Step 1: Know how each print is made:
In a discharge print, the fabric is first dyed in a solid colour. A chemical then removes (discharges) the colour in the design area.
In a blotch print, the ground colour is printed over the surface with a roller or screen, and the motifs are left out or printed in other colours.
Step 2: (a) Identify a discharge print:
The ground is dark and the motifs are white or lighter, because colour has been taken out of the motifs.
The design looks the same on the front and the back, as the colour is removed through the cloth.
The edges of the motifs are often slightly rough or show a faint halo.
If a coloured design replaces the removed colour, the motif is bright on the dark ground.
Step 3: (b) Identify a blotch print:
A large area of the fabric is covered with solid printed colour, and the motifs are in the white or light parts.
The back of the fabric looks paler than the front because the colour is printed on the surface.
The colour in the large printed areas is flat and even.
Final Answer:
Discharge print: dark ground with white motifs, and the design shows through on the back. Blotch print: printed solid ground, and the back is paler.