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Author Topic: Why Does My Scanner Add Bits To my Scans (Of Photos)?  (Read 9313 times)

Offline neilep

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I have undertaken a mammoth project !....after coming across some old faded photos I have decided to scan each and every photograph that I have (non-digital of course..DUH !!).....it's gonna take a long time but will be worth it.

Thing is...my scanner keeps introducing bits and stuff to each photo...it's more evident in dark patches as shown here:



Now, I can ' fix' them with no problem but it takes a while and the original photos do NOT have these bits and the scanner glass is pristine !...so...is it a faulty scanner  ? or has my scanner been possessed by a photo corruption poltergeist ???


whajafink



« Last Edit: 04/02/2010 12:18:48 by neilep »


 

Offline Geezer

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #1 on: 03/02/2010 20:11:37 »
Quel Bummer!  I think there may actually be very small blemishes and oil (finger prints) on the surface of the photo that the scanner is amplifying.

I think you should be able to adjust the contrast ratio (sensitivity?) of the scanner to reduce the effect, but that might be baloney 'cos I have not messed with my scanner for ages.

BTW - this reminds me I had planned to scan all my photos too. I started a few years ago, but gave up after a few nights. It takes ages. Mind you, I did eliminate several boxes of paper files by scanning them - my scanner has a feeder. I got to the point where I realized it was not worth worrying about redundant files, duplicates etc. Storage is so cheap so why bother? I simply scanned everything in sight.

I almost destroyed my shredder getting rid of the originals. I mounted the head of the shredder on top of a huge trash can so I didn't have to keep stopping to empty the thing. The mechanism overheated because it was running continuously for 15 - 30 minutes at a shot  ;D

 

Offline neilep

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #2 on: 03/02/2010 21:50:29 »
Thanks Mr Geezer,

yes, it is a tres arsey !

Although a few photos do indeed have the odd fingerprint upon them....in cases where there are no prints at all, the bits and pieces still happen.

I am determined to scan the whole lot...I've already done nearly 700 and this is with no auto feeder at all...I scan about three or four at a time and then separate them in a photo/paint program.

Having them on the PC and backed up on hard disk and online means we'll all see them a lot often.



 

Offline yor_on

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #3 on: 03/02/2010 22:04:11 »
Ahh. :)

Then you can start on your old vinyls too Neil.

Just scan them in and save them for prosperity. I just love this idea. I think it will be like cloning, just better..

Wonder if I could he get a EU grant for this?
As a project, like "scan your environment, save the world"?

Or "Feeling blue today, try our scanner"

Ah, that last one I'm not that sure on of course, but you can control the colors too, can't you?
 

Offline neilep

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #4 on: 03/02/2010 22:12:48 »
There are in fact record players like this one:




............that connect via USB to your PC so that you can store all your old vinyl and convert to MP3...which is nice ! :)

 

Offline BenV

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #5 on: 03/02/2010 22:34:28 »
I still listen to my vinyl!

It looks like there is some dirt on the scanner glass - perhaps on the inside?

Can you scan at a higher resolution?  That may help to avoid digital errors.  Are they matt or gloss finish photos? 

You may find it's actually quicker and easier to set up some lights and a tripod and photograph your pictures - may well be quicker than a scanner.
 

Offline RD

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #6 on: 03/02/2010 22:48:46 »
If the dust pattern on the images is consistent on different photos, (try superimposing them),
 then the dust is on the scanner glass, (perhaps the underside).

BTW a thumbnail of the full image is included in the dusty enlarged section you posted ...


                                                                                                                   [ pixelated by me ]
« Last Edit: 03/02/2010 22:56:35 by RD »
 

Offline neilep

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #7 on: 03/02/2010 22:53:53 »
I still listen to my vinyl!

It looks like there is some dirt on the scanner glass - perhaps on the inside?

Can you scan at a higher resolution?  That may help to avoid digital errors.  Are they matt or gloss finish photos? 

You may find it's actually quicker and easier to set up some lights and a tripod and photograph your pictures - may well be quicker than a scanner.


Thanks Ben,

i still love listening to vinyl too.

I will try scanning at a higher resolution and see what happens. They are a mixture of matt and gloss and I will take note to see if it happens to more than one finish than the other.

I like your idea of photographing the photos but I have is a ten year old sony digital compact....perhaps *puppy dog eyes mode* if the naked scientists were to give lend me a digital SLR then that would be nice !!  ;)
 

Offline neilep

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #8 on: 03/02/2010 22:59:29 »
If the dust pattern on the images is consistent on different photos, (try superimposing them),
 then the dust is on the scanner glass, (perhaps the underside).

BTW a thumbnail of the full image is included in the dusty enlarged section you posted ...


                                                                                                                   [ pixelated by me ]



?????

Please explain further how the full image appeared ??...it can not be so..I uploaded just a cut out !!!..*puzzled*...thanks for pixelating !


