Problem with online printer- color C100+M100 prints cobalt blue??

[roger agau]

I recently had an issue with an online printer doing a dye sub table cover for me. I made the color C100+M100 expecting to get a dark purple, as is shown in the Pantone CMYK formula guide. When I received it, it was a cobalt blue color. Here is the response I received from the company:

One of our representatives has responded to your claim for job A613220-01/(171792) please see below.

Hello, After reviewing your claim ticket we will be unable to reprint this order. 100% Cyan and magenta is the composite for a blue print. We sincerely apologize for the inconvenience but since we do not offer color matching and the values are not correct for a purple print. Thank You

I called them to discuss and they 100% said I was wrong, and that this CMYK formula will print blue. I first politely asked them what reference book they were using to draw this conclusion. They told me they do not have any CMYK swatch books in their facility since they do not "color match or print Pantone colors", but that they do 5000 jobs per day, and nobody else has complained about the color of their prints. I tried to explain to them that a CMYK reference swatchbook has nothing to do with "Pantone" colors which I think they were confusing with spot colors. I became increasingly agitated by the prepress manager's lack of knowledge and insistence that C100 M100 prints blue. In all my 35 years in the industry, it is a known fact that this color may appear blue on the monitor, but when printed it comes out purple. Most of the time, my clients complain when their CMYK blue builds come out to purple. I tell them the rule of thumb that your magenta should be 30% less than the cyan to avoid a purple shift.

Either everything I have learned in the past 35 years is completely wrong and all my CMYK swatchbooks are incorrect, or this company is clueless and needs to get a basic education. THOUGHTS???

[kglad]

looks blue to me:

[roger agau]

Are you referring to the color on screen or when printed? Of course it looks blue on screen, but if you print it it is purple.

[kglad]

i wouldn't call it purple, but i'll look for another forum where there may be 'color' experts.  i'm not one.

[moved from Adobe Creative Cloud to Color management]

[D Fosse]

Here's how 100-100-0-0 looks in two standard CMYK spaces:

[jdanek]

The color on the left is what I am seeing on my laptop monitor.  No way 100%C + 100%M is blue.  I am seeing a purple, a color it should be on screen and in print.  I can't understand how anyone would get blue on screen and purple in a print.

[jdanek]

I am using CMYK = US Coated Sheetfed SWOP v2 in my color settings.  The print vendor is a poor excuse of a print vendor.  I would not use them in a million years.  Plenty of good alternatives out there.  Not sure where you got "5000 jobs per day".  That is 625 per hour in an 8 hour shift.  That is 10+ jobs per second.  Sorry, but they are full of #!?T.

[Test Screen Name]

The CMYK swatch card from Pantone is not any kind of universal standard or consumer reference. It tells you what colours may look like if a print vendor happens to buy Pantone approved inks or equivalent, which is one of many choices they might make, and uses them in compatible press conditions. A modern printer won't care about that stuff and nor should you; they should accept tagged RGB Probably as PDF/X-4.

At least, if you feel you must design in CMYK attach a CMYK profile to say what colours you are thinking of. I think your knowledge needs a major update for the modern use of colour, or careful prevetting of print vendors to make sure they are working in the same constrained view that CMYK is some kind of standard defined by a swatch book. Better, bin your CMYK swatch books 

[Stephen_A_Marsh]

Also here:

C100+M100 dark purple prints blue from online trade printer doing dye sub. job