A terrible mistake! RGB instead of CMYK

[johan1]

Hello people!

I'm new to this forum and sure not an 'advanced' Photoshop user yet.

I am making some labels for some fireworks cakes. I have to do circa 25 cakes. They all have the same style, but with a different image on the front and some other minor differences. I had a great layout with dark-red backgrand and contrasting yellow details. When I was around the 8th label, I totally remembered I was being really dumb: I was working in RGB color profile instead of CMYK!!

I tried to make it CMYK via ISO coated 300% v2, I looked around on the internet and they said that's a good choice... I don't know what they print with in China, so I don't have much of a choice. Still my nice label gets an ugly brown look. I've tried lot's of things with layer styles, but it just won't work out fine. I know RGB is much brighter and saturated then CMYK, but there has to be a way to let my labels at least look a little bit like I head in mind.... I'm really desperate since the labels have to be printed at the begin of june. What if I keep them RGB and print it?

In the link below I have a ZIP file where you can see a RGB and CMYK file. It's kinda messy with layers and stuff, but I really hope someone can look at it and give me tips what to do!

 

[johan1]

I see that as a new member I can't place links yet... It's a little against the rules, but since it's too big to upload via the forums so I hope this will do:

www [dot] mijnbestand.nl/Bestand-PUEJBZWDS448.zip

 

[iDad]

Maybe you can take a screenshot of both pictures side-by-side so we can see the difference but I also think you may be able go from RGB to CMYK, without that much of a problem if it's one item that is throwing everything off maybe you can copy that item and apply the color needed in CMYK and then bring it back over to the document that you just switched over from RGB if you can understand when I said. even I'm scratching my head on that one

 

[ALB68]

I'm scratching my head wondering why it has to be in CMYK anyway. Most commercial printers today expect to get and are used to everything being in RGB and they do their own conversions (much better than you. Did they give you specific instruction to create it in CMYK color space? If not, ask him what he needs. You may make a bigger mistake here trying to do this.

If these are going to be printed on a desktop setup, you send the file in RGB and the printer (hardware) makes it's own conversion. I have a Canon Pro100 and it does exactly that. I also have a wide format Canon that has an Adobe plugin that allows you to send RGB files to it.
So, it should not be a huge problem.

(Oh, and by the way, it is not RGB profile...RGB and CMYK are color spaces or some refer to as color models.)

 

[dv8_fx]

ALB... CMYK is the preferred format here in Asia and almost everywhere for preparing CMYK color separation films for use in offset printing.


Johan....

I'm in Asia and most of the printers I go to here in my area can assist in converting your RGB work image to CMYK for processing. But I have to include a printout of what the actual colors should look like. Or at least a CMYK electronic image.

It is an SOP for them to do a test print with the film they produce for the client to see before the client gives the approval for final printing.

I'm not sure how they do things in China, tho. It may help if you can contact them to see if they can do the conversion while maintaining the colors you need. And if they can send the test print for you to judge their conversion work.

 

[dv8_fx]

In addition, you may have to turn on the PS CMYK color management display setting to accommodate the viewing of a CMYK work document. Give it a try to see if there are any significant change in viewing the true colors.

 

[ALB68]

The OP mentioned China, but did not say where he was. A bit confusing. I don't know why it isn't a requirement or at least a common courtesy to say what country your in. My mind reading skills are poor.

ALB... CMYK is the preferred format here in Asia and almost everywhere for preparing CMYK color separation films for use in offset printing.

"Johan....

I'm in Asia and most of the printers I go to here in my area can assist in converting your RGB work image to CMYK for processing. But I have to include a printout of what the actual colors should look like. Or at least a CMYK electronic image."
(My point exactly) A good procedure I suppose just seems a bit antiquated.


Johan....

I'm in Asia and most of the printers I go to here in my area can assist in converting your RGB work image to CMYK for processing. But I have to include a printout of what the actual colors should look like. Or at least a CMYK electronic image.

It is an SOP for them to do a test print with the film they produce for the client to see before the client gives the approval for final printing.

I'm not sure how they do things in China, tho. It may help if you can contact them to see if they can do the conversion while maintaining the colors you need. And if they can send the test print for you to judge their conversion work.

 

[dv8_fx]

LOL... an innocent oversight by the OP.

(My point exactly) A good procedure I suppose just seems a bit antiquated

Not at all antiquated. Even in these modern times, a lot of established printing companies still use the process in printing well-known magazines and other works. An ageless procedure, I'd say.

 

[iDad]

So confused CMYK, RGB, antiquated,............. what to do ........what to doView attachment 32407

 

[Tom Mann]

As was correctly pointed out, CMYK is in common use everywhere in the world among large volume printers, particularly, offset press printers, and will almost certainly remain so.

