Printing CMYK issue

Ben Ja Min

To all printers on this forum - hopefully you can help me out with this.

Why would printing photographs in CMYK cause a ghosting effect, really noticable on faces. We are using an HP 5500 and if we ever need to get past this we have to print in RGB for it to print fine. If a poster doesn't contain a photograph then printing CMYK is fine.

Cheers guys
Could be nothing to do with it, but I find sometimes when printing proofs with a high CMYK coverage on the dodgy office printer I get a ghost image because too much toner is laid on and it gets picked up and put back down on the paper by the rollers. Photos could well produce high CMYK coverage beyond that which your printer can cope with whilst basic CMYK work would have more controlled, chosen, measured tones and values.

Just a thought...