Color Management

[condor99]

I just bought a used C6500 with an Creo ic-304 RIP (actually an Ikon 650 powerpro). I am having problems with skin tones, images are becoming a little over exposed, and with the reds, we see some fine lines.

Does anyone have any tips for achieving nice flesh tones?
Any specific Proper settings on the RIP?
Also, Konica came out to calibrate , but did the off the glass calibration, does it make a big difference from using the Densitometer?

I find that DOT 2 Screening gives the best results. I think I have all the patches and update to date firmware.

I tried out the C6501 and found the skin tones great, but decided on saving some money and getting the C6500. Is there a big difference between the two?
Should I be sending files in CYMK or RGB, does it make a difference?

Any help would be great- thanks!

[random]

There is't a lot of difference between a c6500 and a c6501 but in my mind the c6501 does print better than a c6500. In saying that c6500 prints great!

DOT2 is quite coarse I think and not really used for genral printing. If Konica came out and calibrated your rip it almost certainly wouldn't be to DOT2.

One gotcha that C6500 owners don't get is that all the screens have different calibrations so if you calibrate for one it does not apply to all screens. It goes without saying a spectro will calibrate better than just off the glass.

You need to tell us/me what applications you are printing from before I can help further.

[Setright]

Yes, the print quality shouldn't be that different.

As above, make sure you calibrate the machine and controller for the screen you intend to use. Then calibrate the other screens, so their test output looks like the one you calibrated. For unknown reasons, calibration will affect the gamma offset on the machine, so you can only spectro/glass plate calibrate 1 screen accurately.



I would check the firmware version, from 50 (we just got a version 60) the screen for yellow has been revised, and you can choose old or new. This could affect skin tones.

You might need on-site tech support to follow-up on these two points.

[condor99]

Thanks for the help. Currently, I am using CYMK Jpeg files, designing in Quark Express, and converting the layouts to PDFs. Then taking the PDFS to the CREO computer and printing from that. (I am having problems printing directly from Quark to the Creo which is the reason I go this round about way)

I think they did calibrate using Dot 2. Should I be using RGB files instead? We print a lot of work for actors- so facial tones are very important. It always seems that the surrounding areas print fine, but when it comes to the face, it's hard to get the color right.

When I went to Konica, they basically printed the color fine- the first time out, without doing any color correction on the press. However, we need to. But, with regular flyers- the colors and printing come out great, its just with the flesh tones we have issues.

thanks for all your help!

[condor99]

Couple of other things.

I do get best results with DOT 2. I tend to use SWOP and Perceputal for the CYMK setting (same I use for Quark Express). Can you help with what the other features mean? Like "black overprint" and "identify black"?

[random]

You should use perceptial and optimised. You should turn off all color management in your application otherwise you would applying two layers of colour management which will give you poor output.

If you need the colour management turned on then turn off the color management on the creo i.e simulation off.

You should avoid converting your images to CMYK.

I think the creo will import jpegs so you should do that and compare the diffference to what you printing.

[Setright]

Pure black toner may be used to save on CMY when the colour result is gray. You will see the letters GCR in this connection, too.

"Identify Black" means the controller/software will look for RGB or CMY combinations where all three are present in equal amounts. These will look gray. If printed with only black toner, this will reduce the price of the print, give a true gray without magenta/cyan tones....and unfortunately also a more rough resolution.

Usually you can choose where to subsitute. Text only, graphics...and so on.


It will make more sense when you start to play around with it.

[BVulgaris]

strange, the random guest mentioned not converting to CMYK. Im guessing thats if you are happy with the RGB simulation?

[redhotrob]

You could have your tech install the latest C6501 gamma sensor assembly. It gives better colour, especially when your print has red. Konica issued a bulletin on this a couple years ago.

[twinax]

Hello,

You are right about the screen selection (DOT1 or DOT2) but I already got this kind of problem.

Solution was to clean the glass on laser unit x4 (only outside glass) nothing was visible on glass, but after cleaning the result was uncredible, Customer said that he never got a print quality so perfect from this cleaning.

After that it is necessary to readjust the engine grey balance, calibration....

Color management can not react properly if the basic engine is not perfect.

try this,

Twinax

[RRodgers]

I just bought a used C6500 with an Creo ic-304 RIP (actually an Ikon 650 powerpro). I am having problems with skin tones, images are becoming a little over exposed, and with the reds, we see some fine lines.

Does anyone have any tips for achieving nice flesh tones?
Any specific Proper settings on the RIP?
Also, Konica came out to calibrate , but did the off the glass calibration, does it make a big difference from using the Densitometer?

I find that DOT 2 Screening gives the best results. I think I have all the patches and update to date firmware.

I tried out the C6501 and found the skin tones great, but decided on saving some money and getting the C6500. Is there a big difference between the two?
Should I be sending files in CYMK or RGB, does it make a difference?

Any help would be great- thanks!

I forget what they use with the Creo's to calibrate. It's been years since I did it in class and we never sold one with a Creo. I always used a Fiery.

You'll need to calibrate that puppy, and often. I take it that you are not a tech, you'll need one... a good one. You are going to have to do the printer gamma adjustments to "grey out" the machine and then calibrate the Rip.

GL