Because the shirt is black, you need a white background paper to show any white (solar flare, words, etc), unless you know a printer that prints white??. This was the second run. I used the iphone wallpaper text on the back of the first shirt and realised you couldnt read the text as the very dark grey text (white/clear text interspersed with black ink flecks) couldnt be read. At that point I realised I HAD to use a white paper (dark t shirt transfer). But using up four A4 full colour (mostly black) images tends to where down the ink, thus it appears grey. My thoughts are that a grey shirt would look better... but who the heck wants grey?....