However, among small volume printers, this is not the case, at least here in the USA.

Because the clientele, and even the staff of many small volume shops typically have absolutely no experience in anything except sRGB, no experience in producing CMYK or spot separations, and not a clue about which of the zillions of CMYK profiles to use, soft proofing, line screens or any such matters, in the last 10 or so years, such shops have gone over to RGB as their only / strongly preferred input.

If they didn't do this, their mom-and-pop / school project / business card / poster clientele would vote with their purses and take their business somewhere else.

At street corner printers like Office Depot, their equipment is often little more than glorified ink jet technology, and so is dealt with by exactly the same method you send a file to an inkjet connected to your own computer: You work in RGB, and the printer driver software invisibly makes the conversion to CMYK after you tell it what paper and inks you are using. In contrast to an offset press, if you send such a small volume shop a CMYK file, they will either not accept it, or they will almost certainly do a bad job printing it.

The real problem occurs with some small volume print shops that because of stupidity or because they want to pretend to be more knowledgeable than they really are, suggest that they can accept CMYK file input, but no one on their staff has a clue about how to process such files.

If you are lucky, you will get a staffer who actually knows Photoshop, and when they receive a cmyk file will know to "convert to RGB" instead of "assign to RGB", and specify the correct profiles in both spaces.

Hopefully, this clarifies the differences between printers.

Tom

 

[Tom Mann]

PS - The term "commercial printer" may be part of the problem in this thread. The important distinction to be made is between large and small volume commercial printers and the printing method each use.

Both Kinko's and the press that puts out the daily newspaper are commercial printers, but they deal with very different printing technologies and customer knowledge.

T

 

[johan1]

Hello again, thanks for all your reactions! You sure give me a lot to read. Not sure if I understand / interpretate everything the right way though. In my college I've learned to work with CMYK. We make lots of visual oriented reports and posters at school. They say you always have to use CMYK if you'd like to really get the colors you want (and indeed, different prinshops can use different 'color profiles' which have an influence on the printed colors.

I was just a little too enthousiast when I was starting with the labels, what made me forget to use CMYK.

At the moment I wouldn't dare to say what they print with in the far away China, but I guess the person who actually goes to China for the fireworks will know, or can ask for it.

I was just screwing around a little just now, till I came to an interesting thing:

I have RGB PSD files with different layers, I also used different layer styles luke lumosity, lighten color ercetera. When I change the color space to CMYK, each layer individually changes from color. Specially the layers that have a special layer style will change their effect drasticly! If I merge the layers and flatten the image before converting the color space, the difference is almost zero! Just see the image below. The question is,since the difference is almost none, is this really 'converting color space' that the printer will recognize als CMYK, or just Photoshop just say CMYK and are the colors actually pretty RGB... Don't really know how to explain it. I really hope this is a right way to convert them to CMYK. Even if the printer show slightly color differences (what sure will happen), at least all the images have the same red color. If I manually change to CMYK in PS with all different layers turned on, I just can't get the red colored backgrounds in the same color.

 

[Tom Mann]

Johan, as you correctly observed, all bets are off when it comes to the colors of individual layers when you do a color space or profile conversion in a multi-layer PS file. However, I don't understand why you even brought up this possibility because one should always send the printer a flattened file (ie, one layer), albeit with multiple channels.

For example, you might need two channels, say, one for a spot color with a unique metallic ink, and a second for the remainder of a grayscale image. Three channels is obviously the most common, four for a CMYK, various numbers for duo- and tritones, etc. However, why might a printer need to have access to all the adjustment layers that went into making your final product?

With respect to your comment about the screen colors more accurately representing print colors if you work in a CMYK color space, this may be a useful approach if you have very simple needs. For example, this approach could work if every image that you work on only has only one final use, a print by a particular printing technology.

However, if you are looking to the future and are trying to build up a set of images that can be re-used for multiple purposes (eg, web, high quality art print, low quality brochures, different sizes, etc.), you really should perform all of your technical and creative manipulations in a very wide gamut, high bit depth color space (say, ProPhoto RGB) and wind up with a master file that can be easily re-purposed. In contrast, if your master file is a narrow gamut CMYK, you will never be able to satisfactorily turn it into a wide-gamut image.

The issue of the colors "not matching" if you are working in something other than cmyk isn't really a problem. Once you have a high quality master in hand, you can either do a specific color space / profile conversion at that point, or just turn on soft proofing for the particular color profile you are targeting, and tweak for that particular space / profile.

HTH,

Tom M