Calibrated State of Machine

[lversant80]

Hi

Machine Xerox Versant 80 - CWS: 5

I'm hoping someone can clarify an issue of calibrating.

Usually to calibrate (especially on jobs printed before so we know what the colour and quality should be and the stock used) we use custom profiles and fiery default profiles - and when needed usually calibrate job to these - using the paper that the job will be run on etc.

Sometimes we do not always get close to the colour as before.

However a tech guy came in and said that we should be performing a "general" calibration so the whole fiery/machine stays calibrated to a certain degree of accuracy - using the Fiery Default profile - which i think is around 90gsm Uncoated?

I understand this but how would it be done? - simply via the Menu - Server - Calibrate - and follow the instructions (THIS SEEMS TO BE THE SAME BOX THAT APPEARS WHEN i PERFORM A NORMAL CALIBRATION FOR MY PROFILES BEING USED?)

OR is there another route I should be taking?

and should we be using the same stock/weight/finish each time we perform a general calibration?


p.s. if i do a general calibration will other calibrations I do after this over ride it anyway?

Many thanks if someone could clear this up for me!

[adam1991]

Your service guy is wrong.

Can you clarify "we use custom profiles and fiery default profiles"?

[lversant80]

The Fiery Default output profiles and Custom Output profiles that we have generated by using the Colour Profiling Suite.

We calibrate the machine and paper to one of these profiles depending on the job we are running. Sometimes a few different jobs all use the default profile and then we just calibrate the paper type we are using.

Is that what you meant??

.....

So to Calibrate is what we are doing for each job correct? and do we need to perform a general calibration etc?

We have quite a few profiles - surely we cannot calibrate for each of these everyday like its recommended to do it would use so much paper etc.

[SeanRyder]

We are running a Ricoh 751 with fiery. I was told that on the machine itself you do a daily "color registration and auto color calibration", found on the machines maintenance menu. This is to keep the machine at a known calibrated state. Then calibrate the needed profile using Fiery Command Workstation. We've created many custom profiles for the stocks we use most using Fiery Color Profiler Suite Which links to your paper catalog. As far as the Fiery "built in " profiles, plain, coated matte, coated glossy, these are fine for general use but won't be consistent if you use more than one brand of coated paper for instance unless you calibrate every time you switch brands. The Key is to do the daily general machine calibration that way you're not constantly changing the stocks calibration as the machine settings degrade over time due to environmental changes etc.

[adam1991]

The Fiery Default output profiles and Custom Output profiles that we have generated by using the Colour Profiling Suite.

We calibrate the machine and paper to one of these profiles depending on the job we are running. Sometimes a few different jobs all use the default profile and then we just calibrate the paper type we are using.

Is that what you meant??

.....

So to Calibrate is what we are doing for each job correct? and do we need to perform a general calibration etc?

We have quite a few profiles - surely we cannot calibrate for each of these everyday like its recommended to do it would use so much paper etc.

That's what I meant, and you're mostly doing OK with your workflow.

Your service guy is wrong.

That being said: if you're going to use a factory default output profile, I'd almost rather you stick with using one single stock to calibrate for that profile.

That being said, if you're using that factory default profile but are calibrating for individual stocks, you should still get consistent results on those stocks after calibrating for them.

(What you cannot do is mix and match the stocks you calibrate on vs the stocks you run on.)

The calibration, while not the ideal mechanism, should bring you back to a consistent level of color performance on that stock. You're saying it does not. Does it bring the first sheet back to a consistent level? Are you comparing first sheet to first sheet in a run, or are you comparing first sheet in the new run to a middle or late sheet from the previous run?

My first thought is, the "results" you're seeing--inconsistent color performance--come from the machine not holding ink densities well across a run. The calibration process may "fix" color for the first few sheets, but if the machine is varying in ink density and color throughout a run, you'll see that on your output.

