What happens if you don't cure the shirt after printing?

Photoshop question about printing 4-color black t-shirt?

• I want to enter a design contest for a t-shirt but I don't know the specifics about how it will be printed. I want my design to be on a black shirt (but it would work for a white one too). All the specifications say is that the design should use a maximum of 4 colors. Right now my palette is not huge but it has more than 4 colors because of a photo that has shadows. What would be the best way to prepare this for a t-shirt? Should I use the index color mode to reduce it to 4 colors? (I read that that doesn't work for black shirts) Should I use the number of colors I have now and then split the channels later? Will the t-shirt printer be able to do the work as long as I keep the layers together? I know I haven't provided a lot of info but you know about as much as I know in this case. I would be grateful for any help. I'm pretty familiar with Photoshop for web/print but have never designed a t-shirt before. Thanks in advance!

• Answer:

  looks like you'll print it on screen. Choose 150DPI and RGB 8 bit. So you'll get pallet with 8 bit color (it's around 256 color) you may use it 4 color from them.