View Full Version : Bizhub pro C500: orange problem.

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02-27-2009, 08:50 AM

i have a used Bizhub pro C500, and CF5001.

Colours on prints of CF5001 are much more intensive, espessially red.

i try to replace drums, developer, recalibrate, search in forums and do all recomendations about "orange problem".

when i install dev units from CF5001 to C500, red is good, but after 200-300 prints it become "as usual" - orange.

then i took a color registration assy from CF5001 and install it to C500 - colours become slightly more intensive, but after recalibration effect is gone.

in scans green arrow is direction of moving of paper in copier.

near the edges, or near the white symvols or rgaphics density of "red" is nearly normal.

Thank you very much!

02-27-2009, 12:00 PM
You perform the gamma sensor calibration (reset for each screen also) after changing the sensor board? Your making your problem worse if you haven't

02-27-2009, 12:16 PM
yes, reset for priner gamma sensor and gamma sensor offset and after that recalibrate.

what can you say about high density at the edges and low density in the middle?

02-28-2009, 02:48 AM
first thing to realize is that although the CF5001/8050 and C500 are just about the same machine , the starter is different and possibly the toner(can't remember).The starter for the C500 is marked "for use in C500 only" so if you are switching dev units between models then you are getting mixing of the starter / toner. One thing to try is turn off spot color matching on the Fiery and see if you get any better reds. We find turning it off gives more vibrate reds. Of course this is after performing the calibration for the machine and the fiery(off the glass calibration of the Fiery sucks so make sure you use a spectrophotometer)

BTW before performing any calibration that requires patches to be read by the scanner, clean the optics and mirrors! Remember that these animals are used mostly as printers and we sometimes forget about the scanner maintance.

03-02-2009, 08:44 AM
red is a mix of yellow and magenta when red turns to orange there is either more or less of 1 of the colours ie more yellow or less magenta still means more yellow. There seems to be a problem with the toners. i suggest throwing the magenta out. be sure to shake the new 1 and replace . then you need to flush the sump so the new toner is available to the dev unit perhaps 50 half tones at 255 will do it. This problem is common with many variations from white spot to washed out copies all being related to toner. then do gamma and calibrate. The reason it was ok wen you replaced your dev unit for couple hundred copies because then the badly performing toner infected your dev unit. The moral is always shake your dev and toner before replacing. This still applys to all toner and dev

03-02-2009, 10:23 AM
so, i think it was gamma sensor.

after 50-100 copys and 2-3 recalibrations colours become really intensive.
all other parts was old, only gamma sensor assembly from another copier (CF5001).

now i may be will install old assembly and look what will happend, if "orange problem" will appears again - so, gamma sensor is bad.

can i replace only gamma sensor plate, not whole assembly?
i plan to find sensor or assembly from used copier.

what is a difference between old and new types of sensors? marking, codes or something like that.

thank you very much!

03-05-2009, 04:30 PM
no, it was HUMIDITY.

next morning orange problem starts again on this gamma sensor.

i get a gygrometer and check - humidity af the air in the room was 11%.

so after it become 35-40% and copier was turned on and did a usual start-up calibration, colours become very good, espessially red.

i check 2-3 times, when humidity was below 20-25%, colours become too lite.

now copier works with old gamma sensor and air humidifier in room :-)

03-05-2009, 09:29 PM
You can check humidity also in the 4-7 mode

03-05-2009, 09:37 PM
about 4-7 mode - where can i get manual for this mode?

i have only for 3-6 and 2-5

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