tips for scanning photographic prints with a flatbed scanner

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Tips for Scanning Photographic Prints with aFlatbed Scanner

Introduction

A three-colour flatbed scanner is currently (early 2004) the commonest practical device available for making digital copies of

analogue 35 mm prints. The smaller cheaper 'paper-port' type scanners which move the paper past the scanning head normallyproduce too low quality images and dedicated photograph scanners are both more expensive and less versatile at scanning othertypes of documents than a general purpose flatbed document scanner. Rephotographing a print with a digital camera will soonbecome another possibility but aligning the components accurately is awkward and as (good) digital camera resolution iscurrently only about the same as (good) analogue prints, it does not leave any resolution in reserve. Therefore a flatbed scanneris currently the norm for non-professionals.

Here are a few tips for getting a good result that I've got from scanning approx. 350 of my high resolution 'arty' photographsover the past three years.

Scanner Resolution

The scanner I use (Cannon CanoScan N 650 U) has 600 pixels/inch optical resolution which is ample as it gives a9 megapixel image from a normal 6"x4" print. The resolution is limited by the film grain not the pixellation. Only if you have verysharp images with lots of fine detail on exceptionally very fine grain film then would more scanner resolution be vital. Make surethe scanner can live up to its claimed resolution though, a poorly made scanner might still be able to provide a high resolution inpixels but might distribute them irregularly causing lines across the scan axis (from the scanner head being mechanically movedjerkily), might have faulty scan head elements causing lines parallel to the scan axis or might have noticeable noise in itsimages.

Some scanners can provide a scan at greater than the optical resolution of the scanner. This is pointless as it is just done byinterpolation between scanned pixels, a task which a picture editing program can do easily, and simply wastes time by increasingthe file sizes. Set the scan resolution to the optical resolution of the scanner unless that is unnecessarily high (600 pixels/inchwas high when I got the scanner but 1200 pixels/inch is now common), in which case you can set it to downsample before savingto save time if you want.

Dust Avoiding

Dust is the biggest inconvenience with scanning. Dust specks that are too small to see on the print show up terribly as whitespots on scans as if they were 0.1-0.2 mm across. This is because a dust speck is not flat like the print and reflects light from itssides so appearing on neighbouring pixels not just the one at its own position.

The obvious precautions of cleaning the scanner bed glass, taking care not leave smears, & blowing the dust off the printsgets rid of most of the specks but many will still creep into the scanning process and need to be tediously removed from thescanned image. If the scanner is not hermetically sealed then it might also need dusting inside of the other side of the glass.Dust on that side will be out of focus and therefore show up as pale patches of fuzziness on the scan that will require more workto remove than small sharp dust spots.

Whilst at it, you might as well also clean the computer monitor. Although dust on that will not affect the scan, it is irritatingto be try to edit out a mark from a scan only to find that it is just muck on the computer screen!

A catch to watch out for is automatic dust enhancement in the scanner. Of course it is not called 'dust enhancement' but'sharpening'. I once scanned about 100 photographs before looking at the scans close up on screen and found them terriblydusty. I had rebuilt the computer and forgotten to go through all the scanner software settings. I had left the 'unsharp mask'image sharpening, which was enabled by default, switched on & it had enhanced all the dust spots! After tediously manuallyediting the dust out some of those I gave up and rescanned the lot. It has almost given me a phobia against the 'unsharp mask'(which I had barely taken notice of before but turns out to be one of the most common automatic image enhancement methods

in digital photography)!

Gamma Compensation

This section is a bit technical. If you are not interested in the explanation, just set the 'gamma correction' in the scannersoftware for a monitor 'gamma' of 2.2 or scanner 'gamma' of 0.45 (which is probably the default value anyway) and skip to thenext section.

