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Thorsten

Change JPG Photo from RGB to CYMK, how?

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Hi

 

I have made a flyer with a couple of pics taken from my digital camera, those are in RGB.

The printing guy now told me to put the pictures int CYMK.

 

First I didn't know how to do this, (and maybe I still don't), but I selected in Preview Tools>match to Profile and seleced CYMK.

And first it looked like it worked, the picture changed a bit I adjusted the colours so it would look good again.

And then I saved it as a JPG as a diffrent file name.

And thats where it all went wrong, after it was saved it turned black purple for some reason, and Preview crashed.

I have since tried this many more times, and Preview does not crash anymore but the red, black result is always the same.

I tried to save the picture in other formats tiff, PhotoShop, with Photoshop (file Format also from Preview) I got the same result.

and with tiff, the picture did not keep the adjusted colours.

It at least saved the pciture properly but not the adjusted colours, at least that is what it looks like, as it looks like when I first selected match Profile CYMK.

 

I hope somebody can tell, me what I am doing wrong or if Preview, has some big programming error or what.

 

hanks

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I don't believe Preview is capable of changing the colour space of an image. I think what you did was assign an CMYK colour profile to an RGB image. I think you will need an App like Photoshop to actually convert the image to the CMYK colour space.

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Open the file in photoshop and choose image->mode->CMYK. Then make sure that any colors you use are also CMYK. So if you are using indesign or illustrator to design all of the swatches must be CMYK. Finally if you don't know how to change to CMYK you likely don't know anything about bleed and live area. Make sure that your flyer has .25" of overlap in all directions and that nothing critical is closer than .25" to the edge. This way when they cut it and the individual pages move around you won't off anything critical and you won't get any white edges.

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Thanks alot for the help.

Well I am using Pages.

But it seems to me I should have been using some Adobe product.

Which is knd of annoying me I just wanted to make a simple flyer for my club and we wanted to get Professionell Printing.

But to get professional printing it seems like I have to use Professional Software.

 

Well I have downloaded the Photoshop trail version, and then wanted to do some adjusting in preview afterwards, and I got the same results. (All red and blac, now I know what it is the colours are inverted.) Which is most lily something do do with CMYK and RGB since CMYK is technically the opposite of RGB, so I am quite sure there is something wrong with Preview.

Anyway I have now just changed to CMYK in Photoshop and then put a filter above the picture in Pages, I hope this will be ok for the printing guy, will have a talk with him on monday.

 

Open the file in photoshop and choose image->mode->CMYK. Then make sure that any colors you use are also CMYK. So if you are using indesign or illustrator to design all of the swatches must be CMYK. Finally if you don't know how to change to CMYK you likely don't know anything about bleed and live area. Make sure that your flyer has .25" of overlap in all directions and that nothing critical is closer than .25" to the edge. This way when they cut it and the individual pages move around you won't off anything critical and you won't get any white edges.

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How about just hiring a designer? Probably cheaper than buying creative suite plus they will have the experience to get the work done the right way.

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How about just hiring a designer? Probably cheaper than buying creative suite plus they will have the experience to get the work done the right way.

 

Well your absolutely right, if this would be a business but we are running a non-profit organization, so there is never enough money, and this flyer is anyway only intended to be amateurish and it looked great in Pages to be honest we were absolutely happy with it.

 

So Basically I am actually annoyed at the Apple Producs for not giving m the ability to convert to CMYK, I mean every printer, prints with that right?

 

But wh I still don't understand why does anybody work with RGB when in the end you anyway need the picture to be in CMYK?

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But wh I still don't understand why does anybody work with RGB when in the end you anyway need the picture to be in CMYK?

Generally speaking...

 

Computer = RGB (that's the way computer monitors work)

Print = CMYK (that's the way printers work)

Video = YUV (that's the way video cameras/tape/monitors work)

 

different colour spaces for different applications.

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I've never really understood ColorSync, but it's my understanding that it makes that conversion so what you see in RGB on a screen comes out correctly in CMYK on the printed page.

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Generally speaking...

 

Computer = RGB (that's the way computer monitors work)

Print = CMYK (that's the way printers work)

Video = YUV (that's the way video cameras/tape/monitors work)

 

different colour spaces for different applications.

 

I guess so, but I am wondering if this is really necessary and it just developed this way, or if it would be possible if some body would implement it, that they all use the same color space.

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Just a thought - does it really matter? Surely, so long as you are happy with the final result, that's what really matters! Personally, I often take what these so called "experts" say with a pinch of salt!!

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I guess so, but I am wondering if this is really necessary and it just developed this way, or if it would be possible if some body would implement it, that they all use the same color space.

It has to do with the technical details of the way equipment works. For example, printers and displays need different information to produce results that look similar to us. But I agree, it would be nice if this stuff were more transparent to the user...

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I guess so, but I am wondering if this is really necessary and it just developed this way, or if it would be possible if some body would implement it, that they all use the same color space.

No it's not possible. Offset printers can not reproduce the range of color that a device with luminance can. Send me a private message and I can help you get your files going.

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Actually, you might be able to do this conversion using the Quartz Fun House in the OS X Developer Tools or even though an Automator action. I know that Automator takes advantage of Core Image and can do conversions from jpg to png or tiff.

 

I would give that a shot and if it doesn't work and you don't want to shell out the cash for Photoshop I would have a look at Pixelmator. It is cheaper than Photoshop but does much of the same things. It will even open and save Photoshop documents.

 

Hope these ideas help.

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