Convert document to CMYK

[#1]

I have created a 16 page document that is going to a professional printer. This my first job that will be printed professionally. My document contains a number of photos in psd format with RGB profiles and swatches both in CMYK and RGB format. 

The printing company has specified that they need the document to be sent in CMYK.

What is the best way to convert the document to CMYK and also what other tips could you give me to achieve the best possible print quality?

Many thanks.

[#2]

I have created a 16 page document that is going to a professional printer. This my first job that will be printed professionally. My document contains a number of photos in psd format with RGB profiles and swatches both in CMYK and RGB format. 

The printing company has specified that they need the document to be sent in CMYK.

What is the best way to convert the document to CMYK and also what other tips could you give me to achieve the best possible print quality?

Many thanks.

[#3]

Presumably you're sending them a PDF, select PDF/X-4, normally single pages, (not spreads), tick Crop Marks, and Use Document Bleed Settings – but ask the printers to confirm the spec, they should do the conversion.

[#4]

In addition to what Derek said, "CMYK" is a device-dependent color space. So you must how the colors should "look", which is described by a ICC color profile. You should talk to your printer about the correct profile, so you can do the RGB -> CMYK conversion during the PDF export correct. If you don't know that you can stop here.

In theory there is a different profile for every paper-machine combination. But there are some industry-standards like PSO coated/uncoated v3 in Europa for offset printing. Not sure what the standards are outside of Europa (GRAcol? SWOP?)

[#5]

If the printer wants an all CMYK PDF, they’ll need to provide you with their press profile and that profile needs to be assigned to your document Edit>Assign Profiles. Even if you export with the default PDF/X-4 preset which leaves color unchanged, you’ll need the correct CMYK profile assigned to your document, because the CMYK profile handles the preview of your native ID CMYK swatches and is set as the PDF’s Output Intent, which handles the preview in Acrobat.

PDF/X-4 leaves transparency effects live (not flattened) and color unchanged. With placed RGB images you’ll need to turn on Overprint or Separation Preview to see how unprintable RGB colors will print. To get an all CMYK PDF/X-4 set your Output>Color Conversion to Convert to Destination and the Destination to Document CMYK.

PDF/X-1a flattens transparency and forces all process color into document CMYK.

[#6]

Thank you all.

The printer has specified CMYK only. So my question to them should be what is the printer's ICC press profile?

Also, regarding downsampling and compression, do I leave it at default, bicubic downsampling to 300 pixel per inch for images above 450 ppi? Or is it worth changing it to downsample to a higher ppi?

Many thanks.

[#7]

Yes, the question is what profile would they use to make a CMYK conversion. If they can’t be clear about the profile make sure to get reliable contract proofs—if this is your first print job, you probably want proofs in any case .

You can leave the default compression unchanged.

[#8]

The printer has to provide you with the Output Profile. Where are you origninated, here in Germany and Austria most printer work nowadays with ECI300, even if it is not the latest standard.

[#9]

Hi Rob and Willi, I am in the UK. 

Yes, I am sending the document for a proof print first. 

I have a completely different day job, but do graphic design as a hobby and my company has trusted me with this very important document for marketing purposes so I want to make sure it will come out perfect.

[#10]

If you mean a "wet proof", depending on the process, it can be expensive, so check the price first. If you have a short print run the proof might be a similar price to printing the actual job!

[#11]

Then the default US Web Coated SWOP is probably not going to be the best choice. Also your monitor profile affects color mangement—are you working with a calibrated and profiled display? CMYK and RGB color gets converted into you system’s monitor profile for the soft proof display.

[#12]

The printer got back to me with the request: please convert to PDF X/1A. 

I have inserted a screenshot of the export screen. Is this the correct setting? Would I have to change anything in Output?

Also, sorry if this is a stupid question, but how do I know that the document has been converted to CMYK?

 

[#13]

but how do I know that the document has been converted to CMYK?

The PDF/X-1a Standard forces all process color to be converted to CMYK—as long as the Standard isn’t changed the exported color will be CMYK. The default uses your document’s assigned CMYK profile for any conversions.

[#14]

Also you can check the objects’ color modes in Acrobat via Output Preview>Show