The need of a gamma setting is mostly a historical accident. The most obvious ways for a brightness to be represented as anumber is for the number to be simply proportional to amount of light. Another sensible possibility would be for it to beproportional to the logarithm of the amount of light as that approximates chemical photographic film and human visualperception. Instead the numbers are proportional to the amount of light raised to a power. This originates from the way thebrightness of the light emitted from the phosphor in a TV's cathode ray tube varies with its electron accelerating potentialdifference. That brightness is approximately proportional to the p.d. raised to the power of 2.5, a quantity which was arbitrarilycalled 'gamma'.

That bit of physics should not concern users as it could have been compensated for in the electronics but it was found that TVviewers preferred the artificially high contrast & glowing colours it gave so it was only compensated to around 2.2 not to 1.0. IBMcompatible PCs originally had cheap monitors so they used TV technology with that high gamma (Macintosh PCs & SiliconGraphics workstations had better correction at 1.8 & 1.4 respectively as they were aimed at professional graphics markets). Toget correct colours for artwork, this had to be compensated by 'gamma compensation' for a gamma of 2.2, i.e. raising thebrightness levels to the power of 1/2.2 = 0.45 before sending them to the monitor. Sensibly this would have been done in the PCvideo output chips but that would have needed those chips to be told when to display like a TV (for games etc.) and when to

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display realistically (for art etc.) but neither M$ DOS nor early versions of M$ Windows bothered with gamma considerations.Therefore it was bodged up by actually having the compensation in the brightness values in the image files, i.e. putting anopposite distortion in the image to cancel the distortion on the monitor. Nowadays it could all be corrected automatically to eachmonitor, scanner & printer with ICC colour profiles but unfortunately for backwards compatibility a compensation of 2.2 withinthe image data had become the de factostandard. From there it became the de jure'sRGB' standard which essentially says"Unless there are ICC profiles to specify better, assume gamma of 2.2 on the output device." (technically it is a power of 2.4piece-wise curve with a low brightness cut-off but it is virtually identical to a simple gamma 2.2 curve). The digital cameraindustry adopted JPEG compression as their standard image format with EXIF tagging and sRGB gamma compensation,presumably so that images files would be viewable on default PC setups without alteration. Hence digital photograph printingservices output at gamma 2.2 too. Therefore if one wants to show scans to others on the WWW, by e-mail, etc. or to have scansprinted out by normal digital photograph printing companies, one is best off with 2.2 gamma compensation even though 1.0 is

intrinsically more logical.

To test that, I scanned a test photograph at 6 different gamma compensation values and had them printed by a digitalphotograph printing company (it was my current favourite, Photobox, but other ones produced the same conclusion) andcompared them to the original. The 2.2 one was closest to the original.

0.6 1.0 1.4

1.8 2.2 2.6

Original

Automatic Calibration

Most scanners probably have some automatic calibration option. It is probably a good idea to use it as at least often assuggested in its instructions, after a long period of disuse & after physically abusing it (e.g. bouncing it home on the back of mypushbike!). The main effect of automatic calibration on my scanner is to compensate for different sensitivities of the scanningsensors. When it is out of calibration, images are defaced by bands of different brightness parallel scan axis.

Scanning

Scanning itself is fairly trivial. Try to align the print parallel to the sides of the scanning area to save having to rotate theimage afterwards. To minimise the motion of the scan head, and hence the time taken to scan, arrange the print with its shortedge parallel to the scan axis and place it at the edge of the scanner where the scan head starts moving from. Scan a slightlylarger area than the photograph to allow for slight misplacement.

Ensure that the photograph is pressed flat. Some photographs have a strong curve to the paper which may need a weight(e.g. a book) put on top of the scanner lid to squash it fully flat. Edges which bow away from the glass can get a bevelled effect

in the scan where they blend towards white from light leaking in the sides so requiring more cropping.

Rotating & Cropping

Open the image file in a raster image or photograph editing program such as Jasc Paint Shop Pro, GNU Gimp, CorelPhotopaint, DL&C Picture Window Pro or Adobe Photoshop (I've not found the simple editors which come with scanners, M$Windows or M$ Office to be much good), correct the rotation if it slipped on the scanner, and crop off the scanner background.This is easy. Unfortunately the next editing stage is not.

