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Data Sizes

I almost forgot about giving you the sizes for the NH images. I have
included a few options for the IR., i.e. 4 separate areas, 4 bands in
one area, or all 5 bands in one area at 4 km.
For vis you have 2 byte or 1 byte and 1 km vs 2 km.  Also the coverages
for G-8 an G-10 are changing in early May but I would doubt if the
change will have much affect on the sizes. So if you use these as
ballpark figures you should be safe.

I checked with a few the of the GOES group here, and they all said if
you want more than a pretty picture you want 2 byte visible.  The real
differences are seen in low light.  If you enhance a low light 1 byte
image, the loss of 20% of data really shows.  Apparently a Don Hilgers
from CIRA recently wrote a NESDIS tech memo on the subject of 1 byte vs
2 byte if you are really interested.

AWIPS is using 1 byte for vis, IR and even sounder!  But the consensus
is this is the wrong thing to do.

Let me know if you have questions or if this is not clear.

GOES EAST        Northern Hemisphere coverage
Visible 1km          ~204 MB per 2 byte image
                           ~103 MB per 1 byte image

Visible 2km          ~51.5 MB per 2 byte image
                           ~26.2 MB per 1 byte image

IR bands 4km       ~13 MB per 2 byte band  (13 * 4 per image)
All IR bands 4km  ~51 MB for all 4 IR bands in one AREA

All bands 4km       ~64 MB for all 5 bands at 4km in one AREA (vis + 4
IR)

GOES WEST        Northern Hemisphere coverage
Visible 1km            ~146 MB per 2 byte image
                            ~ 73.5 MB per 1 byte image

Visible 2km            ~ 37 MB per 2 byte image
                            ~ 19 MB per 1 byte image

IR bands 4km        ~ 9.4 MB per 2 byte band (9.4 *4 per image)
                            ~38 MB for per image for 4 bands in separate
AREAS

All bands 4km        ~46 MB for all 5 bands at 4 km in one AREA
--
Dee Wade
McIDAS User Services and SSEC Data Center
Space Science and Engineering Center
University of Wisconsin-Madison           Email:     address@hidden
1225 West Dayton Street                   Voice:     (608) 263-0527
Madison, WI  53706                        Fax:       (608) 263-6738