Hi baphojunior
I am not too sure but my understanding is that if you have a photo or detailed image (perhaps a landscape or photo)
you would need to convert the image to a vector halftone image and separate the colours into the 4 colour process.
You will then print the image using the 4 colour process, which will allow the 4 colours to be applied to the garment and mix as then are applied to provide the wide range of colours and detail that you would find in a photo image.
Hope this makes sense.