in the Falkirk
Golf Club.

Hmm, I think the sea level at Newlyn has changed by about a foot since
records began, plus how on earth do you level to Foinaven without making the
slightest mistake? Do the GPS boffins (not me guv) know if it is possible to
level accurately and compare to the different model used in Trad levelling?
I'd like to know HOW they can be so damn sure that a mountain top is 3000ft!

I'd hate to be the guy at OSHQ that had to announce it was 2999ft 4.5ins :-)

Graham

In message <[email hidden]>, Graham Seed
<[email hidden]> writes

Quoted message said:

"Duncan Gray" <[email hidden]> wrote

Quoted message said:

The announcement below is for:

The minority who are on the edge of their seats waiting to hear
The majority who may be mildly interested
The even bigger majority who couldn't care less

Quoted message said:

CMCR Ltd. of Larbert and The Munro Society will be holding a joint Press

Conference to announce the true height of Foinaven. The new height has
been
ratified by the Ordnance Survey.

This will take place on Friday 8th June 2007 at 10.30am in the Falkirk
Golf Club.

Hmm, I think the sea level at Newlyn has changed by about a foot since
records began, plus how on earth do you level to Foinaven without making the
slightest mistake? Do the GPS boffins (not me guv) know if it is possible to
level accurately and compare to the different model used in Trad levelling?
I'd like to know HOW they can be so damn sure that a mountain top is 3000ft!

They claim their measurements are accurate to 30mm.

Quoted message said:

I'd hate to be the guy at OSHQ that had to announce it was 2999ft 4.5ins :-)

Quoted message said:

Graham

--
Chris Townsend

http://www.auchnarrow.demon.co.uk

Chris Townsend said:

In message <[email hidden]>, Graham Seed
<[email hidden]> writes

Quoted message said:

"Duncan Gray" <[email hidden]> wrote

Quoted message said:

The announcement below is for:

The minority who are on the edge of their seats waiting to hear
The majority who may be mildly interested
The even bigger majority who couldn't care less

I've already ticked it so no problem. But one day I'd like to go back
and have a go at the southern end, probably taking in Arkle so I will
probably not have any problems from M****o baggers. :-)

Quoted message said:

Quoted message said:

Quoted message said:

> CMCR Ltd. of Larbert and The Munro Society will be holding a joint Press
Conference to announce the true height of Foinaven. The new height has
been
ratified by the Ordnance Survey.

This will take place on Friday 8th June 2007 at 10.30am in the Falkirk
Golf Club.

Hmm, I think the sea level at Newlyn has changed by about a foot since
records began, plus how on earth do you level to Foinaven without making the
slightest mistake? Do the GPS boffins (not me guv) know if it is possible to
level accurately and compare to the different model used in Trad levelling?
I'd like to know HOW they can be so damn sure that a mountain top is 3000ft!

They claim their measurements are accurate to 30mm.

That's pretty good [1] given the fact they have to level in from some
way off. Where is the nearest OS benchmark?

