State GeoTIFF and Lidar Data
This is a bit outside my normal area of work, but there is this article:
@jimcox There is a web page that contains the parcel metadata at https://maps.vcgi.vermont.gov/gisdata/metadata/CadastralParcels_VTPARCELS.htm and it says its SPCS Vermont zone. There is also a page where the data can be downloaded in several formats:
https://geodata.vermont.gov/datasets/VCGI::vt-data-statewide-standardized-parcel-data-parcel-polygons-1/about
I'm not sure how to examine the downloaded data to see what format it purports to be in. I suppose I could find a point in the raw data and see if the values look anything like SPCS. Another approach would be to find an NGS monument that lies on a parcel boundary, but I can't think of any.
Apart from the problems created by the projection, there is the obvious problem of trying to piece together surveys performed over the past 250 years into a parcel fabric.
I was looking at the webservices section of this page
https://geodata.vermont.gov/pages/parcels
It suggests that such data is in web mercator
If I go the endpoint for the WFS service listed, I get the capabilities of the server. It indeed confirms that both active and inactive parcels are in those terms
Of course, it is possible for Downloads to be in a different coordinate system
Extract from the server capabilities:
<wfs:FeatureTypeList>
<wfs:FeatureType>
<wfs:Name>FS_VCGI_VTPARCELS_WM_NOCACHE_v2:Cadastral_VTPARCELS_poly_inactive</wfs:Name>
<wfs:Title>Cadastral_VTPARCELS_poly_inactive</wfs:Title>
<wfs:DefaultCRS>urn:ogc:def:crs:EPSG::3857</wfs:DefaultCRS>
<ows:WGS84BoundingBox>
<ows:LowerCorner>-73.42128978 42.72995280</ows:LowerCorner>
<ows:UpperCorner>-71.54007965 45.00977947</ows:UpperCorner>
</ows:WGS84BoundingBox>
</wfs:FeatureType>
<wfs:FeatureType>
<wfs:Name>FS_VCGI_VTPARCELS_WM_NOCACHE_v2:Cadastral_VTPARCELS_poly</wfs:Name>
<wfs:Title>Cadastral_VTPARCELS_poly</wfs:Title>
<wfs:DefaultCRS>urn:ogc:def:crs:EPSG::3857</wfs:DefaultCRS>
<ows:WGS84BoundingBox>
<ows:LowerCorner>-71.80190954 44.78555562</ows:LowerCorner>
<ows:UpperCorner>-71.80123951 44.78590786</ows:UpperCorner>
</ows:WGS84BoundingBox>
</wfs:FeatureType>
</wfs:FeatureTypeList>
While I have not used them in years, New Jersey has aerial photos in State Plane, they were called Mr. Sidds, not sure they still are. They were free to download and I used them in the same fashion as you, overlaying deed plots on the aerials, based on physical features. It was great for creating search points.
We also have free, downloadable LIDAR for the whole state but we don't use it for anything other than presentation purposes.
I use NC's free orthoimagery daily and the lidar derived surface as supplements and additional checks against blunders for aerial lidar missions. I think North Carolina is on its sixth statewide lidar survey. The benefits to the public are enormous.
The VT Ortho Finder at https://maps.vcgi.vermont.gov/OrthoFinder/ to download orthos does not work for me when I try it. Does it work for you?
I just helped a buddy get topo for his property in the boonies of CO. I was surprised at how much very detailed LiDar coverage they offer. Not having goofed with it too much I downloaded a large DEM (.img file), brought it into QGIS in CO SPC (data was UTM 13N), created a polygon and clipped it to the smaller 5 ac area, created contours and exported to dxf. Then brought into C3D and created a surface that was remarkably fit to the underlying aerial geomap.
works for me. Zoom to a tile, and a popup appears to download image and world files. The download is 2 steps (Tiff or JP2) and (TIFW or JP2). This is a slick Feature service. Excellent metadata too.
I'm sorry this is such a late response. I haven't visited this site in ages due to not-enough-spoons! (you have so many spoons per day and sometimes you run out--mine keep running out due to aged family members)
It'll be due to what, if any, transformations are done between NAD83 (2011) and WGS84. At least in Esri, the internal workflow is unproject from the projected coordinate system to its GCS, apply a geographic/datum transformation if needed/set to the target PCS's GCS, project to PCS. The two projections are very precise so no issues there. That's for vectors. Rasters and similar data types are doing more direct conversions but using the same workflow to generate the source/target coordinates.