Dust Removing

The most tedious part of scanning with a normal flatbed scanner is getting rid of the white specks from the inevitable dustmotes. Good image editing programs have several dust removing tools varying from almost fully automatic to almost fullymanual. The automatic ones are much less time consuming than the manual ones but remove fine detail in the images alongwith the dust. Commonly recommended automatic tools include:

Salt & Pepper Filter:This looks for white (or black) splodges of a specified size an replaces them with an interpolationfrom nearby surroundings. It is almost ideally suited to dust speck removal.Despeckle:Similar to the Salt & Pepper Filter but simpler in that it assumes the specks are single pixels. That is useful forremoving digital camera 'hot pixel' noise but not so suited for scanned dust specks which can spread across several pixels.Median Filter:Replaces each pixel with the median value of its surrounding pixels thereby removing pixel values thatdeviate far from neighbours. I find this blurs the image too much though.


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Edge Preserving Smooth:Blurs out areas it reckons should be smooth to remove noise whilst leaving sharp edges intact.It is not good at removing dust because specks can count as sharp enough edges to keep and because it loses natural filmgrain detail in smooth regions.Soften / Blur:These fuzz out each pixel onto surrounding ones losing fine detail. They are damage the rest of the imageseverely but are often recommended because they are commonly available in crude image editing programs that don'thave specific dust removal tools.

My current preference is the 'Salt & Pepper Filter' is Paint Shop Pro 8. For Photoshop Elements users, I think the nearestequivalent is the (ambiguously named) 'Dust & Scratch Filter', & for GIMP users, it is the (misleadingly named) 'Speckle Filter'. Imight be wrong though as I have not tried either of those personally and only based the equivalence on their descriptions inon-line manuals.

I use the settings of: 'Aggressive action' turned on so that it fully removes not just tones down the specks; 'Speck size' of 3to 5 pixels which is the typical size of my dust specks; and 'Include all lower speck sizes' turned off so that it does not removethe film grain as well. However even that filter does some damage to other areas of the images, for example mistaking specks oflight between leaves of distant trees for dust specks. Therefore I only apply it areas of the image that have dust spots. There areseveral ways of applying a filter to only specific areas of an image and they depend upon the program. In PSP 8 they include:

Masked Layer:Duplicate the whole image into a higher ' layer', apply the filter to the whole original bottom layer, add anempty (i.e. 'show all' or 'white') mask layer to the unaltered higher layer, hide the mask visual overlay but select the maskas the active layer & draw on it with a black soft edged paintbrush tool of size slightly bigger than a typical dust spot.Wherever is painted over with that tool will cause the unaltered layer to be hidden and the dusted layer underneath toshow through. It effectively acts as a dust removing paintbrush tool. If one has not the time to select individual dust specksthen simply use a bigger brush. The layer duplication, filtering & mask adding setting up can be recorded as a macro.Alternatively it can be done with the higher layer filtered, the mask initially fully black & the brush white. The result is thesame.Transparent Layer:Instead of using a mask, one can just use an eraser tool to make holes in the unaltered layer. Iteffectively acts as a dust eraser tool. It is simpler to understand than using a mask but less easy to correct mistakes in

(erased bits are gone but a mask can be re-edited).Selection:If layers are too much hassle, just select the dusty areas as quick loops with a freehand selection tool beforeapplying the filter to limit it to those areas. This is very quick for large selections (e.g. all the sky) but is far slower thanlayers if one wants to select down to individual specks.

I normally zoom my images to about equal to the resolution I intend to eventually save them in (as I use a 1024 pixel widescreen for 2048 pixel wide final images I zoom to about double linear size). It is not necessary to zoom to the full resolution ofthe scan. At full magnification many insignificant speckles would look dauntingly like dust. It is necessary to zoom to the aboutthe final resolution though as otherwise some dust might be missed so the image will look fine for now but not if it is printed outor displayed on a bigger screen in the future.