Somewhere on the road http://www.bench-marks.org.uk/line374

Laxford Bridge to Durness

Third geodetic levelling, Scotland.
Geodetic line G364.
Levelling Route (sic)
FBM Laxford Bridge. 50.8707ft NC 2358 4673
BOLT OSBM Bolt in rock - NC 2282 4756
BOLT OSBM Bolt in rock - NC 2340 4885
BOLT OSBM Bolt in rock - NC 2389 5014
BOLT OSBM Bolt in rock - NC 2464 5114
G1941 Rhiconich. - NC 2553 5237
BOLT OSBM Bolt in rock - NC 2659 5293
BOLT OSBM Bolt on Clach A Bhoineid Bonnet Stone, NW side of road
- NC 2750 5409
BOLT OSBM Bolt on bridge parapet - NC 2848 5482
BOLT OSBM Bolt - NC 2919 5556
BOLT OSBM Bolt in rock - NC 2976 5602
BOLT OSBM Bolt in rock - NC 3098 5703
BOLT OSBM Bolt in rock - NC 3191 5800
BOLT OSBM Bolt on culvert - NC 3299 5903
BOLT OSBM Bolt on culvert - NC 3448 5971
BOLT OSBM Bolt in rock - NC 3574 6019
BOLT OSBM Bolt on culvert - NC 3645 6158
BOLT OSBM Bolt on culvert - NC 3718 6299
BOLT OSBM Bolt in rock - NC 3784 6429
BOLT OSBM Bolt on culvert - NC 3843 6562
BOLT OSBM Bolt on culvert - NC 3927 6692
G1943 NE face, 11' from E angle of house, NW side of road
- NC 4028 6767
BOLT OSBM Bolt on culvert - NC 4045 6700
BOLT OSBM Bolt on culvert - NC 4183 6711
BOLT OSBM Bolt on culvert - NC 4276 6605
FBM Durness. 191.4611ft NC 4385 6570

Quoted message said:

Quoted message said:

I'd hate to be the guy at OSHQ that had to announce it was 2999ft 4.5ins :-)

Indeed.

[1] I originally typed preposterous, but then I thought it /might/ be
possible to get that accurate if you keep the sights short and mark
all the staff points with a peg or bolts to enable checking. It's a
long time since I did any leveling and I can't remember how accurate
you are supposed to be.
--
Phil Cook, last hill: Angletarn Pikes via Beda Fell.

"Chris Townsend" <[email hidden]> wrote

Quoted message said:

They claim their measurements are accurate to 30mm.

Quoted message said:

I'm not saying it can't be done, and I imagine GPS technologies must be
behind any confident new heights. It would be no good having 30mm accuracy
with GPS if there wasn't a way of transforming that accuracy to the Geoid
model used for levelling though - unless the Geoid and Spheroid models used
for the different calculations conform to each other by less than the one
foot accuracy required to work out Munro status - I don't know......

Tongue in Cheek really. Bidean Druim nan Ramh is more worthy of a visit than
90% of Munros.......<darfc>

Graham

In message <[email hidden]>, Phil Cook
<[email hidden]> writes

Quoted message said:

Chris Townsend said:

In message <[email hidden]>, Graham Seed
<[email hidden]> writes

Quoted message said:

"Duncan Gray" <[email hidden]> wrote
> The announcement below is for:
>
> The minority who are on the edge of their seats waiting to hear
> The majority who may be mildly interested
> The even bigger majority who couldn't care less

I've already ticked it so no problem. But one day I'd like to go back
and have a go at the southern end, probably taking in Arkle so I will
probably not have any problems from M****o baggers. :-)

Quoted message said:

Quoted message said:

> > CMCR Ltd. of Larbert and The Munro Society will be holding a joint Press
> Conference to announce the true height of Foinaven. The new height has
> been
> ratified by the Ordnance Survey.
>
> This will take place on Friday 8th June 2007 at 10.30am in the Falkirk
> Golf Club.
Hmm, I think the sea level at Newlyn has changed by about a foot since
records began, plus how on earth do you level to Foinaven without making the
slightest mistake? Do the GPS boffins (not me guv) know if it is possible to
level accurately and compare to the different model used in Trad levelling?
I'd like to know HOW they can be so damn sure that a mountain top is 3000ft!

They claim their measurements are accurate to 30mm.

That's pretty good [1] given the fact they have to level in from some
way off. Where is the nearest OS benchmark?

They're using OS coastal stations as well.

