[OpenLayers-Users] Reprojection question

[Christopher Schmidt]

On Tue, Dec 05, 2006 at 05:20:09PM -0800, Donal wrote:
> I don't understand why my mapfile set up doesn't prevent the shift between
> the 2 raster layers; does the mapfile snippet below not project all layers
> into the 4326 projection?

It sounds like the question here is really, "Why do my two ka-map layers
shift when I switch between them"? The answer to that might be "You have
chosen an incorrect EPSG code for your AirPhoto data". The mapfile you
have pasted here should result in the data lining up. If it doesn't,
then nothing OpenLayers can do could guess correctly where the data
should be.

You might check that your AirPhoto data is actually in EPSG:31066. If it
does turn out to be, you might check whether your 'rasters' data is in
EPSG:4326 -- if the shift is about 100M, you might be having a datum
shift error.

I think the answer is to figure out the source of the shift in your
tiles. Once you do that, you'll probably have better luck.

Regards,
-- 
Christopher Schmidt
MetaCarta