If your image editing program does not have a suitable filter or does not support layers & you can run Win32 programs thenthere is free dedicated program which does essentially the same from Polaroid, the Polaroid Dust & Scratch Removal Tool. Itallows one to create a 'mask' (which acts like a PSP 'selection') & apply an automatic dusting algorithm similar to a Salt & PepperFilter. The procedure is: open the image; zoom in; use the 'Mark Dust' tool to select the dust point by clicking on them; use'Create Mask from Dust Points' to find & show dust points within the marked areas; 'Remove Dust and Scratch Points' to remove

the dust; and then save the cleaned image.

Unfortunately some dust specks will be left because they were bigger than could be safely removed by filtering or becausethe background that needs to be patched in has too distinct edges or patterning. For those one needs to manually draw over thedust (if using layers remember to merge them or at least make the unaltered layer the active one). The Clone Brush Tool is bestfor that:

Clone Brush Tool:A manually controlled tool similar to a paintbrush tool but it copies from one area of the image toanother. Typically one chooses a similarly coloured & textured area to copy from by a click of the secondary mouse button& then draws over the dust by holding down the primary mouse button. It is a general purpose drawing tool but isespecially useful for dust removal as it can replace a speck with a realistically coloured and textured area, rather than flatcolour, easily.Scratch Remover Tool:A tool specifically for selecting a blemish and automatically removing it. It seems rather pointlessto me as selecting takes as long as painting out with the Clone Brush Tool and getting the settings correct to seamlesslyremove the blemish is slower than choosing an a place to clone from.Paintbrush Tool:It could be used but selecting colours to match each area & texturing to prevent the painted out speck

looking unnaturally flat but is really tedious. I've seen someone with more artistic skill (& much more patience!) than meedit pictures that way in Paint Shop Pro having not thought of using a Clone Brush Tool for more than its advertised use ofduplicating large image elements. It was frustratingly slow to watch! If your drawing program is so crude that that is allthat is available (I'm thinking of the pathetic M$ Paint 5 which was bundled with M$ Windows) then get a better one.

My current procedure is therefore: use a Salt & Pepper Filter with a mask layer to delete all dust spots other than the(hopefully few) that are on awkward backgrounds; then use the Clone Brush Tool to remove the remaining ones.

Set the Clone Brush Tool to have a feathered edge (i.e. fades out to transparency rather than an abrupt cut-off) so that thecopied bit blends into its surrounds well. Setting it central opacity at about 75% (called 25% transparency in some programs) orless and copying from different areas if multiple strokes are needed to hide the mark will also improve the seamlessness of thepatching but, of course, takes more effort.

Dust Avoidance

Although avoiding dust is almost impossible, in some circumstances it can be virtually invisible. As the dust specks appear

white, dust will obviously be less visible in light areas. Similarly textures which are randomly speckled like dust will hide it.

Of course, scanning new prints before handing them round your friends or adding them to your collection in a file or albumreduces the amount of dust & damage you will have to undo.

The size also matters. If you have a print bigger than a standard 6"x4" one, then scan that larger one instead and reduce thesize after scanning. This shrinks the dust spots. In addition, one can use automatic dust removal tools, even simple blurring, first


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without significant loss of image quality as the scale of the lost detail can be less the the pixel size of the final image. Evenscanning a 10"x8" print, which is not even twice as wide as a standard one, applying the Salt & Pepper Filter uniformly across thewhole image and then reducing it from 6000 pixels across to 2000 can produce a dustless good resolution image without manualdusting. Of course you might be tempted by the reduced relative grain size on a big print to have more pixels in the final image,in which case you will have even more of an area to dust!