Quoted message said:

Somewhere on the road http://www.bench-marks.org.uk/line374

Laxford Bridge to Durness

Third geodetic levelling, Scotland.
Geodetic line G364.
Levelling Route (sic)
FBM Laxford Bridge. 50.8707ft NC 2358 4673
BOLT OSBM Bolt in rock - NC 2282 4756
BOLT OSBM Bolt in rock - NC 2340 4885
BOLT OSBM Bolt in rock - NC 2389 5014
BOLT OSBM Bolt in rock - NC 2464 5114
G1941 Rhiconich. - NC 2553 5237
BOLT OSBM Bolt in rock - NC 2659 5293
BOLT OSBM Bolt on Clach A Bhoineid Bonnet Stone, NW side of road
- NC 2750 5409
BOLT OSBM Bolt on bridge parapet - NC 2848 5482
BOLT OSBM Bolt - NC 2919 5556
BOLT OSBM Bolt in rock - NC 2976 5602
BOLT OSBM Bolt in rock - NC 3098 5703
BOLT OSBM Bolt in rock - NC 3191 5800
BOLT OSBM Bolt on culvert - NC 3299 5903
BOLT OSBM Bolt on culvert - NC 3448 5971
BOLT OSBM Bolt in rock - NC 3574 6019
BOLT OSBM Bolt on culvert - NC 3645 6158
BOLT OSBM Bolt on culvert - NC 3718 6299
BOLT OSBM Bolt in rock - NC 3784 6429
BOLT OSBM Bolt on culvert - NC 3843 6562
BOLT OSBM Bolt on culvert - NC 3927 6692
G1943 NE face, 11' from E angle of house, NW side of road
- NC 4028 6767
BOLT OSBM Bolt on culvert - NC 4045 6700
BOLT OSBM Bolt on culvert - NC 4183 6711
BOLT OSBM Bolt on culvert - NC 4276 6605
FBM Durness. 191.4611ft NC 4385 6570

Quoted message said:

Quoted message said:

I'd hate to be the guy at OSHQ that had to announce it was 2999ft 4.5ins :-)

Indeed.

[1] I originally typed preposterous, but then I thought it /might/ be
possible to get that accurate if you keep the sights short and mark
all the staff points with a peg or bolts to enable checking. It's a
long time since I did any leveling and I can't remember how accurate
you are supposed to be.

They reckon they need an hour to do the measurements.

--
Chris Townsend

http://www.auchnarrow.demon.co.uk

Chris Townsend said:

In message <[email hidden]>, Phil Cook
<[email hidden]> writes

Quoted message said:

Chris Townsend wrote:

Quoted message said:

Quoted message said:

Quoted message said:

They claim their measurements are accurate to 30mm.

That's pretty good [1] given the fact they have to level in from some
way off. Where is the nearest OS benchmark?

They're using OS coastal stations as well.

Quoted message said:

Somewhere on the road http://www.bench-marks.org.uk/line374

Laxford Bridge to Durness

Third geodetic levelling, Scotland.
Geodetic line G364.
Levelling Route (sic)
FBM Laxford Bridge. 50.8707ft NC 2358 4673
BOLT OSBM Bolt in rock - NC 2282 4756
BOLT OSBM Bolt in rock - NC 2340 4885

etc etc.

Quoted message said:

Quoted message said:

FBM Durness. 191.4611ft NC 4385 6570

Quoted message said:

>I'd hate to be the guy at OSHQ that had to announce it was 2999ft 4.5ins :-)

Indeed.

[1] I originally typed preposterous, but then I thought it /might/ be
possible to get that accurate if you keep the sights short and mark
all the staff points with a peg or bolts to enable checking. It's a
long time since I did any leveling and I can't remember how accurate
you are supposed to be.

They reckon they need an hour to do the measurements.

That is possible if you are being really careful and making several
measurements at each point. The question is how many sights did it
take them to level in?

From CMCR's website at http://www.cmcr.biz/news.htm#munro

Media Announcement

Following the successful measurement of Foinaven on 12th May 2007,
there will be a media announcement of the result on Friday 8th June
2007 at 10:30hrs which will take place at the Falkirk Golf Club,
Carmuirs, 136 Stirling Road, Camelon, Falkirk, FK2 7YP. Please refer
to www.falkirkgolfclub.co.uk for a location map.

