Thanks Jessica,
both raster and vector are Lat/Long NAD 27 ContUS. Raster (topo quad) again
was exported originally in this one and only projection - vector was
translated from DLG and reprojected in the above mentioned projection to fit
the purposes of my project.

After all your answers I still do not know how to fix this problem (I knew
that having data in different projections would cause shift, but I never
expected it to happen after I reprojected everything beforehand).
Please helpppppp!!!!
Thanks again all!

Gabriela Cardenas
- GIS Technician -


-----Original Message-----
From: Jessica [mailto:[EMAIL PROTECTED]
Sent: Friday, July 18, 2003 11:54 AM
To: Gabriela Cardenas
Subject: Re: MI-L Raster vs. vector: shift


On 7/18/03 11:15 AM, "Gabriela Cardenas" <[EMAIL PROTECTED]> wrote:

> Josh and David,
> thanks for your answer! As I mentioned, the vector and the raster ARE same
> projection, I reloaded the raster topo special for this project! Raster IS
> registered correctly, as this is done through SureMaps, topo quad on top
of
> quad.
> The other thing is that only ONE vector layer shifts, of all other base
> vector tables opened; I wonder if it's a problem from data creation.
> This really is a big fence in running this project...
>
> Gabriela Cardenas
> - GIS Technician -
>
>
> -----Original Message-----
> From: David Reid [mailto:[EMAIL PROTECTED]
> Sent: Friday, July 18, 2003 9:59 AM
> To: 'Gabriela Cardenas'
> Subject: RE: MI-L Raster vs. vector: shift
>
>
> I'm no expert but have worked with a lot of rasters and digitizing. I have
> seen three separate issues with vectors seeming to 'shift'.
>
> 1. Sometimes commons and easy to over look if your vector and raster
tables
> are in similar projections. Case in point raster in Lat/Long Nad 83 but
> vector file in Lat/Long NAD 27. Projections are very similar and easy to
> overlook however, visual shift is detectable especially with the Mapinfo
> 'Snap'.
>
> 2. Also a common trait and I think a slight bug in Mapinfo.  Zoom level
and
> raster pixel width. I've never been able to nail this one down but when
> digitizing a very long line, once finished and the screen is refreshed,
the
> latter half portion of the line just digitized is off by several pixels.
It
> would appear that adjusting zoom to a whole number reduces this effect.
(ie
> 0.4miles instead of 0.4123, 1.0 miles rather than 0.9876 *replace miles
with
> your desired unit)
>
> 3. Your raster just isn't registered quite accurately enough.
>
> All in all, the only permenant effect is that as noted in #2 above.
> Permenant in that the line is off and requires correction. Otherwise,
> especially in #3, once the raster is removed and the vector table either
> refreshed to another known good raster, or either closed, then reopened,
the
> vector allignment will return to it's correct origin.
>
>
> Hope this helps some.
>
> David
>
>
>
> -----Original Message-----
> From: Gabriela Cardenas [mailto:[EMAIL PROTECTED]
> Sent: Friday, July 18, 2003 10:39 AM
> To: [EMAIL PROTECTED]
> Subject: MI-L Raster vs. vector: shift
>
>
> Hello dear MI listers,
> did anyone come across this probl in MapInfo Proff. 6.5?
> I have a multitude of vector files and few rasters, all in same
projection.
> when I work with vector ONLY, I measure a certain distance between objects
> from different layers. The moment I open the raster, one of the vector
files
> (the one I care about the most, the one that I am updating and trying to
> keep errors to a min), SHIFTS. any ideas appreciated!
>
> Gabriela Cardenas
> - GIS Technician -
>
>
>
>
I ran into a similar problem where vector lines overlayed on DOQQs appeared
shifted. My MapInfo guru informed me that the I shouldn't be using a
coverage that was created or re-projected into just Long/Lat. Problems tend
to emerge when raster data is brought into the workspace. I was aslo told
that I should have DRGEs (USGS topo) and DOQQs in the same map window.
Perhaps this will work.

Jessica Mitchell
Spatial Analyst
Biota Research and Consulting, Inc.
Jackson, WY 83002




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