Calibrate map with Lambert projection

  • Hello, I got map from US army which use "Lambert conformal conic projection". How can i calibrate these maps xith Qv7 ? Thank you for your help.

  • Could you please provide the map legend of this map? In addition to the projection name you also need the projection parameters and the geodetic datum of the map, usually they are indicated in the map legend.


    If you got the map from an online resource please provide the link to it.

    Grüße
    Hans


    "The universal aptitude for inaptitude makes any human accomplishment an incredible miracle." (John Paul Stapp)

  • Salu Didier!


    These maps can be calibrated pretty straight forward, except for the datum which is not always clear. The map legend says 49°20' and 54°40' for the standard parallels, as the longitude of origin I chose the vertical center meridian of the map. I did a sample calibration with these parameters and chose WGS84 as the datum:


    2018-11-20_18-54-27.jpg


    The resulting QV calx file: txu-pclmaps-oclc-22834566_e-4c_jpg_calx.zip


    If it does not fit properly enough, you may have to try another datum, as Kasakstan was part of the former Soviet Union I would try Pulkovo first.

    Grüße
    Hans


    "The universal aptitude for inaptitude makes any human accomplishment an incredible miracle." (John Paul Stapp)

  • Bonjour, Following your proposal, i tried many options as using Pulkovo but the changes were very small. It appear that after the calibration 3 geocalibration were good but the Bottom left corner was wrong. For exemple with the map E-7D, instead of N48° - E 88° which was the Bottom left corner, i got N 48°0'55'' and E 88°7'38'' with QV. So, i change the calibration of this corner as follows; 88° less 7'38" ie 87°52'22". And by this way, the calibration is quite good enough all around the map.

    After trying many options, i think that this one is the best even if not the better.

    Thanks for your help. Didier