Following the media announcement the result will appear on our
website.

Beinn Dearg will be measured on 25th August 2007.

--
Phil Cook, last hill: Angletarn Pikes via Beda Fell.

The message <[email hidden]>
from "Duncan Gray" <[email hidden]> contains these words:

Quoted message said:

CMCR Ltd. of Larbert and The Munro Society will be holding a joint Press
Conference to announce the true height of Foinaven. The new height has been
ratified by the Ordnance Survey.

Quoted message said:

This will take place on Friday 8th June 2007 at 10.30am in the Falkirk Golf
Club.

Any campsites up that way or will I have to camp by the side of the road
and incur the anger of Bloody Angus?

--
Roger Chapman
Nearest Marilyn still to be visited - Great Orme.
89 miles as the crow flies,
considerably more as the walker drives.

"Phil Cook" <[email hidden]> wrote

Quoted message said:

Quoted message said:

They reckon they need an hour to do the measurements.

That is possible if you are being really careful and making several
measurements at each point. The question is how many sights did it
take them to level in?

I guess gps will be used to check existing levelling. A local transformation
between models should be good enough to confirm heights. My original point
was though: how do they know the local FBMs are good? (as in: how good was
the absolute accuracy of Scottish trigs when checked with gps?)

Graham

Graham Seed said:

"Phil Cook" <[email hidden]> wrote

Quoted message said:

Quoted message said:

They reckon they need an hour to do the measurements.

That is possible if you are being really careful and making several
measurements at each point. The question is how many sights did it
take them to level in?

I guess gps will be used to check existing levelling. A local transformation
between models should be good enough to confirm heights. My original point
was though: how do they know the local FBMs are good? (as in: how good was
the absolute accuracy of Scottish trigs when checked with gps?)

Reading around
http://www.gmat.unsw.edu.au/snap/gps/gps_survey/chap11/11310.htm
I have found that GPS is as good as leveling over these kind of
distances. It being particularly useful for checking traditional
leveling for Mk I b***s ups.
--
Phil Cook, last hill: Angletarn Pikes via Beda Fell.

The message <[email hidden]>
from "Graham Seed" <[email hidden]> contains these words:

Quoted message said:

Hmm, I think the sea level at Newlyn has changed by about a foot since
records began,

Newlyn being in the South is presumably sinking but ISTR that the
original datum was at Liverpool and was about 1 foot different to
Newlyn. So is the difference now 2 foot or zero?

Quoted message said:

plus how on earth do you level to Foinaven without making the
slightest mistake? Do the GPS boffins (not me guv) know if it is
possible to
level accurately and compare to the different model used in Trad levelling?
I'd like to know HOW they can be so damn sure that a mountain top is 3000ft!

Surely MSL is now a theoretical surface above which the height of a gps
can be measured to the limit of accuracy of the gps?

--
Roger Chapman
Nearest Marilyn still to be visited - Great Orme.
89 miles as the crow flies,
considerably more as the walker drives.

"Roger" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

The message <[email hidden]>
from "Graham Seed" <[email hidden]> contains these words:

Quoted message said:

Hmm, I think the sea level at Newlyn has changed by about a foot since
records began,

Newlyn being in the South is presumably sinking but ISTR that the
original datum was at Liverpool and was about 1 foot different to
Newlyn. So is the difference now 2 foot or zero?

Apparently original Newlyn datum will always be used for heighting (I read
that somewhere, can't quote the source). There are a lot of 'what ifs' in
the surveying world so I just chucked the fact in that the sea is rising to
create debate :-) It will probably rise quicker what with global
warming......
I think Liverpool was rejected in favour of Newlyn because Newlyn was
regarded as a better datum in that it was nearer to the Atlantic and didn't
have local influences mucking up the avererages of high and low water.
However, I suppose Liverpool can be used as a check as can any tidal station
(for gross error). Hell, if they had the cheek to say Everest was 29028ft I
suppose we can claim to know if a mountain is >3000ft.