Also think about whether you really need so high an eventual resolution or not. If the picture is primarily for the subjectmatter (such as holiday snaps of grinning friends & family, a record of how a room looked before redecoration, or somethingkept for nostalgia) rather than as piece of artwork then the grain-level detail is probably not needed. If that is so then a smallerfinal number of pixels will be acceptable so you can apply the above size reduction trick as if scanning a big print and end up witha lower resolution print which not only saves dusting but saves storage space.

Sometimes what looks like dust can be a genuine part of the scene. I was once just about to dust some dark specks out of aphotograph of a meadow when I zoomed in and saw that they were images of summer insects hovering over the flowers. Fallingsnow & rain drops illuminated by a flash can also look like dust. Of course, one might feel like edit out the midges as well as thedust if one has been bitten by them on that nice summer's day!

Scratch Removal

Scratches in newly printed photographs & well stored negatives are rare but small curved white lines from fibres that havegot into the printing machines & small splodges from emulsion defects are relatively common. They can are normally easy toremove with the Clone Brush Tool and take far less time than removing dust because there not many to do (typically averaging 1blemish per print compared to 10-100 dust spots!).

Colour Correction

By this I mean colour correction to make the scanned image look like the original photograph not changing the colour fromthe original (which I feel is a bit like cheating :-) ). I am fussy about colour fidelity but, after making allowance for the inevitablecolour mismatch (monitors have lower dynamic range than photographic film and are luminous rather than reflective sources), Ihave found the colours are usually reasonably similar without needing any tweaking so I normally don't bother with adjustments.

An exception is for sunsets, silhouettes, dark backgrounds etc.. The lower dynamic range of monitors compared to film tendsto make the striking deep blacks look an unimpressive blotchy dark grey. To compensate for that I darken them with a 'Curve'set with the full scale black & white points unchanged but with a lower than 1:1 gradient for the darkest 10 % or so. A similareffect could be done a bit simpler but with less control using a gamma adjustment or with a bit more control using histogramadjustment.

For really dedicated people who are concerned about contrast, the limitation of 256 brightness levels per colour channelintrinsic to most computer image formats can be bypassed by using a scanner which allows scan data to recorded at more than 8bits per channel, typically 16 bits. The resulting data can be imported in some photograph editing programs and one's ownmapping between those levels and the restricted monitor dynamic range applied before decimating it down to a normal 8-bitimage format. That is far too much hassle for me. If you want to find out more there is an article about 48-bit colour digital

image processing on Norman Koren's site.Of course, check that it is not simply the colour balance on your monitor which is at fault before tweaking the colour in the

image files. Professional ways of calibrating a monitor are slow & expensive. A reasonable amateur alternative is to make a testimage with varied colours, shades etc., get it printed by a reasonably trusted company (or several companies to cross-check),assume their printer has been calibrated, put the print next to the monitor with the room lighting as normal (but not lit just bythe monitor's varying light!) and adjust the monitor settings to get as close as possible to its colours. Remember that a monitorcalibrated to match printed material under daytime sunlight will be severely out of calibration under night-time artificial lightingand vice versa because human visual perception automatically adjusts to the different incident light reflecting off the printswhereas very few monitors automatically do so.

Check the Cropping

This is the final chance to check & correct the cropping before reducing the image to its final size. It is easy to have been toomeagre with the cropping and have a fine white line (my scanner's background is white, yours might be different) down an edgeof the image near a corner which was not noticed because it was abut the distracting window edge in the editing program. If it

annoyingly shows up in the future when the image is put on a plain background or is printed, it will give one the dilemma ofcropping the compressed image further (and possibly stretching it to match the size of the others) so losing more detail fromrecompression, rescanning it or remembering to take the edge error into account every time one reuses it subsequently.

The most efficient way I've found of checking for this is to save the image at this stage (without reducing resolution & withlow compression) then add a black border (white if your scanner has a dark background) and look at the corners. I have a batchprocess sets this up for me on many image files at once.

