rgb to cmyk

[1leonchen]

how do u convert rgb pictures to cmyk for your printer. i keep getting colour shifts every time i print a rgb file i am using flexi 8.1 with a 6 colour mutoh falcon. i have cs3 suite and corell x4

 

[SignBurst PCs]

how do u convert rgb pictures to cmyk for your printer. i keep getting colour shifts every time i print a rgb file i am using flexi 8.1 with a 6 colour mutoh falcon. i have cs3 suite and corell x4

Your RIP software will (and is) doing the conversion.

Your color shifts are probably due to profile issues or lack of monitor calibration.

At least that is my guess.

 

[iSign]

Where are the RGB files coming from?

RGB color space has a wider gamut, so your customers can give you colors that are physical impossibilities to ever achieve on a CMYK printer.

Have you just sent RGB file to your printer, instead of converting it first?
I only send RGB files, but most of them started as CMYK, when they are from my own designs.

I worry less about how my color looks on my monitor, & more about my test prints. I am not a color guru, like I would be if I were in the fine art reproduction business... or even the wholesale digital printing business... I don't calibrate my monitors, or make my own profiles... & I'll bet I represent the typical workflow of the vast majority of sign shops.

I have absolute respect for folks that understand that stuff... but I have had almost NO issues with critical color matching concerns that interfered with getting a job out & a satisfied customer.

I use the same procedures most of the time & have produced color charts using those procedures, & between the chart & the use of my chosen procedure... things are generally predictable enough for the level of perfection I lead my clients to expect.

I tell customers color matching is an exact science that may or may not always be possible with a CMYK printer, running outdoor durable inks... and if they want fine art reproduction, they have come to the wrong place.

If they want outdoor signage, there will be variances in the appearance of color, depending on the ever changing outdoor lighting conditions, as well as the inherent nature of color fading that does occur, even on 5 year durable print work. The variances of my color matching abilities are generally no more than those imposed by unavoidable environmental conditions, and are therefore a moot point.

 

[Tony Teveris]

Your colors are shifting most likely because your color management setups in cs3 or Corel are not the same in your RIP.

Not sure your RIP app has ICC device profiles but if it does you want to use that as a "proofing" profile in the design apps. Doing this you will see waht you hope to print via the RIP in your design program.

 

[1leonchen]

the pictures attached are one of the examples. top is the printer,lower part is the original file. i am using mutoh falcon outdoor 6 colour with flexi 8.1 as rip.

 

[zmatalucci]

tongue lashing in..5--4--3--2--

 

[1leonchen]

tongue lashing in..5--4--3--2--

 

[Wildpony]

tongue lashing in..5--4--3--2--

Ok, I'll bite. Do you have permission to be printing copyrighted artwork.

What I do is, I have a book I made with all CMYK possibilities in 10% increments printed. I then find the color I want and use that recipe for the CMYK numbers.

 

[1leonchen]

ok hear me out i just did a test print nothing for resale. but most of my client images some times comes in rgb files. i only printed taz as a example. the image was 1200by 900 pixels i only wanted to show the colour shift. and taz i my favourite cartoon caracter.

 

[iSign]

...so, that looks like a 3 foot, or 4 foot wide Taz print... are you telling us you printed that just to show us the problem?

how about printing 3 INCH wide prints when you have a problem, and then try some of the suggestions and print another 3 INCH test

Where are the RGB files coming from?

Have you just sent RGB file to your printer, instead of converting it first?

 

[bob]

What, exactly, are you doing? Is this a bitmap or is it a vector collection? Are you trying to make a CMYK bitmap out of it and then print it? To what are your rendering intents set?

 

[Dave Drane]

So what if it is copywrited.. A nice print of Taz on the bar fridge in your own bar room for you own use as a one off is no big court case deal. I get a bit sick of all this litigation B/S..

 

[iSign]

geez Dave, you sure you're sick of it... you're seeing a conversation that never even happened except post 8 guessing what post 6 was joking about... but you go right back and make that into the topic yourself

 

[1leonchen]

its a rool of two feet banner cost like 15 dollars. printed at 360 dpi by 360 dpi,its a rgb file i took off the internet.all of my files are either vector or eps. i created every thing eps. but i get the same problem espically when a client wants a picture that they took with a digital camera.
i got a better result when i changed the graphics card and went dvi conection.
i am not that vast a designing and i am curently learning the programs. when it comes to application or cut vynil thats me.but full colour is a learing curve for me