Quoted message said:

Quoted message said:

plus how on earth do you level to Foinaven without making the
slightest mistake? Do the GPS boffins (not me guv) know if it is
possible to
level accurately and compare to the different model used in Trad
levelling?
I'd like to know HOW they can be so damn sure that a mountain top is
3000ft!

Surely MSL is now a theoretical surface above which the height of a gps
can be measured to the limit of accuracy of the gps?

Not that I'm an expert on this, but GPS heights are worked out using a
spheroid model and Levels are worked out using a geoid model - how similar
these are for a relatively 'flat' part of the world I don't know - i was
kind of hoping Dominic or someone would chip in here.

Graham

In article <[email hidden]>, Graham Seed
<[email hidden]> writes

Quoted message said:

Not that I'm an expert on this, but GPS heights are worked out using a
spheroid model and Levels are worked out using a geoid model - how similar
these are for a relatively 'flat' part of the world I don't know - i was
kind of hoping Dominic or someone would chip in here.

I was tempted to join in earlier but needed to engage my brain first.

Essentially you are correct about the difference between GPS and
levelling techniques. However your kind colleagues at the OS have
created a model of the Geoid for the UK - National Geoid Model OSGM02
which effectively gives the offset between the spheroidal readings
obtained by GPS and the Geoid defined by the model. The offsets are
given for every kilometre grid intersection point and values for points
within a square kilometre are estimated by a weighted average of the
values for each corner. As there is very little difference over a
kilometre the averaging will not give much increase in accuracy.

[As an aside a similar model (National Grid Transformation OSTN02) is
used to convert horizontal co-ordinates to OSGB36 and that model now
defines OSGB36]

Now as this model actually defines the height of mean sea level at each
location (OSGM02 has an accuracy of 2 cm for mainland Britain) the only
error in using converted GPS readings in the error in the initial GPS
reading itself.

As mentioned earlier they were recording GPS observations at the summit
for an hour. This data would then be processed against that recorded at
a base station in a known location nearby. The OS maintain a network of
active stations where the recorded data can be downloaded for free but
unless an active station was close to the point in question they would
probably have set up their own base station nearby for greater accuracy
(some of the errors effectively depend upon the location of the
receivers so to reduce them the base and rover need to be relatively
close to each other - kilometres rather than tens of kilometres for high
accuracy).

By processing the data against that recorded at a known location the
errors in the recorded data can be reduced considerably. Downloading
precise orbital data to use in the post processing can further increase
accuracy. The satellites broadcast their orbital data in real time but
there are small errors. The satellites are tracked by an array of ground
stations allowing more accurate orbital data to be calculated with a
slight delay.

The right kit and sufficiently long observation times with an
unobstructed view of the sky gathers data of high enough quality that
can then be post processed to give the accuracy quoted above ~3cm.

Impressive stuff but does 3000' above the latest and greatest Geoid
model really qualify a hill promotion?

--

Dominic Sexton

Roger said:

The message <[email hidden]>
from "Duncan Gray" <[email hidden]> contains these words:

Quoted message said:

CMCR Ltd. of Larbert and The Munro Society will be holding a joint Press
Conference to announce the true height of Foinaven. The new height has been
ratified by the Ordnance Survey.

Quoted message said:

This will take place on Friday 8th June 2007 at 10.30am in the Falkirk Golf
Club.

Any campsites up that way or will I have to camp by the side of the road
and incur the anger of Bloody Angus?

Stick your tent up omn the 18th green and see how they like it!
--
Phil Cook, last hill: Angletarn Pikes via Beda Fell.

"Dominic Sexton" <[email hidden]> wrote

Quoted message said:

I was tempted to join in earlier but needed to engage my brain first.

<snip excellent explanation>

Quoted message said:

Impressive stuff but does 3000' above the latest and greatest Geoid model
really qualify a hill promotion?

