There is no way that gif output can be good enough for publication
graphics. I think you are trying to do something that can't be done.
Gif plots from Ferret are exactly what you see on the screen, pixel
for pixel. You can drag the window to be larger (before giving the
FRAME command), so if you have a 4000x4000-pixel screen then I suppose
Ferret could make a 4000x4000-pixel gif.
The fundamental difference between plot metafiles and gif output is
that the metafiles are vector graphics that *describe* the plot
commands, whereas gif files simply save the pixels you see.
The reason that the metafile plots can be large is because they
contain more information; information that is usually essential to
make a fine-quality plot that can be scaled to any size. (And if you
made a 4000x4000-pixel gif file it would be similarly large). But also
note that gif file size scales as the number of pixels, some of which
will be white space, so the metafile from a simple line plot will
usually be *smaller* than the comparable gif from a large window.
You can make the final result of metafiles smaller by converting
postscript to pdf (usually about a factor of 4 smaller, and also more
portable).
If you really want a 300 dpi gif, several software packages can
convert postscript or pdf to gif at whatever resolution you want.
If your metafile is really too large, typically if it has color-fills
with very high resolution that will not be visible in a printed image,
then perhaps you should regrid the field to lower resolution before
doing FILL. For example, if you make a global map of a 1/10th degree
field, the metafile will be huge and contain details that are useless
in a printed publication. In that case regridding would be useful.
Another simple way to reduce the metafile size in such a plot is to
use SHADE instead of FILL: the blockiness of SHADE will not be visible
and the file size will be smaller.
Billy K
On 10 Mar 10, at 7:26 AM, Ilias Koen wrote:
Good morning,
I am a new ferret user and I am attempting to export a series of
publication quality graphics.
Do you know how if it's possible to output GIFs at 300dpi
resolution or at a pixel size that can pull publication for ex
4000x4000 pixels? From our understanding the .GIF export is connected
to the screen resolution, or there is a maximum resolution that
ferret cannot export bitmap graphics above that limit. We haven't
found any other clear documentation on the .GIF export function for
ferret other than the following
http://ferret.pmel.noaa.gov/Ferret/faq/controlling-the-size-of-gif-output
Any tips or hints on practices people have performed in the past
would be greatly appreciated especially for publication quality
graphics export.
The other command option "set mode metafile" produces a PLT file that
is pretty large, we're wondering if there's good method to use less
space per image.
Are there any other methods to export graphics via ferret other than
the two mentioned above ?
Thanks Ilias Koen.