[gentoo-user] Scanner and weird streaking

[gentoo-user] Scanner and weird streaking

[Dale]

Howdy all,

I have a HP scanjet 4570c flatbed scanner.  I bought it used years ago
and most of the time, it works just fine.  On occasion tho, I get
something weird.  When I scan something, it adds some pinkish colored
streaks.  I took a scrap sheet of paper and scanned the back of it. I
used a magic marker on some text that was there, also drew a smiley face
on it as well.  Anyway, the side with print is on the opposite side. 
Basically, it is also seeing the back side of the paper.  I'm not sure
if that could cause this weird streaking but wanted to mention it.

At first, I thought it was something on the glass so I disassembled the
thing and cleaned it as best as I could.  When I put it back together, I
concentrated on the back side of the glass, since I have to disassemble
it to clean it.  I also clean the side the document goes on regularly. 
If it changed, I can't tell it.  Another odd thing, the streaks change
depending on the document.  Sometimes you can barely see it, other times
it is awful.  I've not been able to reason out what makes the difference
tho. 

I've got about the same results using Scanlite, Scanpage and XSane
software.  XSane may be a tiny bit better but it does vary at times.
There's not a lot of settings available.  I tend to use either 100dpi or
300 dpi for resolution thingy. I fiddled around a bit but it doesn't
seem to help.  This is a link to the page I described above.  It's a
little sizey so I didn't want to attach, for those who have email
clients that puke a lot.  lol 

https://freeimage.host/i/HTQLpWb

You may notice that it is a little heavier at the top and gets lighter
as it goes down.  I've checked the glass, I can't find anything that
would cause this.  Is my scanner just going bad?  Am I doing something
wrong with a setting or something?  Any ideas?  Thoughts?

Thanks.

Dale

:-)  :-) 

P. S.  After a couple weeks, my backup finished for that large directory
on the NAS.  I even did a update.  It took a while but it's done.  It
would have been sooner but we had a power failure, or two.  It got
really cold here. 

Re: [gentoo-user] Scanner and weird streaking

[Michael]

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On Friday, 30 December 2022 02:28:32 GMT Dale wrote:
> Howdy all,
> 
> I have a HP scanjet 4570c flatbed scanner.  I bought it used years ago
> and most of the time, it works just fine.  On occasion tho, I get
> something weird.  When I scan something, it adds some pinkish colored
> streaks.  I took a scrap sheet of paper and scanned the back of it. I
> used a magic marker on some text that was there, also drew a smiley face
> on it as well.  Anyway, the side with print is on the opposite side. 
> Basically, it is also seeing the back side of the paper.  I'm not sure
> if that could cause this weird streaking but wanted to mention it.

I've come across the pink hue artefact on an old HP scanner, but can't recall 
the model.  It is not related to the print of the opposite side becoming 
visible, which is caused by a high light exposure setting.  You need to reduce 
the exposure to a level where you can see the primary print clear enough, 
without the back side bleeding through.


> At first, I thought it was something on the glass so I disassembled the
> thing and cleaned it as best as I could.  When I put it back together, I
> concentrated on the back side of the glass, since I have to disassemble
> it to clean it.  I also clean the side the document goes on regularly. 
> If it changed, I can't tell it.  Another odd thing, the streaks change
> depending on the document.  Sometimes you can barely see it, other times
> it is awful.  I've not been able to reason out what makes the difference
> tho. 

Cleaning the glass won't affect the pink hue.  I dismantled the scanner and 
cleaned the glass too, with no improvement.


> I've got about the same results using Scanlite, Scanpage and XSane
> software.  XSane may be a tiny bit better but it does vary at times.
> There's not a lot of settings available.  I tend to use either 100dpi or
> 300 dpi for resolution thingy. I fiddled around a bit but it doesn't
> seem to help.  This is a link to the page I described above.  It's a
> little sizey so I didn't want to attach, for those who have email
> clients that puke a lot.  lol 
> 
> https://freeimage.host/i/HTQLpWb
> 
> You may notice that it is a little heavier at the top and gets lighter
> as it goes down.  I've checked the glass, I can't find anything that
> would cause this.  Is my scanner just going bad?  Am I doing something
> wrong with a setting or something?  Any ideas?  Thoughts?

