more yellow in 6500

[levino]

Hai All,
in my two bh 6500 the yellow color is more,if i am printing a photograph in the face the yellow tone is more,both are run only 30000 prints

any solution
thanks in advance

[HelpdeskGuy]

A bit more info would help but has the m/c been calibrated using a densitometer through fiery colorpro tools ?.
You can also create custom color profiles for hard to match colors. Try a different color profile ie: efi swop coated or euroscale
If that doesn't work check the toner percentage in your yellow IU it may be over toned.
The fact that it is both m/cs seems to point to color profiling but you never know.
Does the problem occur on all files printed or just the one you were testing?

[levino]

thanks helpdesk,
i am calibrating using the kotak color patches only,the yellow problem is noticible in the file like photos or with greenish like trees.overtoning is not in the deleloper.we can idenify the problem in the face tones.
once again thanks

[Si@danwood]

Asuming that all the regular copy quality adjustments have been correctly performed on the engine ,The 1st thing you MUST do is calibrate the machine/Fiery using a digital spectrometer (ES1000/Eye1) without this tool/procedure you could be fighting with this problem for weeks!!! There are other things you could try but i would be reluctant to go down that route untill the unit has been calibrated using the above mentioned tool...Si

[levino]

Thanks Si,
i am servicing 2 6501 and one 6500,none of the customer got es1000 because of the investment.

i will try to arrange from some other places and update you

[Si@danwood]

Thanks Si,
i am servicing 2 6501 and one 6500,none of the customer got es1000 because of the investment.

i will try to arrange from some other places and update you

Fyi i have heard of these Eye1/ES1000 's available on Ebay for around 500GBP .It is upto yourself/Company whether to invest in one of these and charge the customer each time you have to calibrate, to cure their image qaulity issues. A standard rate for this in the uk would be around 150 GBP per machine/per calibration so you would only need to do each machine twice to recuop your outlay/labour time...Just food for thought...Si

[Stirton.M]

Thanks Si,
i am servicing 2 6501 and one 6500,none of the customer got es1000 because of the investment.

i will try to arrange from some other places and update you

If you want to know if your print engine itself or the Fiery are at fault, you can regenerate a pantone colour in tech rep.

In test pattern area, select pattern 53, and in the CMYK areas, enter the values of a colour you should get on a pantone chart. You may have to do a bit of math to change the percentage to fit into the 255 density range for each colour. For example, if you have 63% yellow as a value in one of your pantones, multiply 255 x 0.63 and that will be the value you enter for yellow. When you do a test using those values, you should get a colour very close to what the pantone chart indicates, provided your machine has had all the proper adjustments and PM related items dealt with properly. This will help you determine if you have a localized issue before you look at the Fiery.

I agree with Si@danwood about the need for a calibrator. Though doing the colourcal strip off the glass will work, it will not give you the best results. At least, not if the machine is to be used in a print shop. Many of my clients use our machine for proofs, which are used for the press guys. The press guys use the same values I described above to create the colours and if there is a difference, they will notice it. Often this is not acceptable.

As for working without a calibrator, you can still create and save and use colour profiles to compensate for colour imbalance. It is not ideal, but does in a pinch. Most of my clients, I show them how to use this, in spite of them having an ES1000. The reason being, they printed something 6 months ago, and they try to reprint it today, but the colour doesn't quite match what they printed 6 months ago. I have no idea what the state the machine may have been in 6 months ago...(ie) the drum age, developer age, charge wires, transfer belt and...you get the idea. Things can drastically change even with weather from one day to the next. So knowing how to manipulate the colour output profiles in the Fiery and use them for specific jobs is very important, and can save you a whack load of time trying to "FIX" the machine to get it to give you what it did 6 months ago.

If you are unsure how to do this, let us know.

[buster68]

I have had several C6500 with the same problem. If you're reds are coming out orange (too much yellow) then its a good indication that the color registration assembly needs to be replaced. There are bulletins on the KonicaMinolta tech site that give the part numbers of the modified and up to date assembly. After you replace the assembly, reset all of your printer gamma values and readjust all gamma processes.

[dljorg]

Color Registration Assembly Diagnosis

Agree with all about the calibration thing - has to happen.

If the Color Reg sensor is a fault the easiest diagnosis is to run test pattern 62 from service mode. Make 8 copies on 8 1/2 x 11 paper. What comes out is a gradation pattern in each of CMYK and then two color combos to make RGB and finally process black. If the Color Registration sensor is bad (actually it is the max density sensor in the assembly) the two darkest bands in the pattern 62 gradation will be the same density. Of course you can't see yellow but you can deduce what it is doing from R and G.

Color registration sensors come in a number of types but easy to identify. If you have one with a pink stickon spot on it this one has been a problem as described with TP 62 above. Next newest type has a large letter M rubber stamped on the sensor (these have been pretty good) and the very latest has a letter N in rubber stamp.

Best Regards from the snows of Connecticut.

[RRodgers]

One thing to note doing cal's off the glass, be SURE to clean the optics. Dirty optics will throw it off some. What I find is usually you won't see the 2% fill. If they are really dirty you probably won't see the 5% fill either.

[ni311]

I believe everyone agree that ES1000 or DTP32/34 is better to use compared with the scanner because using it is more accurate. You really cannot service these machine without a tool to calibrate it.

[kan]

Lets not forgot about the stock used to calibrate, expecially if this calibration is applied to all stocks of paper.
The sensor on spectrometer is reading the reflection on the stock.

[ni311]

Indeed, for the best results, you need to calibrate the machine for every stock of paper that you're using.