[lversant80]

Thanks Adam1991 & Sean - very helpful info you guys have shared!

Then calibrate the needed profile using Fiery Command Workstation. We've created many custom profiles for the stocks we use most using Fiery Color Profiler Suite Which links to your paper catalog. As far as the Fiery "built in " profiles, plain, coated matte, coated glossy, these are fine for general use but won't be consistent if you use more than one brand of coated paper for instance unless you calibrate every time you switch brands. The Key is to do the daily general machine calibration that way you're not constantly changing the stocks calibration as the machine settings degrade over time due to environmental changes etc.

This is what I mean - Do I need to perform a general calibration of this machine?

And yes I Calibrate when needed every time a switch over of different brands of paper.

The calibration, while not the ideal mechanism, should bring you back to a consistent level of color performance on that stock. You're saying it does not. Does it bring the first sheet back to a consistent level?

So what would be the ideal mechanism for calibration? Would it be to make a custom profile for each stock of paper - going by the Fiery Default profiles/start from scratch profiles I wish to use?

We are comparing the first sheet to a previous run - however our environmental conditions are not the best! Its only a few jobs the colour looks vastly different and it doesn't take much altering to get it back to how it should look. - This has mostly been on Substitute Colour groups.

But Like I asked before which is really what I'm trying to understand if needed, is do I need to be perform a general calibration of the machine (daily)?

many thanks

[adam1991]

Do you need to perform a "general calibration" on the Fiery before you do any other calibrations? No.

Do you need to perform any available machine-specific, non-Fiery functions to "calibrate" or linearize the machine to its own specs (max density, inboard/outboard evenness) before doing Fiery calibration? Yes.

Some people call that machine-specific routine "calibration". That's fine. Just understand where you're calibrating.

You want the engine to present its best and most consistent face to the outside world first, before asking the Fiery to profile or calibrate.

[lversant80]

Do you need to perform a "general calibration" on the Fiery before you do any other calibrations? No.

Do you need to perform any available machine-specific, non-Fiery functions to "calibrate" or linearize the machine to its own specs (max density, inboard/outboard evenness) before doing Fiery calibration? Yes.

Some people call that machine-specific routine "calibration". That's fine. Just understand where you're calibrating.

You want the engine to present its best and most consistent face to the outside world first, before asking the Fiery to profile or calibrate.

Ok - Got it! Thanks a lot for going through this with me- really appreciate the advice and time!

[StarDigital]

In addition. If you are allowed, make sure the density sensors are clean of waste toner. If you calibrate your machine on dirty senors you won't get consistant results.

Every monday i clean my sensors of the waste built up on them over the previous week, then run machine 'linerization', i think its called (where the machine calibrates its dot pattern density and postions across feed direction along the transfer belt, i have a xerox 1000i that i can get to do this), and then run a printoff calibration using the same stock of paper i started the profile with. I use 80# gloss text as it provides the best coverage and results. (this calibration profile is the default caibration for all my paper profiles, this is my choice, so that with one calibration all my stocks are ready to run). Then each day all i need to do is run the 'linearization' in the morning when waking it up and at around noon, when the temprature and humidity levels have changed. This provides the most efficient accuracy for my needs.

If i change a part dealing with image transfer to the paper then i need to redo all of these steps and run other algorithms to get the density and dot patterns adjusted properly. Fortuanately, that doesn't happen often.

[lversant80]

Hi ---- It may or not be different on your 1000i to the versant? - in regards to being able to clean the density sensors?? I can do the drum "windows" with the wand and then its a fuser clean process. How are you cleaning the density sensors - I'm not sure its something I'd wanna touch if its in the machine casing itself....

I can perform a Density Uniformity Adjustment which I carry out if I feel the calibration and colour is ok but one area isn't quite there.

So in all I guess just carry on with my routine with some adjustments as mentioned above in this thread - obviously you hear different methods/info from different people so I guess you have to go by your own experiences etc.