SeeYou incorrect waypoint altitudes

On Saturday, February 1, 2020 at 11:48:39 AM UTC-8, Darryl Ramm wrote:
On Friday, January 31, 2020 at 7:59:13 PM UTC-8, soaringjac wrote:
Just started using seeyou for the first time. I created some waypoints in seeyou and noticed the altitude shown for some of the waypoints are way off. I double checked the exact same point in Google earth and the difference is about 1000'. This isn't the case for all custom waypoints I made, but it is true for most of them. How are you guys creating accurate waypoints and waypoint altitudes. Kind of crazy that seeyou is so off!

Describing exactly wha you are doing and providing sample data will help you get useful help.

Are you using SeeYou Windows app, SeeYou Mobile or SeeYou cloud?

How exactly are you creating a waypoint and how exactly are you looking at its elevation? If say you are looking at stuff in SeeYou Mobile then it may be you are getting confused with waypoint elevation, arrival height, etc..

Assuming you are using SeeYou Windows app as you move the cursor around you should see the elevation shown in the lower window border next to the cursor latitude and longitude, that changing display gives you an idea of the elevation data resolution. Elevation data is only useful within that resolution, if you are trying to pick super fine resolution elevation features it's not going to work. And pragmatically for anything important people usually hand-edit waypoint files, including elevation if needed.

If your SeeYou is not or has not been connected online I imagine it's possible that SeeYou has not downloaded the elevation data (I assume it's still downloading NASA elevation data, even that is a bit more hidden than it used to be).

I am using SeeYou windows app to create waypoints. I scroll and zoom around the map to find the place i want to mark, then i right click and select "waypoint here". Right clicking brings up a window with the elevation data in it. I do see the elevation data shown in the bottom left as well like you mention

On Saturday, February 1, 2020 at 9:43:59 AM UTC-8, Martin Gregorie wrote:
On Sat, 01 Feb 2020 07:38:03 -0800, soaringjac wrote:

On Saturday, February 1, 2020 at 7:14:46 AM UTC-8, Paul Remde wrote:
Hi,

I suspect that one of 2 things is happening.
- You may be using a bad turnpoint database. I recommend the data
found he
http://cumulus-soaring.com/seeyou.htm#Downloads
- If you are viewing a flight log, SeeYou can automatically use the
take-off and landing elevations and the SeeYou ground elevation
database to offset all the flight log points to account for barometric
pressure changes. It is a very nice feature.

You may want to check-out my SeeYou Tips document.
http://cumulus-soaring.com/seeyou/SeeYou-Tips.pdf

Best Regards,

Paul Remde

On Friday, January 31, 2020 at 9:59:13 PM UTC-6, soaringjac wrote:
Just started using seeyou for the first time. I created some
waypoints in seeyou and noticed the altitude shown for some of the
waypoints are way off. I double checked the exact same point in
Google earth and the difference is about 1000'. This isn't the case
for all custom waypoints I made, but it is true for most of them. How
are you guys creating accurate waypoints and waypoint altitudes. Kind
of crazy that seeyou is so off!

Thanks Paul! I am not using any turnpoint database and not viewing any
flight log. I am just trying to mark some local landmarks as waypoints
to put into my S100 vario. Im going to play around with it a bit more
and see if i can figure out whats going on, but to me it seems like the
see your elevations are not accurate. I guess i can always create the
waypoints and then edit their altitudes based on the alt i get from
google earth, which kind of sucks

Post one of the problematic turnpoints here so we can see what might be
wrong. CUP files are just plaintext, so almost any program that can
display a text file can display it for cut'n pasting - even Word.


--
Martin | martin at
Gregorie | gregorie dot org

All you need to do to replicate is to make a waypoint in seeyou and note the elevation, then go to google earth or something similar and get the elevation for the same location. Most likely it is pretty different. In a couple cases for me its almost 1000' difference

On Sunday, February 2, 2020 at 7:41:03 AM UTC-8, Tango Eight wrote:
On Friday, January 31, 2020 at 10:59:13 PM UTC-5, soaringjac wrote:
Just started using seeyou for the first time. I created some waypoints in seeyou and noticed the altitude shown for some of the waypoints are way off. I double checked the exact same point in Google earth and the difference is about 1000'. This isn't the case for all custom waypoints I made, but it is true for most of them. How are you guys creating accurate waypoints and waypoint altitudes. Kind of crazy that seeyou is so off!



I use https://viewer.nationalmap.gov/basic/ for accurate elevation data.

I used SeeYou 4 for a number of years and it worked pretty well in this regard. More recent versions... not so much. Ridge top waypoints created in SeeYou always have elevations lower than actual. I have seen errors as large as 600'.

Evan Ludeman / T8

Thanks for the link T8!

soaringjac wrote on 2/2/2020 8:33 AM:
On Saturday, February 1, 2020 at 7:48:36 AM UTC-8, Eric Greenwell wrote:
soaringjac wrote on 1/31/2020 7:59 PM:
Just started using seeyou for the first time. I created some waypoints in seeyou and noticed the altitude shown for some of the waypoints are way off. I double checked the exact same point in Google earth and the difference is about 1000'. This isn't the case for all custom waypoints I made, but it is true for most of them. How are you guys creating accurate waypoints and waypoint altitudes. Kind of crazy that seeyou is so off!

