Bsb Charts Canadian Free



##Comments to a header that is close to what will actually be used.

  1. Name of chart from the chart. Warning: do not use commas ','.
  2. Chart number. Plan A on 23456 should be named 23456_A
  3. Size of picture Pixel x coordinate
  4. Size of picture Pixel y coordinate
  5. Scale of the chart from the chart.
  6. Geodetic datum, for example WGS84, from the chart. I not defined on the chart write 'UNKNOWN' No guesswork,it is either stated, or said to be a local datum that cannot be related to WGS84. Charts released earlier than 1990 (?) and conforming toWorld Geodetic System should be WGS72, unless stated otherwise. The difference between WGS 84 and WGS 72 is minor.
  7. Projection, almost always MERCATOR, a few charts are TRANSVERSE MERCATOR. We should not bother with other projections,GNOMONIC small scale great circle charts etc. If we come across large scale plans with GNOMONIC projection this should be used, say1:50,000 or larger. High latitude 'Lambert Conformal Conic Projection' should be skipped, for now. OpenCPN only handles Mercator andTransversal Mercator. I don't think that we will see any Polyconic charts.
  8. For Mercator charts this is the latitude where the scale is valid. If available on the chart, use that value.If it is not available on the chart use the average value of the latitude of the upper and lower edge, to the nearest 1/10 of a degree.For Transverse Mercator charts use the average longitude of the eastern and western edge.Treat a possible large scale gnomonic as a Mercator chart.
  9. SK is the skew angle of charts that are not 'North Up'. For North Up the value is 0.0
  10. TA is he text angle, more or less always 90.0
  11. Unit for soundings from the chart, mostly METERS
  12. Datum for soundings from the chart, for ex MLWS, LAT
  13. x and y resolution, meters per pixel. Not necessary for us to compute. OpenCPN handles this.
  14. Chart edition date copied from the chart,inf in SW corner, except, there must be no commas.
  15. Our release edition.
  16. Our release date.
  17. Georeferencing, standard case - simple 4 corner chart, use the 4 corners, starting in the SW corner proceeding clockwise.Format: x pix,y pix, lat, long. Lat & long i decimal degrees, to 8 decimals, where N lat and E long are positive.One reason to use all 4 corners is to catch skewed and warped charts, and calculate SK (8a)
  18. Standard case, just copy the lat & long from the REFs.
  19. Corrections in seconds of arc to bring the chart to WGS84. This is generally given on the chart(if they exist),in a format where the corrections are in minutes of arc for plotting a WGS84 position on the chart.This correction must be transformed to seconds of arc and the signs reversed(we are doing the reverse to the case stated on the charts). These values are sometimes difficult to find on the chart.
  20. If a chart spans the 180th meridian = > CPH/180.0, else => CPH/0.0. So CPH/ is 0.0 for most charts. Note thatOpenCPN handles transiting the 180:th meridian while a few other plotters don't.

Raster charts are exact scanned copies in BSB format of paper charts available as discounted bundles or as individual digital raster charts for CAD$ 25.00 each. Browse other products: Canadian topographic maps, printed on paper or plastic.

  1. Canadian Hydrographic Services (CHS) is responsible for production, marketing, sales and distribution of its digital chart data and digital tide data, as well as licensing dealers. CHS offers Raster Navigational Charts in the BSB v4 format on CD.
  2. Free raster charts from NOAA-All US charts on a DVD. NV.charts USA- NV.charts Europe. BSB 4.0 from Maptech- Canadian BSB 4.0. If you have Maptech US Digital Chartkit, TIKI will also read Aero charts and NavPhos.
Bsb

Noaa Bsb Charts Download

IFM is not used as tif2bsb and imgkap calculates this value and ads it to the header on the final kap,together with other values such as RGB.

Charts

###This is one of the simpler bsb/kap file combinations, one kap and one bsb file. Maybe not the greatest example since it uses NAD27 instead of WGS84.

Some programs are a bit picky about the content of the bsb and kap files.

Try to document the different tags.

Bsb Charts Canadian Freestyle

Content of 3001.bsb:

Canadian

Content of 300101.kap, just the start of the header:

more REFs, PLYs....

Bsb charts

Bsb Charts Canadian Free Shipping

Bsb

The libbsb project explains some of the tokens.http://libbsb.sourceforge.net/bsb_file_format.html
For simplicity, here is a local copy of above:

Bsb Charts Canadian Freedom

Clone this wiki locally