Phaser 7800 not print correct colours from Photoshop (blue is purple)

[SeoulGal]

Hi, thank you for your reply. We've been busy moving house so haven't been able to reply before. We have fiddled around with settings and it's now printing Royal Blue as a sort of dull dark blue. We know it's capable of printing all colours because of the test sheet that prints when you set it up. The image is set to RGB within Photoshop. Changing it to either Lab Color or CMYK just makes it purple again.

Does anybody have any other suggestions please? It's something I've never understood about printers. Surely a set Hex number should always be the same no matter what printer it's printed on. Just as 00000 is always black then surely any other number should be an exact instruction to a printer for a specific colour. 

This is causing us huge problems as our customers expect to get a certain type of blue when they request it. Many thanks for your help. :)

[Joe Arseneau]

Post a screenshot of your print window in Photoshop please, because if it is set to Printer Manages colors then it should not be making purple from Blue. ICC profiles should not be necessary at all unless you are letting Photoshop decide on colors.

[SeoulGal]

We have been having more and more problems recently with printing colours that are as on screen. Initially with greys. We are now unable to print anything in blue. We print greetings cards on 300gsm smooth ivory card and all our work is done through Photoshop. We have tried every setting we can think of. Printer drivers are up to date and have been reinstalled, the OS system on the Mac is the latest. We've tried letting Photoshop control the colours and we've tried letting the printer control them. We've tried CMYK and Photo Lab settings etc. Although there are differences in each setting, the end result is still wrong.

We can print fine from Word. If we do a calibration on the printer there is a great blue in the resulting printouts. But we cannot get this from within Photoshop. Does anybody have any ideas on how to do this? 

I don't know the first thing about icc or any other abbreviation and would need really simple instructions to explain what we need to do. I've researched online and have yet to understand anything that might possibly be a solution for us. I really hope that somebody out there can help us. We're pretty sure it's a Photoshop settings issue. Thanks.