HELP! cmyk?

back alley

back alley

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moo informs me that they print in cmyk and that the file i sent for printing was an rgb profile...and that is why my postcards are greenish and very warm in colour...they would more than happy to reprint my cards if i send them a cmyk file...

huh?

ok, so what do i need to do?
 
back alley said:
moo informs me that they print in cmyk ...
ok, so what do i need to do?
Click to expand...


Step 1: ask them what CMYK ICC profile you need to use.
Step 2: download and install that ICC profile so that your image editor (e.g. Photoshop, ...) can see it
Step 3: Open you image in your image editor, provided it supports both RGB and CMYK.
Step 4: set your editor's color management appropriately so that it uses the ICC profile from #1-2 for RGB>CMYK conversions.
Step 5: convert the image to CMYK. In PS this can be done on the Image>Mode submenu.

You may have to deal with finding another image editor if your editor of choice doesn't support CMYK. Many "photo only" image editors lack support for CMYK. That's one of the simplifications in Photoshop Elements while Photoshop CC & CSx all support both along with Lab. color space.

You'll likely see some color shift after the conversion. If your image editor has good preview ablility you should be able to tweak things reasonably well. The gamuts for RGB (whether sRGB, Adobe RGB (1998), ProPhoto RGB, ...) and CMYK are different and perfect conversions sometimes are impossible.
 
My advice is to always do the CMYK conversion last. Some colors will look really wanky on an RGB monitor after converting to CMYK (which is normal), and trying to tweak them after conversion will probably make things worse unless you have a lot of experience with this stuff.
 
did some reading...i use pse 13 and it does not convert to ckmy...found some free software online but not for mac...
might convert to b&w for an easier fix...
 
Our press (newspaper) can convert RGB to CMYK. Most digital presses can handle that. My experience, though, is that the result can be unpredictable, so I do the conversions myself. Apparently the OP's printer needs a specific cmyk profile.
 
Joe,
My guess is there's a few (OK a lot) of folks here who have PS or other software that can do your conversion. Pick one of us and send that file over.....you'll get a cmyk back.
 
If you have a Mac, you can do it in Preview...

Edit: Never mind since Preview is only showing RGB profiles to select from.
 
in Mac land, Pixelmator ($30) can do the conversion.

More to the point - they didn't show you a proof before printing anything? They didn't tell you they needed CMYK before printing? A bit odd. Sounds like an excuse for a poor job. It's been years since a printer demanded a CMYK. For "critical color," sure. High-end printed catalogs, art and coffee table books with 100s of images, but for simple job (A business card? A post card?) with "pleasing color?"

Ok, make the conversion, give them the file they want. But I still would not trust them - ask for a proof.
 
TRy to learn on CMYK.

TRy to learn on CMYK.

After you do the conversion and profiles...you´ll still have to learn to work with each colour and set the proper % on each channel.

for instance never go up to 100% in black or lower cyan in the parts of a face etc. MAking the exact balance for output is crucial. Each channel C M Y K plays a role on the whole print.

Remember RGB are light colours and CMYK are material colours, and are totally different things.

Try to check for differences on teh web for sure there is some website taht can explain this important thing.

regards
 
MaxElmar said:
in Mac land, Pixelmator ($30) can do the conversion.

More to the point - they didn't show you a proof before printing anything? They didn't tell you they needed CMYK before printing? A bit odd. Sounds like an excuse for a poor job. It's been years since a printer demanded a CMYK. For "critical color," sure. High-end printed catalogs, art and coffee table books with 100s of images, but for simple job (A business card? A post card?) with "pleasing color?"

Ok, make the conversion, give them the file they want. But I still would not trust them - ask for a proof.
Click to expand...


Every quality printer I've wofked with since the 70's has wanted cmyk files. It's the standard of the industry and they most likely assume their clients know what they're doing. I don't know anything a out Moo but they probably are t in the business to hold folks hand through the process.

If you want accurate color you need a proof but you need the knowledge to interpret it under standard viewing conditions and how to spec changes in the terms the printer understands such as % of a specific color change. You can't look at your proof under tungsten or cfl light and say take a tiny bit of cyan out and add a smidge of yellow. You'll need to say take x% cyan out and add x% yellow.

Printers are only as good as the information you provide for corrections.
 
The profile for the press takes into account the dot gain on that specific press, pale and ink. Every press, paper and ink have a unique personality that you have to correct for.
 
Every commercial printer in the world uses CMYK. In fact, there is no such thing as RGB printers. RGB is purely an on-screen colour medium. (As someone said upthread, RGB and CMYK use completely opposite methods of dealing with light to produce colour. RGB is additive colour, CMYK is subtractive colour.)

CMYK printed photos are always going to produce a different rendition of colour to RGB – usually 'duller' (especially orange and green), as it is not possible to reproduce the same colour on paper, as it is on screen.

With expensive inkjet printers, many of which use 8 or more inks, it is possible to achieve very good results, even when printing RGB documents on them. But they are still just simulating RGB.

With commercial printers, who print hundreds or thousands of copies of a document on large offset-litho machines, 4 inks (CMYK) is normal. (There is a high-end printing process, called Hexachrome, that uses 2 extra inks – orange and green – as well as CMYK, but it's not cheap).

That's why it is important to convert to CMYK and making any final adjustments on calibrated monitors before sending files to press. And yes, colour profiles and so on can also be important. The best advice I can give, is to always check with the printer before sending any files. They are generally the experts in this case, not the photographer.
 
Images shot with digital cameras are normally set to a default RGB color space (sRGB is the most common) and this is perfect for MOO. We’ll convert them to CMYK using our own profile, which compensates for the paper and finish of each product.
Remember: where possible, preview your photographs in CMYK. Colors displayed on screen will always look much brighter than the final printed products.
If you have a color calibrated screen, and would like to preview or upload your images in the same CMYK colorspace MOO uses, we recommend the following settings: Coated GRACOL 2006

This is what MOO says on the help page. Why then didn't they just do the conversion of the file?
 
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