The pink hue is probably due to the scanner bar going bad.  Some fixes, which 
did not work in my case, are as follows:

1. Reset internal chipset:  Plug it in, switch it on, then pull the power 
lead, followed by the USB.  Wait for a minute or longer to discharge, then 
reconnect, power on and try to see if the problem is fixed.

2. Overheating: More of a problem in the summer.  Use a desk fan while 
operating to see if it makes a difference.

If none of the above work, then the scanner bar needs replacing.  Probably 
time for a new scanner, unless you can find a donor scanner for the scanner 
bar.

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Re: [gentoo-user] Scanner and weird streaking

[Dale]

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Michael wrote:
> On Friday, 30 December 2022 02:28:32 GMT Dale wrote:
>> Howdy all,
>>
>> I have a HP scanjet 4570c flatbed scanner.  I bought it used years ago
>> and most of the time, it works just fine.  On occasion tho, I get
>> something weird.  When I scan something, it adds some pinkish colored
>> streaks.  I took a scrap sheet of paper and scanned the back of it. I
>> used a magic marker on some text that was there, also drew a smiley face
>> on it as well.  Anyway, the side with print is on the opposite side. 
>> Basically, it is also seeing the back side of the paper.  I'm not sure
>> if that could cause this weird streaking but wanted to mention it.
> I've come across the pink hue artefact on an old HP scanner, but can't recall 
> the model.  It is not related to the print of the opposite side becoming 
> visible, which is caused by a high light exposure setting.  You need to reduce 
> the exposure to a level where you can see the primary print clear enough, 
> without the back side bleeding through.
>

I kinda figure that.  It is pretty bright.  I don't recall seeing a
setting for it but I may not have seen it.  I mostly tried different
color settings, resolution and such.  Goes to show tho, it is
sensitive.  ;-) 


>> At first, I thought it was something on the glass so I disassembled the
>> thing and cleaned it as best as I could.  When I put it back together, I
>> concentrated on the back side of the glass, since I have to disassemble
>> it to clean it.  I also clean the side the document goes on regularly. 
>> If it changed, I can't tell it.  Another odd thing, the streaks change
>> depending on the document.  Sometimes you can barely see it, other times
>> it is awful.  I've not been able to reason out what makes the difference
>> tho. 
> Cleaning the glass won't affect the pink hue.  I dismantled the scanner and 
> cleaned the glass too, with no improvement.
>
>
>> I've got about the same results using Scanlite, Scanpage and XSane
>> software.  XSane may be a tiny bit better but it does vary at times.
>> There's not a lot of settings available.  I tend to use either 100dpi or
>> 300 dpi for resolution thingy. I fiddled around a bit but it doesn't
>> seem to help.  This is a link to the page I described above.  It's a
>> little sizey so I didn't want to attach, for those who have email
>> clients that puke a lot.  lol 
>>
>> https://freeimage.host/i/HTQLpWb
>>
>> You may notice that it is a little heavier at the top and gets lighter
>> as it goes down.  I've checked the glass, I can't find anything that
>> would cause this.  Is my scanner just going bad?  Am I doing something
>> wrong with a setting or something?  Any ideas?  Thoughts?
> The pink hue is probably due to the scanner bar going bad.  Some fixes, which 
> did not work in my case, are as follows:
>
> 1. Reset internal chipset:  Plug it in, switch it on, then pull the power 
> lead, followed by the USB.  Wait for a minute or longer to discharge, then 
> reconnect, power on and try to see if the problem is fixed.
>
> 2. Overheating: More of a problem in the summer.  Use a desk fan while 
> operating to see if it makes a difference.
>
> If none of the above work, then the scanner bar needs replacing.  Probably 
> time for a new scanner, unless you can find a donor scanner for the scanner 
> bar.

