C65hc - density to low

[atelje]

With C65hc we reach only those D-max values:
C 0.88 / M 1.19 / 0.89 Y / K 1.94

My opinion, all values except black far too low. This proves also target D-Max of profile-KM Fiery C65hc Coated V1F:
C 1.15 / M 1.32 / 0.94 Y / K 1.80

Now I've tried using different procedures to improve density (e.g. Utility: Toner Quantity / Exposure Adjustment, Service: Toner Density Fine Adjustment) now it's like this:
C 0.91 / M 1.24 / 0.91 Y / K 1.69

So Black is revised downwards, but CMY succeeds almost no jump upward.

How can I achieve higher CMY values?

For any advice I am very grateful!

------------------------
KM bizhub Pro C65hc
Fiery Server-C65hc (65C-KM V 3.0a)
Fiery System: 9, Installed Patches: 1-WO939, 1-1484WD
Output Profile: Fiery C65hc-KM Coated v1F

[atelje]

any suggestion?

[kalindd]

Re: C65hc - density to low

Whats the print count, drum, developer counters?
With what tool you are measuring those values, i-1?
provide me some more info.
Are you a tech?

[atelje]

Re: C65hc - density too low (How to increase Dmax?)

Kalindd, thank you for response.

I'm no tech but only "advanced" user.
Of course adjustments in the Service Field do our KM-tech.

More few clarifications:

- I noted that Dmax of our HC-Cyan from the beginning is too low. At the installation from a year and half was around:
C 0.95 / M 1.40 / Y 0.95 / K 1.9.

- In recent months we have noticed that Dmax sliding down. Now, even equally MY, approximately:
C 0.85 / M 1.15 / 0.85 Y / K 1.94. Black continue to fine or even too high.

- In recent days we are made a lot with my tech about this problem.
We raised the value within Service Fields: Develop AC Bias fine adj. and Toner density fine adj., finally conduct Auto gamma adj. and all possible settings with Utillities: Toner quantity / Exposure adj., Dens eveness adj., Frontback density, Image quality stab., Gamma offset adj....) the best result about:
C 0.95 / M 1.30 / Y 0.97 / K 1.9.
Dmax of MYK is fine, but C is still not right.
And to clarify: this setting is only temporary, because the impression is now worse: increased noise and fine-line interferences. Line 1 or 2 is even worse than the Dot 1 or 2.

With what tool you are measuring those values, i-1?

This is a good question. Almost could start another thread.

To avoid the influence of color management (Fiery etc.) we print No. 53 test pattern.

The measurements were performed with ES-1000 (UV-cut) with PM Measure Tool, Paper white, standard ANSI-T.
Finally, the same measurements also confirmed the Fiery Color Wise Calibrator with ES-1000 (UV-cut), DTP-41 (UV-cut) and DTP-41.
In the measurements no significant differences.

For comparison, we also have the test pattern print from other little used C65hc, the same model and year, the same measurement conditions.
We measured the following values:
C 1.05 / M 1.36 / Y 0.98 / K 1.7 (interesting a bit too low C).

Whats the print count, drum, developer counters?
provide me some more info.

State of parts?
Seems good, otherwise change as recommended in service periodic check list.
Counter and Life cycle? Details in attachment.

[kalindd]

Re: C65hc - density too low (How to increase Dmax?)

Counter looks ok.
What is the humidity in you print shop? If it is low this can happen.
Is the low density noticeable by naked eye? If yes, try making "hard stop" and check how your image looks on transfer belt.
Have you cleaned color reg assembly? There is a sensor located there that measure the density on belt and it may send a wrong data.

[atelje]

Is the low density noticeable by naked eye? If yes, try making "hard stop" and check how your image looks on transfer belt.
Have you cleaned color reg assembly? There is a sensor located there that measure the density on belt and it may send a wrong data.

tomorrow we will carry with technicians,
then I report