[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[McIDAS #NGM-207442]: mcidas

This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.

  • Subject: [McIDAS #NGM-207442]: mcidas
  • Date: Mon, 13 Dec 2010 10:57:40 -0700
Hi Sepideh,

re:
> the problem is our images are just between 10 N and 25 S and 40W to 80 W
> but when i imgcopy them without defining the size and LATLON, i get very
> strange answers for lat and lon,
> like 2*10^5.

This is something that I have never run into.  Am I correct to assume that
when you specify the LATLON extents that you do not have this problem?

re:
> and the resolution of goes 7 is 1 Km,

I assume that the resolution of GOES-7 visible is nominally 1 km like the other
GOES platforms.  I further assume that the resolution of the infrared channels
is either 4 km (e.g., the 10.7 um channel) or 8 km (e.g., the water vapor 
channel).
I can't remember if these assumptions are correct, however; it has been a long
time since I looked at GOES-7 imagery.

> which is about 0.01 degree.

Correct.  1 degree of latitude is 111.1 km, so 1 km is approx 0.01 degrees.

re:
> but the resolution that we get from netcdf files are much finer than that.

I do not know how this is possible unless you have used the MAG= keyword when
doing the IMGCOPY.  A MAG= value that is >1 will cause the replication of pixels
in the output image (a MAG= value <1 will result in a sampling of the pixels
from the original image to the netCDF copy).

Question:

- what was the IMGCOPY command you used when producing an output netCDF image
  that appears to have resolution greater than 1 km?

re:
> How we can use IMGREMAP?

IMGREMAP is used to convert an image's projection and resolution.  There is
in-program HELP for IMGREMAP (HELP IMGREMAP) and a section in the McIDAS
User's Guide that explains all of the options and gives some illustrative
examples:

Unidata HomePage
http://www.unidata.ucar.edu

  Unidata McIDAS
  http://www.unidata.ucar.edu/software/mcidas

    Unidata McIDAS-X User's Guide
    http://www.unidata.ucar.edu/software/mcidas/current/users_guide/toc.html

    Chapter 3: Commands
    Commands by Alphabetical Order
    
http://www.unidata.ucar.edu/software/mcidas/current/users_guide/CommandsbyAlphabeticalOrder.html#26670

    IMGREMAP
    
http://www.unidata.ucar.edu/software/mcidas/current/users_guide/IMGREMAP.html#35510

Cheers,

Tom
--
****************************************************************************
Unidata User Support                                    UCAR Unidata Program
(303) 497-8642                                                 P.O. Box 3000
address@hidden                                   Boulder, CO 80307
----------------------------------------------------------------------------
Unidata HomePage                       http://www.unidata.ucar.edu
****************************************************************************


Ticket Details
===================
Ticket ID: NGM-207442
Department: Support McIDAS
Priority: Normal
Status: Closed