SeeYou incorrect waypoint altitudes

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.

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 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

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).

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 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

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!

I have create and fixed several turnpoint lists. It is is amazing to see when some people quickly add turnpoints they leave the altitude at O MSL!!!
I scan for this first thing when I redo a list. That could really cause someone to hit the dirt thousands of feet earlier than they thought going to a point.
Chris