Hi there.
Love paint.net.
I know tiff is a bastard child here.
But, it does has its uses for many of us.
So, I thought it would be usefull to let you know that pdn saves tiff files that are not opened in several other packages.
For my tests I use GDAL [1] which is a set of tools that use the libtiff library [2] to open, describe and convert tiff images.
I get this error message when using a tiff produced with paint.net:
ERROR 1: TIFFReadDirectory:Incorrect count for "SampleFormat"
Also this image does not open in Adobe Illustrator. It does not open in GIMP too. Error messages are:
TIFF image Message
Unknown field with tag 33550 (0x830e) encountered
TIFF image Message
Unknown field with tag 33922 (0x8482) encountered
TIFF image Message
Unknown field with tag 42112 (0xa480) encountered
Maybe you will consider making TIFF at least a working format, or honestly remove it from your write supported format list.
Thanks again for the outstanding software pdn is!
Duarte
[1] http://www.gdal.org/
[2] http://www.libtiff.org/