For what purpose will you use the waypoints? If it's for task planning, the
correct elevation doesn't matter; if it's for potential landing places, you should
not depend on SeeYou, but on a more accurate source. SeeYou is a flight planning
tool, and it's your flight computer that needs elevation accuracy. I use official
databases as my first choice; for landing places not in the official databases, I
use databases from pilots I trust, sometimes from Google, perhaps topographic
maps. I also plan to arrive higher at those landing places, partly because the
elevation may not be known as accurately as airports on the charts.


Just adding a couple local landmarks to my S100, mainly going to use to see if I have glide to the various waypoints. Not doing any XC or competition stuff. I might try some databases but it seems a bit overkill for now. I just want a couple local landmarks.

I maybe be assuming the wrong things. What are you using as your flight computer,
and does it already have the local airports in it?

Usually, we use "landmark" for point of reference only, like a mountain peak or
bridge. By "landmarks", do you mean "places I could land safely?

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1

Post the actual waypoint data here... it’s just ASCII text. Then we have a chance of seeing what is going on.

This is *not* what happens for typical users. If it did everybody would be screaming. So no us just going and trying is not going to help you because it works fine except as noted near fine resolution peaks etc. So again, just post the waypoints you are seeing errors for.

On Sunday, February 2, 2020 at 4:12:02 PM UTC-5, Darryl Ramm wrote:
Post the actual waypoint data here... it’s just ASCII text. Then we have a chance of seeing what is going on.

Here you go. I created this waypoint about 3 minutes ago. Use whatever tool you like to correlate lat/long/elevation. Actual elevation closer to 1220m....

"Brumley Mountain",,,3650.274N,08206.228W,1091.5m,1,,,,,,

T8

On Sun, 02 Feb 2020 14:26:54 -0800, Tango Eight wrote:

On Sunday, February 2, 2020 at 4:12:02 PM UTC-5, Darryl Ramm wrote:
Post the actual waypoint data here... it’s just ASCII text. Then we
have a chance of seeing what is going on.

Here you go. I created this waypoint about 3 minutes ago. Use whatever
tool you like to correlate lat/long/elevation. Actual elevation closer
to 1220m....

"Brumley Mountain",,,3650.274N,08206.228W,1091.5m,1,,,,,,

Interesting, so I went looking with Google Earth...

That point seems to be on the side of a forested ridge at 1187m on the
Blue Mountains in VA.

A more obvious TP would be the rock outcrops at 35 50.11.9N 82 06.1492W,
or 3550.119N 08206.119W in Seeyou format, but of course ymmv.

Of course, this all assumes the OP didn't mean "Bromley Mountain", at the
top of the Bromley Ski Resort, Vermont at 996m (43 13'15.67"N 072
56'19.37W or 4313.157N 07256.1837W in SeeYou format) - which would be a
much more obvious turnpoint.


--
Martin | martin at
Gregorie | gregorie dot org

On Sunday, February 2, 2020 at 7:28:38 PM UTC-5, Martin Gregorie wrote:
On Sun, 02 Feb 2020 14:26:54 -0800, Tango Eight wrote:

On Sunday, February 2, 2020 at 4:12:02 PM UTC-5, Darryl Ramm wrote:
Post the actual waypoint data here... it’s just ASCII text. Then we
have a chance of seeing what is going on.

Here you go. I created this waypoint about 3 minutes ago. Use whatever
tool you like to correlate lat/long/elevation. Actual elevation closer
to 1220m....

"Brumley Mountain",,,3650.274N,08206.228W,1091.5m,1,,,,,,

Interesting, so I went looking with Google Earth...

That point seems to be on the side of a forested ridge at 1187m on the
Blue Mountains in VA.

A more obvious TP would be the rock outcrops at 35 50.11.9N 82 06.1492W,
or 3550.119N 08206.119W in Seeyou format, but of course ymmv.

Of course, this all assumes the OP didn't mean "Bromley Mountain", at the
top of the Bromley Ski Resort, Vermont at 996m (43 13'15.67"N 072
56'19.37W or 4313.157N 07256.1837W in SeeYou format) - which would be a
much more obvious turnpoint.


--
Martin | martin at
Gregorie | gregorie dot org

It's a ridge route. If you've done any flying of that sort, it'll make sense. If you haven't... look at the the topo and do the thought experiment.

https://viewer.nationalmap.gov/basic...vail=&refpoly=

T8

On Sunday, February 2, 2020 at 1:12:02 PM UTC-8, Darryl Ramm wrote:
Post the actual waypoint data here... it’s just ASCII text. Then we have a chance of seeing what is going on.

Here is the waypoint
"Baden-Powell",Badenell,,3421.517N,11745.883W,2631.6m,1,, ,,,,,

actual altitude is about 2865 meters

There is nothing specific about this waypoint, so it really does not matter.. Just click around the map in SeeYou and add some random waypoints and then compare to google earth altitudes