proof to press sheet

[ripit]

I have a couple of questions about what people are doing for proofing in a color managed enviroment, but first a brief history of how we got to today

1. ran linear plates
2. press ran to density to determine dot gain
3. create plate curve-replate
4. press ran to density and we have good gray balance
5. Create profile from press sheet
6. create profile from proof (Fuji Final Proof)
7. we have a good visual match

Fast forward a month and questions are coming up.
My pressroom foreman is complaining that the proof and press sheet are not dot for dot

my question is this, how many printers are providing a dot for dot proof to the pressroom and how can i create a dot for dot proof? Currently I have an artwork systems nexus rip that is sending 8 bit tiff files to the final proof and the final proof rips and screens the proof.

The file and plate contain a Red & Green color that have the following colors
Red Green
35c 67c
100m 29m
57c 91y
23k 11k

But my proof does not have the black in these areas, and we still have a close visual match on press. Is this right?

Sorry about the long post

[David]

ok, just a couple of questions.

8 bit tiff files to the final proof

do you really mean 1 bit tifs?

how many printers are providing a dot for dot proof to the pressroom

are you meaning a screened proof (with say, 150 line screen, as opposed to an inkjet proof which has no screening)?

[clod]

I believe the Final proof has the abillity to proof the same files as the plate yes? Though I understand you have created profiles of both press and proofer, so I assume you're doing a conversion at the proofing stage? That there is no black in those colors, I can't say if this is right or wrong, but what were the black generation characteristic you defined for the proofer profile? Dot for Dot proofing isn't necessary for good proofs, but what you descibe seems strange.

[ripit]

Originally Posted by david_maberry

ok, just a couple of questions.

do you really mean 1 bit tifs?

are you meaning a screened proof (with say, 150 line screen, as opposed to an inkjet proof which has no screening)?

Sorry, yes we are sending unscreened 1 bit tifs
Yes we are screening the proof via the final proof rip. Proof has a round dot

[ripit]

Originally Posted by clod

I believe the Final proof has the abillity to proof the same files as the plate yes? Though I understand you have created profiles of both press and proofer, so I assume you're doing a conversion at the proofing stage? That there is no black in those colors, I can't say if this is right or wrong, but what were the black generation characteristic you defined for the proofer profile? Dot for Dot proofing isn't necessary for good proofs, but what you descibe seems strange.

Yes I can send send the same files to to final proof as well as the platesetter. We currently send unscreened 1 bit tif files to the final proof and 1 bit screened file to the platesetter.
We are doing a conversion at the proofing stage. We used medium black generation when making the profile.
I know that dot proofing is not necessary for a good proof but tell that to the old school foreman that runs the pressroom. He needs a dot although he can not tell me why

[clod]

We'll, sounds like you know what your doing, particularly if your getting a good match. Lack of black in those colors seems odd, but if it matches, may not be indictive of a problem. You could always tell the press foreman that your proofer is completely out of black halftone dots...maybe he has some you could borrow? Barring that, you could give him a Dot for Dot proof to compare to your color managed proof...see which one he likes better and can match easier.

[LoganBlade]

I can say this oly because i do both I work prepress and supervise the pressroom floor and have experience in both.

tell the preforman if he can explain to you why he needs what he needs you will gladly help him but if he can't tell color any more becasue his eyes have gone the way of a yellow cst on everthing he looks at tell him every thing is fine.

You at least have an answer that explains the how and why they look alike you did your job now he needs to do his.

unless you printing artwork everything is pleaseing to the eye

sometime both area are full of them selves

good luck

[detric_1]

In my opinion, you generally CAN'T supply a dot for dot proof to the pressroom due to differences in the materials. Your fuji material is not a perfect color match for your pressroom inks. The profile is going to have to accomodate for that. So if your pressrooms yellow is warm, but clean in your fuji material, the profile is going to introduce some magenta to warm it up (just one example). This is how some other colors get introduced to a proof that don't show up on plates. Also, your devicelink is going to manufacture mechanical dot gain into the proof which is an aproximation of what they're gonna see on press.

The reason why he wants one is that's an old pressroom process. If I got the same size dot on my proof and on my press sheet, it must be right.

I'll tell ya, it's gonna be critically important to get him on board with what you're doing in profiling because he's the second part of the color management loop, and if he's not good at it and understand it, you can go south in a heartbeat.

Just my 2 cents.

Dave

[colorblind]

We currently send unscreened 1 bit tif files to the final proof and 1 bit screened file to the platesetter.

You probably mean unscreened 8 bit tiffs to the final proof. 1 bit means it can only be solid black or solid white and 8 bit means 256 shades per color.

[colorblind]

In my opinion, you generally CAN'T supply a dot for dot proof to the pressroom due to differences in the materials.

In some 1 bit proofing color rips (such as Compose Starproof) you start by defining your cyan, magenta, yellow and black hues to achieve good offset ink match. Then you can introduce a color base to match for different stocks. You also have control of overprint hues (Y and M in red, C and Y in green, M and C in blue and individual control of all 3 primaries in C+M+Y overprints. The result is very close to a press sheet and you can predict subject moirés.