Compression

Now, at last, to save the image. Besides the file name (which can be changed later), two things need to decided: the numberof pixels in the image and the amount of compression. Both of these degrade the image so they need to be chosen carefully. Iffile size is of no concern to you then you can save it without decimation & without lossy JPEG compression but such detail isunnecessary given the grain limitations of the film and the huge files will be slower to work with.

I decimate the number of pixels down to 2048 on the widest edge (with the other edge automatic to maintain the aspectratio). This is fairly arbitrary and might be a bit unnecessarily low but is somewhere near the maximum useful number of pixelsfrom a 6"x4" print. I chose it because my original intention for scanning my photographs was just as PC desktop wallpaper (Ioriginally intended only 20 or so scans not 300!). My best monitor happened to be 1024 pixels across at the time and I arbitrarilydoubled it lest I got a bigger or higher resolution monitor in the future. When reducing the number of pixels use a method whichinterpolates across pixels not one which simply removes lines of pixels.


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The amount of JPEG compression is difficult to describe as there is no standardisation of how different amounts ofcompression are numbered or labelled or even whether big or small numbers correspond to the most compression. In Jasc PaintShop Pro 8, I use compression level 22 which is similar to level 50 in Corel Photopaint 7. This is was simply from decreasing thecompression Photopaint in steps of 10 until it did not damage fine details too much. Maybe I should be compressing a lot less asthe compression in my digital camera (an Olympus C50) is approximately equivalent to Paint Shop Pro level 8 at 'High Quality'and only level 2 at 'Super High Quality'!

Renaming & Filing

If you have not yet named the images files intelligibly then name them now. I leave the naming to last so I can see all thefinal scans from a film at the same time and choose a level of detail in the naming sufficient to distinguish them but not

excessive. I would like to include location, subject, date, film number & memorable features in the file name but unfortunatelycompatibility with the CD file system limits names to 64 characters including the '.jpg' (& that is the 'Joliet' enhancement of thebasic ISO CD-ROM spec; the original only allowed pathetic M$DOS 8+3 character file names!). One could leave the file names aswhatever the scanning software or editing program defaulted to & index them elsewhere but it is much more convenient forsearching if the file names are meaningful. One can store extra text information in the image file (in either the original IPTCformat or digital camera EXIF format) but not all search programs or even graphics programs can read that data so it is best toinclude the main details in the file name as well.

Then one has too choose how to structure the directories to store the images in (unless one is simply going to plonk them alltogether in one flat directory). The difficulty is in choosing the hierarchy as there are several obvious primary groupings includingthe subject matter, style, location, date & (if you have photographs from friends) photographer. The same dilemma of coursealso applied to filing the prints in the past. I use a slightly inconsistent mixture of filing some by location & some by subjectmatter depending on which I feel is most significant for each photograph. One can duplicate the same photograph under multipledirectories but having multiple copies in a database makes keeping consistency awkward. Better would be have a single copy ofeach linked from multiple places. This could be done using the hard linking facility of Unix file systems, dedicated iPhoto indexingprogram of a Macintosh links or some homemade HTML index. Unfortunately there is not a system which is easy to maintain &

future-proof yet compatible with current Windows, Linux, Macintosh & CD filing systems so I stick to a plain old directory treestructure.

My Macros/Scripts

Here are the editing scripts I used for batch processing images in Paint Shop Pro. They are written in Paint Shop Pro 8 Pythonso they are unlikely to work in other editing programs. Apologies if you have one of them. You will have to do it manually, findequivalent scripts elsewhere or write your own. They are released freely under GPL and used at your own risk (though that riskshould be minimal if you run them as restricted scripts (which prevents them doing anything outside PSP), backup your imagesfirst & check that the results are to your liking before deleting the backups).

