Question Brother 2750DW Blotchy Printing of Scanned PDFs

MikeA01730

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Nov 23, 2014
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Hi,

I have a Brother 2750DW MFC bought on 2/2018 that's worked fine until now, but it just started printing blotchy scanned PDF pages. Copying, printing of non-scanned PDFs, and printing of other file types work fine. Some PDFs were scanned by the device, some by other devices. This same problem happens printing from both Foxit and Adobe Acrobat. The PDFs previously printed correctly on this device and still do on a newer 2750DW on a different PC.

Two 45 min. chat sessions with Brother support didn't help. We verified that the cartridge is the legit Brother product, tried all the software stuff they suggested, and cleaned the drum. Then they told me they can't proceed unless I first consult with Adobe support, which doesn't seem to be available for the free Adobe reader. That's bogus anyway because this happens with both Foxit and Adobe readers and the PDFs print fine on a different PC with a different 2750DW and the same PDF readers.

Any ideas on how to fix this?

Thanks,
Mike
 

MikeA01730

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Nov 23, 2014
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Printing a blank page from Word looks fine. Printing that blank page to a PDF and printing the PDF works fine.

Not only that but it seems that only PDFs generated by scans malfunction. Other PDFs (e.g. mutual fund statement, warranty, assembly instructions, data sheets, recycling guides) all work perfectly. PDFs printed from Web pages, Excel documents, or Word documents are fine. But every PDF generated by a scan, whether generated by this MFC, or Cannon and Epson MFCs I've owned previously, are all similarly blotchy to some degree. I never had this problem printing scanned PDFs before a week ago on this MFC or other MFCs I've owned previously. Weird, no?
 

MikeA01730

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Nov 23, 2014
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I'm thinking that the scanner captures white areas on the paper as very light variations of gray. Printed correctly these very light grey areas are printed as white or almost white. However for some reason my MFC has decided to print very light gray as a darker gray that creates the blotches.

I found the print density setting and tried various values. It was set to 0 (the default) on a range of -6 to +6. When I set it to -6 it reduces the problem but doesn't make it go away. Still not good enough for prime time.

Also the toner cartridge ran out so I replaced it. That made the problem a little worse.
 

ex_bubblehead

Champion
Moderator
Rescan the originals using Black/White only. Unless, of course, there is color or grey scale that must be preserved. Just reduce the exposure until the anomalous grays no longer appear (usually only 1 or 2 clicks lighter do the trick). It's also quite likely that the optics on the scanner in question need cleaning.
 

MikeA01730

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Nov 23, 2014
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Rescanning is not really helpful. I have years of scanned document PDFs that I occasionally need to print. I don't have the time to rescan each time I want to print a document. I'd rather replace the MFC if it I can't make it work.
 

MikeA01730

Honorable
Nov 23, 2014
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Installed Adobe just to test for this problem so it's brand new.
My wife rarely prints scanned PDFs and has offered to switch with me. I think I'll accept her offer.
 

hang-the-9

Titan
Moderator
Printing a blank page from Word looks fine. Printing that blank page to a PDF and printing the PDF works fine.

Not only that but it seems that only PDFs generated by scans malfunction. Other PDFs (e.g. mutual fund statement, warranty, assembly instructions, data sheets, recycling guides) all work perfectly. PDFs printed from Web pages, Excel documents, or Word documents are fine. But every PDF generated by a scan, whether generated by this MFC, or Cannon and Epson MFCs I've owned previously, are all similarly blotchy to some degree. I never had this problem printing scanned PDFs before a week ago on this MFC or other MFCs I've owned previously. Weird, no?
This is probably because you are scanning using image not document with black and white, and are capturing the color of the paper. Since it's not white the printer prints it out as shaded.

Scan the file again, and set it to document black / white mode and lower the quality settings a bit, it's probably set to some high quality color scan.
 

MikeA01730

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Nov 23, 2014
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My wife hardly ever prints scanned documents so the current arrangement is not a problem. I'm tired of spending time fooling with this so I'll let it be for now.

Thanks for the help trying to fix this. I appreciate the time and effort.

Regards,
Mike
 

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