The channel test: find out which Epson tank prints which colour in 5 minutes

What the test prints

One numbered block per physical channel, sent raw — no colour management, no white generation. Block 1 is the first row of the ink table, block 2 the second, and so on. On film both colour and white show, which is why you print it on film, not on paper (white on paper is invisible).

Reading the result

• A block came out white → that tank holds white. Set its row to White; the RIP moves it to the white layer automatically.
• A block came out a colour → set that colour. Magenta printing where cyan is expected means the kit swapped the tanks.
• A block printed nothing or very faint → the channel is clogged or empty. Run Head cleaning, then Nozzle check, refill if needed, and print the test again.
• Two blocks printed the same colour → both tanks carry it. Decide which one should be white and set it.

Let the app do it

In ZoroPrint RIP, Printer tab → “Wrong colours? Diagnose”. Pick what each block printed; the app rewrites the mapping, flags clogged channels and warns you when a colour is missing entirely (no yellow makes black print purple, no magenta turns skin grey). If your kit matches one of the usual layouts — white in M + C or in LC + LM — just pick it under Printer › Ink settings › Inks in the printer; Diagnose is for everything else.