I just expirimented with putting a pencil drawing on a shirt.
My sister had a pencil sketch drawing done so I did the following:
1. Scan the image, used the default scanner settings which produced a jpg file.
2. Used a DTG Printer to print onto the shirt.
The end result is just awesome! It looks like someone took a pencil and drew right onto the shirt!
If anyone is interested you can email me the drawing and I'll print you a sample.
Here are some pictures of the finished Shirt