I was going to point out that you can upload tiff files to this forum, they might not be displayed in most web-browsers but they will be downloadable from the attachment link.
However, it doesn’t seem to work with tifs written from ImageJ, strange. The image generated below from SPC image uploads just fine.
If I try to upload a tif from ImageJ on the other hand I get
"Sorry, but we couldn't determine the size of the image. Maybe your image is corrupted?".
Did you get the same error @mrpargeter?
Edit: This seems to occur both with images generated in ImageJ and images opened and saved as tiff in Imagej (the sample provided above no longer uploads if it is first opened and saved as tif in IJ).