DF-704 Colour Discrepancy

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Slammers
    Technician

    50+ Posts
    • Feb 2019
    • 54

    DF-704 Colour Discrepancy

    I have an Olivetti MF454 (Re-badged Konica Bizhub C458) with a DF-704 dual headed scanner. Had a call come in from a customer concerning scan quality on double sided documents: The back side is always faded/washed out compared to the front side.

    Steps taken:
    Error codes: None
    Frimware updated to G00-W5
    Scanning Light RBG values adjusted through maintenance mode
    Removed CIS unit from ADF and checked for visible signs of damage/dust
    Tried changing file type to rule out compression artefacts
    Contacted technical support - Never seen this issue

    Results:
    After updating firmware there was no change to colour quality of rear side scans.
    After changing file types/dpi there was an improvement to overall scan quality but colours still faded on rear side.
    After removing CIS unit there was no visible damage or dust on the unit, looked brand new.
    After altering RGB values I managed to get the colours to match on both sides - NOTE had to set all values to MAX (+) R G B

    This is where I had left the call. The colours were close enough for the customer and could only notice a difference if under very bright lights and if actively looking for discrepancies.

    However, fast forwards to today I got a call back from the customer saying the colours had drifted out again. Got them to send some samples through and sure enough the rear sided colours were faded out again. RBG values still set at MAX, no more room for adjustment.

    Crunch time: Has anyone else experienced this issue and what was done to resolve it. Should I order a new CIS Scanning unit for the ADF, could it be the DFPU inside the ADF itself or the board that plugs into the main body?

    I have a feeling the LED's on the CIS Scanning section have lost intensity, however I have no spare DF-704s to donate parts/test.

    Thank you for your time.
  • rolls.bo
    Technician
    • Sep 2014
    • 37

    #2
    Re: DF-704 Colour Discrepancy

    Firmware for Function Version 4.2 Version ver.Gxx-U8/V1/W5.

    About Software Switch Settings
    Switch No.: 25

    HEX Assignment: B0 -> Function Version 4.2

    this Software Switch enable version 4.2

    VERY IMPORTANT

    Execute [Service Mode] -> [System 2] -> [CCD Calibration].
    Last edited by rolls.bo; 04-07-2019, 08:44 PM.

    Comment

    • Slammers
      Technician

      50+ Posts
      • Feb 2019
      • 54

      #3
      Re: DF-704 Colour Discrepancy

      Originally posted by rolls.bo
      Firmware for Function Version 4.2 Version ver.Gxx-U8/V1/W5.

      About Software Switch Settings
      Switch No.: 25

      HEX Assignment: B0 -> Function Version 4.2

      this Software Switch enable version 4.2

      VERY IMPORTANT

      Execute [Service Mode] -> [System 2] -> [CCD Calibration].

      Thank you for this, I managed to stumble on this while doing my prep before returning to site. Had to perform the calibration, re-boot, then re tweak the RGB values for the scanner bar after I had changed them at the previous attempt to correct.

      What I found odd was the fact the the colours had drifted so off on the original firmware and loading the W5 made zero effect to the output I was getting. Have added the CCD calibration to my maintenance checklist on the double head units for future reference. Thank you again for the info.

      Comment

      Working...