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[IDV #HJT-379438]: Displaying Level III McIDAS Area Files

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  • Subject: [IDV #HJT-379438]: Displaying Level III McIDAS Area Files
  • Date: Thu, 21 Sep 2006 09:38:02 -0600
Hi Greg-

Jeff's answer is correct.  The basic problem is that when reading
from disk, we have no way of calibrating the image. The ADDE server
does the calibration when we read from the remote systems (and we
calibrate when reading the raw Level III data).  The only 
solutions would be to:

- put the files on a local ADDE server and let the server calibrate

or 

- when you grab the images through McIDAS IMGCOPY, use the UNIT= keyword
to get a pre-calibrated image.  The UNIT's for Level III are:

ECHO - Reflectivity
VIP  - Vip level
TOPS - Echo Tops
RAIN - Precip
H2O  - VIL
VEL  - Radial Velocity

Here's the imgcopy command I used:

IMGCOPY RTNEXRAD/N0R MYDATA/IMAGES.2001 UNIT=ECHO ID=FTG

When you display it in the IDV, you'll need to still set the range
if you use the image display.

Don Murray

> >
> > I would like to display a Level III McIDAS Area file in IDV. It loads OK 
> > but the display is black.  Any thoughts?
> >
> 
> There is actually data there but the range of the data is ~0-6
> and that is only in a small part of the image. The rest is 0.
> With the default color table range of 0-255 you are getting mostly
> black (using the gray scale color table).
> 
> Try changing the Color range - right click on the color bar
> and select "Change Range"
> 
> You can also add a data probe or a data transect on this image to
> see the actual values.
> 
> 
> Don is out for a few days but I'll ask him to look at this file
> to see if there is anything wrong about the data or our reading
> of the data.
> 
> -Jeff
> 


Ticket Details
===================
Ticket ID: HJT-379438
Department: Support IDV
Priority: Normal
Status: Open