Many thanks to all who came to my aid with ImageWarp.  For my particular
situation it appears that Mark Jones' explanation seems to fit the best.  I
had in fact reduced the number of colors in my image in an effort to manage
file size -- I suspect that is where things started to go wrong.

Mark Jones:


I've had a similar problem, it seems to occur when there are very few
'colors' in the image. It appears that the ImageWarp extension defaults to
a color ramp of at least 256 colors, so when there are few image colors
they all end up at the same end of the ramp. What I've been able to do is
edit the image legend and manually change the color map for each individual
color. With images I've warped with a large number of colors (greyscale or
color), I haven't had this problem. Hope this helps...

Don Sluter:

As I recall, this has happened a couple of times when I was warping Black
and white Tiff files.  I opened the resulting tiff file in photoshop, and
played with
the brightness settings.  I think that you can also play with the color ramp
and get a viewable image.  You may want to save as a jpg instead of a tiff.

Hth,

Don

Lance Morris:

Hey Joe;
 sis you copy/rename the world file over as well? I am
not certain if theat will make a diff. I hope this
helps

Ian Reid:

Joe,

Yeah I recall something like that.  It was due to operator error in my case.
Make sure you are entering the coordinate pairs in the right sequence, and
calculating the RMS at the right time.  In my version of the extension the
"Help" is broken.

I can't remember if imagewarp allows you to manually enter coordinates.  If
so, you may (or may not) have to use negative longitudes for west of
Greenwich.

Good luck,

Ian


Russell Sprague:
joe,
yes i have the same problem. i convert the tif image to a jpeg image then
run image warp. i also save the referenced image as a jpeg. if you need it
as a tif image, you can resave the jpeg image as a tif.
hope this helps,
russell sprague