Well, bummer.  I was afraid it was going bad.  I knew it moved the light
thing back and forth and all but know there is a lot more to it than
that.  If it was a consistent streak, I'd think a bad CCD or whatever
that chip that grabs the image is called nowadays.  This tho, wasn't
looking like that. 

I may disassemble it again and check all the cables. Disconnect and
reconnect everything and hope for a bad or lose connection.  Now let us
pray. 

Given I only use Linux, know of any good and commonly available flatbed
scanner models?  I'm fine with used ones as long as they work.  I like
the one I got since when I'm done, it stands upright in my closet and
takes up very little floor space.  It does a really good job. I've even
scanned in pictures and they looked good, when it wasn't doing the
streak thing. 

Thanks.

Dale

:-)  :-) 


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Re: [gentoo-user] Scanner and weird streaking

[Mark Knecht]

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On Fri, Dec 30, 2022 at 6:42 AM Dale <rdalek1967@gmail.com> wrote:
<SNIP>
> Well, bummer.  I was afraid it was going bad.
<SNIP>
;-)
If it's still moving then it isn't necessarily bad.

Possibly you need a new goal for your old equipment?

https://www.youtube.com/watch?v=9Hfj_SuVm_0

Good luck,
Mark

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Re: [gentoo-user] Scanner and weird streaking

[Wols Lists]

On 30/12/2022 13:42, Dale wrote:
> Given I only use Linux, know of any good and commonly available flatbed
> scanner models?  I'm fine with used ones as long as they work.  I like
> the one I got since when I'm done, it stands upright in my closet and
> takes up very little floor space.  It does a really good job. I've even
> scanned in pictures and they looked good, when it wasn't doing the
> streak thing.

What do you have by way of a printer? Would you be better with an MFP?

Okay, it's not cheap, but I like my HP MFP M477. Cost about £300 for the 
fdn model. Duplex printer, duplex scanner with document feed, cat-5 
(don't think it's wireless).

You can probably get similar cheaper ...

The thing I really like scanner wise is I just set up a Samba share on 
my computer, configure the thing, and then I can just scan from the 
printer front panel and it appears on my computer automagically.

Cheers,
Wol

Re: [gentoo-user] Scanner and weird streaking

[Michael]

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On Friday, 30 December 2022 13:42:04 GMT Dale wrote:
> Michael wrote:
> > On Friday, 30 December 2022 02:28:32 GMT Dale wrote:
> >> Howdy all,
> >> 
> >> I have a HP scanjet 4570c flatbed scanner.  I bought it used years ago
> >> and most of the time, it works just fine.  On occasion tho, I get
> >> something weird.  When I scan something, it adds some pinkish colored
> >> streaks.  I took a scrap sheet of paper and scanned the back of it. I
> >> used a magic marker on some text that was there, also drew a smiley face
> >> on it as well.  Anyway, the side with print is on the opposite side.
> >> Basically, it is also seeing the back side of the paper.  I'm not sure
> >> if that could cause this weird streaking but wanted to mention it.
> > 
> > I've come across the pink hue artefact on an old HP scanner, but can't
> > recall the model.  It is not related to the print of the opposite side
> > becoming visible, which is caused by a high light exposure setting.  You
> > need to reduce the exposure to a level where you can see the primary
> > print clear enough, without the back side bleeding through.
> 
> I kinda figure that.  It is pretty bright.  I don't recall seeing a
> setting for it but I may not have seen it.  I mostly tried different
> color settings, resolution and such.  Goes to show tho, it is
> sensitive.  ;-) 

If the scanner front end doesn't offer an exposure tweak, you could try post-
processing of the scanned image using Gimp, or some other image editing 
software.  Reduce exposure until the reverse side print dissipates, while the 
front remains clear enough.

Alternatively, on a simpler set of controls playing with brightness and 
contrast could get you close enough.


