20050315: NEXRAD data transformation (cont.)

>From: address@hidden
>Organization: GMU
>Keywords: 200503110302.j2B32Tv2006037 McIDAS FNEXRAD composite

Hi Ying,

>Thanks Tom! It is working, just too black to notice: the stain I thought is
>actually the data, ;P
>
>Is it difficult to set the color scale?

In McIDAS, no.  I would suggest using different enhancement tables
when looking at the different NEXRAD Level III or FNEXRAD composite
products.

Try these examples displays of FNEXRAD composites in a McIDAS session:

FNEXRAD 1km N0R National composite:
ERASE;IMGDISP NEXRCOMP/1KN0R-NAT MAG=-5 -5 EU=BREF24; MAP H

FNEXRAD 2km N1P National composite:
ERASE;IMGDISP NEXRCOMP/2KN1P-NAT MAG=-3 -3 EU=PRE1; MAP H

FNEXRAD 4km NTP National composite:
ERASE;IMGDISP NEXRCOMP/4KNTP-NAT MAG=-2 -2 EU=PRET; MAP H

Remember that the colorization of a display does not change data values
in the image.  Image data values are values that range from 0 to 255 in
1-byte images, 0 to 1024 in 2-byte images, etc.

So, when you convert an image into GeoTIFF format, the data values will
be the same as they were in the original image: values that range from
zero (black) to 255 (white).  Since I am not familiar with GIS systems
(presumably what you are using to look at the GeoTIFF output), I can
not advise you on how to color (enhance) those displays.

Cheers,

Tom
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