Create a dusting layer: It copies the image to the new layer, dusts the new layer with the Salt & Pepper Filter & masks outthe whole dusted layer. It is essentially just a recorded macro. It is not intended for batch processing so it ends byswitching to the paintbrush tool with the mask layer active & zooms in a bit ready for one to brush out the dustCreate a cropping checking image from an image: It adds a black border, rotates the image to landscape to fit a monitor

better, extracts the 4 corners of the image discarding the rest and joins them together into one image for a quick visualcheck. It also puts a thumbnail of the original image in centre so one does not have to look up which original it came fromby name. Edit the constants in the code to your preference of sizes. I've substantially reprogrammed it in Python from theoriginal recorded macro so that it will adapt automatically to different image sizes (but is still many times slower than if Ihad programmed it from scratch).Shrink an image to 2048 pixels in the maximum extent: This is similar in action to the example thumbnailing macro whichcomes with PSP but that sets the new image's resolution information to an arbitrary constant whereas this has beenreprogrammed to calculate it properly from original & final image sizes. Edit the constant in the script to your final imagesize preference.

Note that the compression level when batch processing with PSP scripts is not set by the script itself but by the preferencesin the batch processing dialogue box even though they (in PSP 8.1) appear disenabled unless writing to a new directory soremember to set that (by switching to 'Save as New Type', setting the preferences then setting back to 'Overwrite').

Professional Alternatives

A dedicated negative scanner theoretically can give a higher number of useful pixels in the final print because it is limitedonly by the grain in the negative film not by both that and the grain in print paper. Also the dynamic range possible fromscanning a negative directly is considerably higher than indirectly via a print. However, because the negative is smaller, theoptical resolution of the scanner needs to be higher and dust can be even more of a problem.

Expensive specialist scanners can avoid the dust problem by using infra-red light (or some other means) to detect the dustand then automatically interpolate across the specks without disturbing the rest of the image. This is essentially the same as theabove dusting process but with the dusting mask layer automatically created from the infra-red colour channel (dust absorbsinfra-red very differently to normal photographic paper).

I have tried having scans made by a film processing company at the time they developed the negatives but I was sodisgusted with the result that I have not ordered such scans since. The Kodak 'Picture CD' was advertised as "high resolution"but the scans were only 1536x1024 pixels, less than I routinely produce from a flatbed scanner, and the unintelligent complaintline operator did not seem to understand the concept of scanning resolution as distinct from out of focus originals. I later foundout the low resolution was a ploy by Kodak to stop their 'Picture CD's competing with their 'Photo CD's which were the samething but at proper resolution & marketed to professionals at an absurdly high price.

Epilogue

The above article was written mainly in early 2004 based experiences of scanning photographs between 2001 & 2004.Already (it is 2006 as I write this epilogue) technology has moved on.


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In particular consumer-grade negative/slide scanners have improved in three significant ways. Firstly, the resolutions haveincreased to the extent that one can get higher resolution on the resulting scan from such a negative scanner than fromfilm-paper grain limited scanning of prints. Secondly, they often incorporate automatic dust speck removal systems that used tobe only available in professional scanners. Thirdly, these scanners are now available at reasonable prices (around 120 &falling).

If were starting scanning my collection now (and knew that I was going to be scanning so many photographs - it started asjust a few scans for desktop wallpaper!) then I would buy such a scanner both because of the higher dynamic range & slightlyhigher resolution I could have got would enable reprints as good as the original prints without tweaking but primarily because ofthe time saved from dust removal. However I have now completed digitising those photographs from my archives I want topreserve and it is not worth me rescanning them.

However, I will keep this webpage in existence because there are still many people who have a flatbed scanner & want toscan some photographs accurately but not scan a batch of hundreds.

By Andrew Hardwick.Distributable under GPLfreeware licence.

Written 2004/2/13.A few more tips added 2004/3/18, 2004/4/10 & 2004/8/17.

Added epilogue 2006/1/26.Spelling corrections 2008/3/4.

More added to epilogue 2010/6/10.Linked in la rger pictures 2011/6/20.

Available on-line at http://duramecho.com.


tips for scanning photographic prints with a flatbed scanner

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