> >> At first, I thought it was something on the glass so I disassembled the
> >> thing and cleaned it as best as I could.  When I put it back together, I
> >> concentrated on the back side of the glass, since I have to disassemble
> >> it to clean it.  I also clean the side the document goes on regularly.
> >> If it changed, I can't tell it.  Another odd thing, the streaks change
> >> depending on the document.  Sometimes you can barely see it, other times
> >> it is awful.  I've not been able to reason out what makes the difference
> >> tho.
> > 
> > Cleaning the glass won't affect the pink hue.  I dismantled the scanner
> > and
> > cleaned the glass too, with no improvement.
> > 
> >> I've got about the same results using Scanlite, Scanpage and XSane
> >> software.  XSane may be a tiny bit better but it does vary at times.
> >> There's not a lot of settings available.  I tend to use either 100dpi or
> >> 300 dpi for resolution thingy. I fiddled around a bit but it doesn't
> >> seem to help.  This is a link to the page I described above.  It's a
> >> little sizey so I didn't want to attach, for those who have email
> >> clients that puke a lot.  lol
> >> 
> >> https://freeimage.host/i/HTQLpWb
> >> 
> >> You may notice that it is a little heavier at the top and gets lighter
> >> as it goes down.  I've checked the glass, I can't find anything that
> >> would cause this.  Is my scanner just going bad?  Am I doing something
> >> wrong with a setting or something?  Any ideas?  Thoughts?
> > 
> > The pink hue is probably due to the scanner bar going bad.  Some fixes,
> > which did not work in my case, are as follows:
> > 
> > 1. Reset internal chipset:  Plug it in, switch it on, then pull the power
> > lead, followed by the USB.  Wait for a minute or longer to discharge, then
> > reconnect, power on and try to see if the problem is fixed.
> > 
> > 2. Overheating: More of a problem in the summer.  Use a desk fan while
> > operating to see if it makes a difference.
> > 
> > If none of the above work, then the scanner bar needs replacing.  Probably
> > time for a new scanner, unless you can find a donor scanner for the
> > scanner
> > bar.
> 
> Well, bummer.  I was afraid it was going bad.  I knew it moved the light
> thing back and forth and all but know there is a lot more to it than
> that.  If it was a consistent streak, I'd think a bad CCD or whatever
> that chip that grabs the image is called nowadays.  This tho, wasn't
> looking like that. 
> 
> I may disassemble it again and check all the cables. Disconnect and
> reconnect everything and hope for a bad or lose connection.  Now let us
> pray. 

The pink hue is visible signal noise captured in the image.  This may be 
internal, the scanner sensor is drifting outside its spec, or it could be some 
external source.  Do you always use the scanner in the same position on your 
desk, or does it give different results depending on location?  Strong 
electromagnetic interference may exacerbate the problem.


> Given I only use Linux, know of any good and commonly available flatbed
> scanner models?  I'm fine with used ones as long as they work.  I like
> the one I got since when I'm done, it stands upright in my closet and
> takes up very little floor space.  It does a really good job. I've even
> scanned in pictures and they looked good, when it wasn't doing the
> streak thing. 
> 
> Thanks.
> 
> Dale
> 
> :-)  :-) 

I only have a very old 23 year old CanoScan N650U flat bed scanner with just 
one button on it!  It has worked faithfully for years with no problems, but my 
scanning needs are simple.

In case you are looking for used items on ebay, beware what you're buying may 
be in a worse state than what you are trying to replace.  Business clearance 
items can prove to be a bargain, but without testing in your environment you 
can't be sure.

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[gentoo-user] Scanner and weird streaking

[Urs Schütz]

Any chance you need to shield the scanner from light sources outside the scan head?
Throw a dark jacket over it for testing.

Re: [gentoo-user] Scanner and weird streaking

[Mark Knecht]

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On Fri, Dec 30, 2022 at 1:12 PM Urs Schütz <u.schutz@bluewin.ch> wrote:
>
> Any chance you need to shield the scanner from light sources outside the
scan head?
> Throw a dark jacket over it for testing.

Or if it's that the light is for some reason too bright and the inside of
the lid is reflecting
it then try a piece of black construction paper on the underside of the lid.

- Mark

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