Proofing Prepress With an InkJet Printer
♫ Monday, December 27th, 2010It’s common nowadays to produce positves for screenprint on a high-end inkjet printer. The inkjet printers are standard issue, usually Epson manufacture, with 6,7 or more inks. It is possible, with the correct set-up to run high quality proofs from these devices. Firstly, a couple of caveats, with most RIPs you can have halftones which reproduce the halftones of the imagesetter or contone which gives solid colours. You cannot mix the two, so if you have a four colour job with a spot colour, that spot colour will be halftoned or the halftones will be represented as tints. In addition, spot colours cannot be easily reproduced by process colours (CMYK) because if they could – you wouldn’t need spots! You need to be clear as to the intention of the ‘proof’, it is usual to halftone the whole thing and attach a disclaimer about spots because these are controlled by the inks you use and are therefore less susceptible to variation.
Start by choosing a four colour (CMYK) mode on the printer, we want to exclude Light Cyan/Light Magenta/Oranges and Greens, these will just interfere with the proofing process. Linearise the output of the printer and get the printer profiled in this mode. Remember, the press inks are probably fairly close to Pantone CMYK inks whereas inkjet inks are deliberately made brighter to allow richer colours and a wider colour gamut to be acheived. The proof should now show a fairly accurate representation of the final job. It should be noted that the CMYK values on the proof may be different from those on the press output. 100% cyan on the press may require something like 90% cyan on the inkjet with a little magenta and yellow to match the colour.
