You could send us a tiff file that seems to work and another from imagemagick that does not seem to work and we can examine the difference. I've had some problems obtaining two images that can be compared, but I now have two 8bit images, one converted with ImageMagick and one converted with another ...
-channel RGB does nothing in your command. Perhaps you meant -colorspace sRGB (RGB in very old versions of IM), although your image is already RGB as opposed to CMYK. Try one of these and see if they work. convert image.jpg -colorspace sRGB -type palette -depth 8 -compress none image.tif convert ...
I'm trying to compress images from 24bit to 8bit. They look fine until I open them in Microsoft Office Document Imaging, where they are green. This is the command I run: convert C:\Users\******\Orginal.TIF -type palette -auto-level -channel RGB -depth 8 C:\Users\******\Compressed.TIF Here's an ...