Unfortunately the dust pattern is not consistent......
« Last Edit: 03/02/2010 23:01:04 by neilep »
 

Offline RD

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #9 on: 03/02/2010 23:11:24 »
Please explain further how the full image appeared ??...it can not be so..I uploaded just a cut out !!!..*puzzled*...thanks for pixelating !

Unfortunately the dust pattern is not consistent......


If the dust pattern is not consistent then it is caused by markings on the photos, dust stuck to oily fingerprints usually.
 You could try wiping the print with cotton wool, or an unused soft paint brush, then blowing any bits off with a blower thingy* before scanning.
 [* don't blow with your mouth it can add spots of saliva which are visible on the scan].

Re: thumbnail, you mentioned previously that the photo software you were using was not updating the thumbnails,
 so this would explain why the "cut out" has the thumbnail of the full image.
« Last Edit: 04/02/2010 05:53:38 by RD »
 

Offline neilep

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #10 on: 03/02/2010 23:25:39 »
...but how did you access the full picture ?


....the photos seem so clean before placing on the scanner.....but..i guess the scanner can see more than I can........ok...I'll wipe and see if it gets better rather than investing in a blowy thingy !
 

Offline RD

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #11 on: 03/02/2010 23:38:19 »
...but how did you access the full picture ?

The [out-of-date] thumbnail is incorporated in metadata of the image you posted.

....the photos seem so clean before placing on the scanner.....but..i guess the scanner can see more than I can........ok...I'll wipe and see if it gets better rather than investing in a blowy thingy !

A quick way of getting rid of the dust on the digital image is using "erode" then "dilate" in GIMP, e.g. ...



Erode and dilate are in the GIMP filters menu under "Generic".

This "erode" then "dilate" process does soften the image slightly: I'd sharpen the after image a bit (by about 20 GIMP points).
« Last Edit: 04/02/2010 00:00:34 by RD »
 

Offline neilep

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #12 on: 04/02/2010 00:01:23 »
Thanks RD..I shall now remove metatdata from images I use from now on...I guess it might be time for me to finally give GIMP a try....it just seems ...well......very complicated for a simple sheepy !!  ::)
 

Offline RD

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #13 on: 04/02/2010 00:51:28 »
Here is a similar clean-up effect using Irfanview rather than GIMP ...



The result is sharper than GIMP, but there are more bits of dust left behind,
This is the tradeoff: sharp-image dust obvious, blurry-image no dust visible. 

Best to clean the actual print first as the digital cleaning does modify (soften blur) the image.

Irfanview is a smaller simpler quicker programme than GIMP, but is only available for Windows.

[BTW £5 - £10 for a puffer thingy is a good investment as it can save hours of digital retouching,
 and you can clean your camera/computer with it too. Also cheaper than canned air in the long run].
« Last Edit: 04/02/2010 05:29:48 by RD »
 

Offline yor_on

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #14 on: 04/02/2010 01:20:56 »
I think it has to do with the static electricity Neil. Try to degauss it. The scanner and possibly the photo too. It's EM-'dust' that disturbs the scanning I guess

(Isn't 'degauss' the proper word here?)

==
Just don't ask me how to do such a thing. I know you British did it with whole warships under ww2, so one little scanner shouldn't be too much trouble, should it?
« Last Edit: 04/02/2010 01:22:43 by yor_on »
 

Offline RD

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #15 on: 04/02/2010 02:19:42 »
The dust is sticking to fingerprint residue, not due to static electricity.
It's like how those CSI guys "dust" for latent fingerprints (with aluminium powder).


I shall now remove metatdata from images I use from now on

Using IfranView's "Save for web" (RIOT plugin) instantly creates a version without your old full-image thumbnail,
(and gets rid of all the other metadata too)

RIOT is available as a "stand alone" programme for windows, or as a plugin for IrfanView or GIMP ... http://luci.criosweb.ro/riot/
« Last Edit: 05/02/2010 11:00:26 by RD »
 

Offline Geezer

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Re: Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #16 on: 04/02/2010 04:58:46 »
I think it has to do with the static electricity Neil. Try to degauss it. The scanner and possibly the photo too. It's EM-'dust' that disturbs the scanning I guess

(Isn't 'degauss' the proper word here?)

==
Just don't ask me how to do such a thing. I know you British did it with whole warships under ww2, so one little scanner shouldn't be too much trouble, should it?

Degaussing won't help in this situation. Degaussing is used to remove unwanted residual magnetic fields (think permanent magnets) but it will not remove static charge.
 

Offline yor_on

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Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #17 on: 08/02/2010 02:39:55 »
Ah, knew that..
(naah:)

*Mutters angrily as he stomps away, damn them prefessers, always soo bl*y right"

 

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Why Does My Scanner Add Bits To my Scans (Of Photos)?
« Reply #17 on: 08/02/2010 02:39:55 »

 

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