ChartTiff Geo's are generated with latest USGS DRGs available
  Totally Collarless  and Seamless Topographic Maps

• No Setting Clipping or Setting a Transparency Layer required
  Plug compatible with your GIS System

• Complete Coverage of the US including Alaska and Hawaii

• Includes all 1:24,000, 1:100,000 and 1:250,000 scale files

• 250 DPI resolution, 256 color palette

• Standard GeoTiff format enhanced with ChartTiff Extensions
  Plus ESRI "tfw" and MapInfo "tab" files.

• Optional JPEG format.  Selectable at Check-Out.

• Add Shaded Relief to Geo Topographic Maps
   Click here for details

   Collared DRG's standard USGS collared Topographic Maps

• Complete Coverage of the US including Alaska and Hawaii

• Includes all 1:24,000, 1:100,000 and 1:250,000 scale files

• 250 DPI resolution, 256 color palette

• Standard GeoTiff format enhanced plus ESRI "tfw" and MapInfo "tab" files.

• Optional JPEG format.  Selectable at Check-Out.

• Add ChartTiff Enhanced DRG Collars
   Click here for details

• Add Shaded Relief to DRG Topographic Maps.
   Click here for details

• Any projection available 
       - UTM- User Selectable Zones and datum
      - State Plane - User Selectable Zones and datum
       - Latitude / Longitude - User Selectable datum                                       
       - Request a quote for other projections.  See REQUEST
  
  Scales Available
        - 1:24,000 Scale ChartTiff Geo's (Collarless / Seamless DRGs)
        - 1:100,000 Scale ChartTiff Geo's (Collarless / Seamless DRGs)
        - 1:250,000 Scale ChartTiff Geo's (Collarless / Seamless DRGs)
        - 1:24,000 Scale ChartTiff DRG's (Collared DRGs)
        - 1:100,000 Scale ChartTiff DRG's (Collared DRGs)
        - 1:250,000 Scale ChartTiff DRG's (Collared DRGs)

Topographic Maps Sold by Full Degree                    

• Any projection available                                        $50.00 / Degree
       - UTM- User Selectable Zones and datum
      - State Plane - User Selectable Zones and datum
       - Latitude / Longitude - User Selectable datum                                       
       - Request a quote for other projections.  See REQUEST

• Includes all 1:24,000, 1:100,000 and 1:250,000 scale files.

• Includes ESRI ".tfw" and MapInfo ".tab" World files

• Includes the Full set of Original collared USGS DRG's

• Available via Download and Custom DVD 
          
• Any Collarless / Seamless Geo Quad only    $2.00
  Any Original Collared USGS DRG Quad only $1.00
  
  
• Available Projections
  UTM - User Selectable Zones - NAD27 / NAD83 / WGS72 /  WGS84
  State Plane - User Selectable Zones - NAD27 / NAD83
  Latitude / Longitude - NAD27 / NAD83 / WGS72 /  WGS84

• Available via Download and Custom DVD 
  
• Any Collarless / Seamless Geo Quad
  Areas available from 3.75 Minutes to 5 Degrees Width / Height, 
           based on scale:
  
  
• Available Projections
  UTM - User Selectable Zones - NAD27 / NAD83 / WGS72 /  WGS84
  State Plane - User Selectable Zones - NAD27 / NAD83
  Latitude / Longitude - NAD27 / NAD83 / WGS72 /  WGS84

• Available via Download and Custom DVD 
  
• Custom Area Topographic Maps with collars and legends ready for plotting 
  Areas available from 3.75 Minutes to 6 Degrees Width / Height, 
           based on scale:
  
  
• Available Projections
  UTM - User Selectable Zones - NAD27 / NAD83 / WGS72 /  WGS84
  State Plane - User Selectable Zones - NAD27 / NAD83
  Latitude / Longitude - NAD27 / NAD83 / WGS72 /  WGS84

•  A ChartTiff Geo map is created from the original USGS DRG topographic maps.  The quad is first projected to your requested projection,  then cropped to the map extents.  The voided areas of the map are then filled with the necessary adjacent map information to make the map and Tiff file rectangular.

• ChartTiff Geo raster images are geometrically registered at the pixel level from map to map; even from degree to degree.   ChartTiff Geo raster images allow for easy panning from one map to another, without worrying about map overlap and transparency problems associated with other map products.

• The Tiff files are then enhanced to the ChartTiff format with additional tags. ChartTiff is a superset of the GeoTiff standard.
  • Click here to download ChartTiff standard in a PDF format.
  • Click here to view tag extensions used in ChartTiffs.
  • Click here to download GeoTiff standard in a PDF format.
  • Click here to download Tiff 6.0 standard in a PDF format.

Normal USGS DRG with collars

ChartTiff Geo without collars

QUAD Naming Convention

Quad name format was developed by the USGS and is used to specify the geographic location of a quad map in latitude / longitude coordinates. For example, for quad name O34119d6, the letter "O" specifies the map scale 1:24,000. The number 34 specifies base latitude of 34 degrees, and the number 119 specifies base longitude of 119 degrees.

Each 1:24,000 map location is 7.5 minutes by 7.5 minutes; which equates to 8 x 8 = 64 quad locations in a 1 degree by 1 degree square of geographical area. The 8 rows and 8 columns of quad locations within each square degree are designated by the last
2 letters of the quad name. In this example (O34119d6), the quad is the fourth row (the letter 'd'), and sixth column (the digit '6').  Rows are designated from 'a' (south-most) to 'h' (north-most), and columns are designated from '1' (east-most) to '8' (west-most). The 64 quad locations for the example are:
 

The following table lists the partial degree values for the
bottom (south) edge of each quad location:

The following table list the partial degree values for the
right (east) edge of each quad location:

For a more detailed description of quad name standards, see:

                       http://topomaps.usgs.gov/drg/drg_name.html

MAP SCALES

ChartTiff maps use the USGS file naming convention, in which the first letter of the file name determines the size and scale of the file:

The remainder of the file name includes the encoded values of latitude, longitude, and relative location of the map image.  For more information on USGS standards, see:

                      http://topomaps.usgs.gov/drg/drg_name.html

Note: Most 7.5 x 7.5 minute USGS maps are distributed as O files (1:24,000 scale), but some are only available as P, L, or K files.  Therefore, some ChartTiff DRG files are only available as P, L, or  K files. ChartTiff Geo files (collarless/seamless maps) are
automatically processed into corresponding O files.