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davidj7
02-12-2013, 02:29 PM
Hi
I have attached 2 images one is 'image gradation -print' its perfectly okay and the other is 'image gradation -copy' which is having image quality issues in all colours.
I have done basic cleaning of the glass, mirrors but no change . I havent touched the CCD .
I am trying my hands on KM for the first time .

Its basically a copy problem so any ideas on where I should start .

Thanks
David

blazebusiness
02-12-2013, 04:22 PM
Hi
I have attached 2 images one is 'image gradation -print' its perfectly okay and the other is 'image gradation -copy' which is having image quality issues in all colours.
I have done basic cleaning of the glass, mirrors but no change . I havent touched the CCD .
I am trying my hands on KM for the first time .

Its basically a copy problem so any ideas on where I should start .

Thanks
David

Copy quaity resolution will never compare to print resolution and hence may reveal any inconsistancy with the image units that doesn't show up as much when printing. That being said, you obviously need to start with the optics as the prints look ok. Remove the original glass.Using a cleaning pad dampened withalcohol, wipe the mirrors. Then make more copies to see if there is any improvement. Also, take note as to whether your copying the origional in text mode as opposed to photo as this will also influence the copy quality if you try to copy an item that is more of an image but have the machine set to treat the image as text.

If cleaning the optics doesn't help----How do those image units look? What's the meter count on that machine?

davidj7
02-12-2013, 04:33 PM
Hi blaze
the meter count on the machine is 172,000. The prints are 100% perfects only copy show Image quality defects.If you compare the internal test print of print and copy you will see noticeable quality deterioration in copy .So the laser and drums are okay. I ve cleaned the glass and mirrors.

blazebusiness
02-12-2013, 04:40 PM
Hi blaze
the meter count on the machine is 172,000. The prints are 100% perfects only copy show Image quality defects.If you compare the internal test print of print and copy you will see noticeable quality deterioration in copy .So the laser and drums are okay. I ve cleaned the glass and mirrors.

Understood. Copies will never look as good as prints.The darker parts of the gradiation copy look ok---Only the lighter parts of the origional look a little washed out. Again--copies will never look as good as prints. Are you copying the image in text mode? Also the top and bottom of the image shows some variation in density when I compare them in your example which speaks to me of image units or some cleaning item. Things you can try to help variation:
Clean Charger wires with wire cleaning tool
Clean PH windows using cleaning pad assy

davidj7
02-12-2013, 05:05 PM
hi blaze,
i know copies will never look as good as print but i have much better gradation copies . As you said 80-100% fills are fine , lines appear in 80-50% , less than 50% its hardly visible.You are right on density difference in in board and out board end , the inboard end is lighter.

blaze these prints were made in extended service mode ,gradation adjustment copy/print.

What do you mean by "Clean PH windows using cleaning pad assy". I dont have much experience on KM

blazebusiness
02-12-2013, 05:17 PM
19425
19426

davidj7
02-12-2013, 05:25 PM
Oh yes I have cleaned both , I just wasn't familiar with the terminology.

blazebusiness
02-12-2013, 05:28 PM
Oh yes I have cleaned both , I just wasn't familiar with the terminology.

Then your variation is due to the image units. Just doesn't show up as much in prints yet because images when you print are much stronger. That's my best guess. Hope that helps.

davidj7
02-12-2013, 05:44 PM
OKay I will check that and revert back to you

PeterG
02-13-2013, 04:12 AM
If I am understanding you correctly, those images are the ones when you are doing the gradation.
That is normal. They all do that.

RRodgers
02-13-2013, 04:16 AM
Hi
I have attached 2 images one is 'image gradation -print' its perfectly okay and the other is 'image gradation -copy' which is having image quality issues in all colours.
I have done basic cleaning of the glass, mirrors but no change . I havent touched the CCD .
I am trying my hands on KM for the first time .

Its basically a copy problem so any ideas on where I should start .

Thanks
David

I've learned a LONG TIME AGO (back on the 8020) NEVER EVER, EVER copy these and expect them to look any good.

davidj7
02-13-2013, 05:30 AM
peter, rrodgers@ copy is the internal extended service mode copy and not a copy i have taken from the platen glass.It used to come perfectly like the " gradation-print " till a few weeks back.

EarthKmTech
02-13-2013, 05:37 AM
peter, rrodgers@ copy is the internal extended service mode copy and not a copy i have taken from the platen glass.It used to come perfectly like the " gradation-print " till a few weeks back.

They never look the same as the gradation print even out of the box, period.

What you're seeing is normal and not a fault.

davidj7
02-13-2013, 05:48 AM
i am getting image quality problems in copies with copy being light in the inboard side . the gradation prints i ve attaches started going bad at the same time so for easier comparison i ve attached that.

I have been working on copiers/printers long enough to understand the point all of you are trying to make and i know i cant expect the same quality in copies and prints .I get that ,but when one fine morning i get copy quality issues and one side is lighter than the other and i get small horizontal lines in copy only i know something is wrong . Please understand that I didnt have this problem in copy till few weeks ago.

Gaffers01
02-13-2013, 09:27 AM
Right as previously said by someone else, the prints that you have attached to your original post are normal, every one of these model machines new from the box look like that.

You need to show a copy from the platen so we can have a look at the actual problem that you have not the Graduation sheet.

habik
02-13-2013, 10:26 AM
I would do this:


Pull the transfer belt out and give the front and rear IDC sensor a wipe with microfiber cloth and also the same for optics..just pure ISO propyl alcohol wipe with microfibre cloth and then polish it after with a dry one.

Then in service mode, Image Process Adjustments > Stabiliser > Initialize and Image Stabilization
then
Gradation Adjust > Stabilizer > Copy Mode and Print Mode. For the best results make sure you get to the bear minimum a.e as close to zero on both Dark and Highlights Conversion Values.

Also I would check colour registration adjust.

As much as all above look as standard I do them each and every time I have a complain about copy or print quality. Never the less, do you have the PPLM firmware installed to prolong the life of IU's ? If you do, maybe it is time to change the drums!

Be the best and Best of Luck,

Habik

davidj7
02-19-2013, 01:39 PM
Hi
I traced the problem to magenta Developer assy. Looks like there wasn't enough developer.

Thanks for all your help guys .
David

AjitN
02-20-2013, 03:50 AM
HI
I think gradation pattern for copy is very much OK. It always prints like that compare to gradation for Print Mode.
If you test 100 machines, all machines will give you similar output for gradation copy mode.
I think software is designed that way to judge the image loss in copy mode. Actually gradation test page for copy is not a copy but file print only stored in firmware.
I think you should not worry much as long as copy quality is ok.
Hope this helps.

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