Thanks for responding. I'm comparing VMAP Level 0 to ONC CADRG data. I've
attached a screenshot of a portion of the Texas/Oklahoma border that shows
the descrepancy (notice my Az/Rng marker). I believe that this difference
could be due to our paper maps being at JNC (1:2M) instead of ONC resolution
(1:1M). I'm trying to get some ONC data right now so that I can compare.
-----Original Message-----
From: Don Dietrick [mailto:dietrick_at_bbn.com]
Sent: Saturday, December 17, 2005 8:12 PM
To: Klawetter, DG Darol (6274) _at_ IS
Cc: openmap-users_at_bbn.com
Subject: Re: [OpenMap Users] RPF and VMAP Descrepancy
Hi Darol,
What level of VMAP and RPF are you comparing against each other? I
think Level 0 VMAP was made from ONC CADRG data (1:1000000), so if
you compare it to JGA or TLM data, I'd expect the RPF to be correct,
and the VMAP data to be exceeding the precision of the source data.
I've not seen an error that large, though.
If you are looking at the VMAP browse level coverage, I think that
data is in a different datum, so you will see it off by a bit. It's
better to use the cntry02 data that's in the latest version of OpenMap.
- Don
On Dec 16, 2005, at 5:55 PM, Klawetter, DG Darol (6274) _at_ IS wrote:
> I've noticed that when displaying RPF and VMap data, the political
> borders
> as shown by the VMap political boundary layer do not match the
> borders as
> shown by the RPF paper maps. Sometimes the difference is as great
> as 1 arc
> minute. Why am I seeing this difference? The users of my map don't
> know
> which boundaries are correct.
>
> Thanks,
>
> Darol
>
> --
> [To unsubscribe to this list send an email to "majdart_at_bbn.com"
> with the following text in the BODY of the message "unsubscribe
> openmap-users"]
--
[To unsubscribe to this list send an email to "majdart_at_bbn.com"
with the following text in the BODY of the message "unsubscribe openmap-users"]
Received on Mon Dec 19 2005 - 10:35:07 EST