Especially when it's one foot underwater :-)

Thanks Dominic. If it turns out to be 2999.5ft surely someone can go up with
a 6ins rock and some cement?

I must admit I want to know now....

Graham

Phil Cook said:

Media Announcement

Following the successful measurement of Foinaven on 12th May 2007,
there will be a media announcement of the result on Friday 8th June
2007 at 10:30hrs which will take place at the Falkirk Golf Club,
Carmuirs, 136 Stirling Road, Camelon, Falkirk, FK2 7YP. Please refer
to www.falkirkgolfclub.co.uk for a location map.

Following the media announcement the result will appear on our
website.

Beinn Dearg will be measured on 25th August 2007.

Seems a little strange that they're re-surveying two non-Munros that
may or may not be slightly higher than thought. But not re-surveying
any of the lowest Munros, which could just as easily be a foot or two
shorter than the magic number...

--
Stop ID cards and the Database State
http://www.no2id.net/

"Duncan Gray" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

The announcement below is for:

The minority who are on the edge of their seats waiting to hear
The majority who may be mildly interested
The even bigger majority who couldn't care less

CMCR Ltd. of Larbert and The Munro Society will be holding a joint Press
Conference to announce the true height of Foinaven. The new height has
been
ratified by the Ordnance Survey.

This will take place on Friday 8th June 2007 at 10.30am in the Falkirk
Golf Club.

I await with baited breath! Seems to me a good publicity stunt? Who is
making money?
--
Craven and Pendle Birds:
Bird watching in and around Craven & Pendle.
North Yorkshire and East Lancashire.
http://craven-and-pendle-birding.org/

"Chris Townsend" <[email hidden]> wrote in message
news:[email hidden]...
<snip>

Quoted message said:

They claim their measurements are accurate to 30mm.

Nice one! On what day then? Summer? Winter? Not bad for a load of hype. It's
hilarious:-( Although someone makes a living out of all this C....

--
Craven and Pendle Birds:
Bird watching in and around Craven & Pendle.
North Yorkshire and East Lancashire.
http://craven-and-pendle-birding.org/

Simon Caldwell said:

Phil Cook said:

Media Announcement

Following the successful measurement of Foinaven on 12th May 2007

Quoted message said:

Quoted message said:

Beinn Dearg will be measured on 25th August 2007.

Seems a little strange that they're re-surveying two non-Munros that
may or may not be slightly higher than thought. But not re-surveying
any of the lowest Munros, which could just as easily be a foot or two
shorter than the magic number...

I was thinking that the other night/day when I was prattling on about
leveling when they were doing it GPS style. "How come they aren't
doing Beinn Teallach?" Also earlier in this saga I asked why not do
the twin Corbetts and The Ben Lawers two (An Stuc and the other one).
--
Phil Cook, last hill: Angletarn Pikes via Beda Fell.

In message <[email hidden]>, C R Fishwick
<[email hidden]> writes

Quoted message said:

"Duncan Gray" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

The announcement below is for:

The minority who are on the edge of their seats waiting to hear
The majority who may be mildly interested
The even bigger majority who couldn't care less

CMCR Ltd. of Larbert and The Munro Society will be holding a joint Press
Conference to announce the true height of Foinaven. The new height has
been
ratified by the Ordnance Survey.

This will take place on Friday 8th June 2007 at 10.30am in the Falkirk
Golf Club.

I await with baited breath! Seems to me a good publicity stunt? Who is
making money?

SMC when they have to issue a new version of the Munro Tables and the
Hillwalker's Guide.

Mind you - means that I will be like Roger and be able to see my name
printed in a book and not just in website and Journal.

--
Martin Richardson
663/1554 Marilyns - aiming for 777 71/118 New Donalds - only 40% to go
88/211 Irish Hewitts - 123, it's easy 42/220 Corbetts - only 81% to go