[digiKam-users] Fwd: Hope this is not OT

[Errol Sapir]

Hi Gilles

The idea isn't to invert colour but to enhance colour. The slides have faded and the original colours aren't alive. The link shows a photo that has faded.

Errol

https://mega.nz/file/QxlEAIbI#gwt5Omb5cSa1-WPeDxVlTdtyoNkwZYdeUC9xVp9L6b4

On 12/05/2021 11:50, Gilles Caulier wrote:

Le mer. 12 mai 2021 à 04:39, Errol Sapir <[hidden email]> a écrit :

Hi All

I am now trying Manjaro KDE after many years of Kununtu. Of course I am also planning to transfer (or redo) my Digikam from Kubuntu to Manjaro. I have however a photo question that doesn't specifically apply specifically to either of these programs. As I said in the subject I hope it isn't OT but as it is photo connected and I hope Digikam can help as well I would appreciate the help of anyone who can. If it is OT the moderators can remove my post and I will understand.

I am transferring all my slides (and eventually negatives) to digital format. I am looking for a one-click solution (program) that will restore colours back to normal.

You want mean to invert color ? If yes, ImageMagick is your friend, especially -negate option:

https://superuser.com/questions/1194468/invert-colors-with-imagemagick

This can be scripted of course to parse and process automatically all files from your collection. And of course, all can be done de facto under Linux from command line.

Else, In digiKam, Invert Color tool from Batch Queue Manager can be used. Create a new Queue, assign items to process, configure the output options (path, file name, etc...), assign Invert tool + the convert format if necessary, and... you can take a coffee.

Best

Gilles Caulier

[Gerd Muncke]

Hi Errol,

I think you've got tough luck. While I also scanned lots of slides and even more 35-mm colour negatives very successfully with my Epson V800 I only had to do minor corrections, most of them with the digikam built-in editor.

I tried the same with your picture and found that it requires a lot of patience and time (which I'm lacking currently) to somewhat get the right balance of colours.

The software that goes with my scanner is indeed very good and does already a lot of work for me. Draw your own conclusions from this.

All the best

Gerd

On Wednesday, 12 May 2021 19:48:24 CEST Errol Sapir wrote:

> Hi Gilles

>

> The idea isn't to invert colour but to enhance colour. The

>         slides have faded and the original colours aren't alive. The

>         link shows a photo that has faded.

>

> Errol

>

>

>

>

> https://mega.nz/file/QxlEAIbI#gwt5Omb5cSa1-WPeDxVlTdtyoNkwZYdeUC9xVp9L6b4

>

>

>

>

>

>

>

>

>

>

> On 12/05/2021 11:50, Gilles Caulier

>         wrote:

>

>

>

>

>

> Le mer. 12 mai 2021

>               à 04:39, Errol Sapir <[hidden email]>

>               a écrit :

>

>

> Hi All

>

> I am now trying Manjaro KDE after many years of

>                   Kununtu. Of course I am also planning to transfer (or

>                   redo) my Digikam from Kubuntu to Manjaro. I have

>                   however a photo question that doesn't specifically

>                   apply specifically to either of these programs. As I

>                   said in the subject I hope it isn't OT but as it is

>                   photo connected and I hope Digikam can help as well I

>                   would appreciate the help of anyone who can. If it is

>                   OT the moderators can remove my post and I will

>                   understand.

>

>

> I am transferring all my slides (and eventually

>                   negatives) to digital format. I am looking for a

>                   one-click solution (program) that will restore colours

>                   back to normal.

>

>

>

>

>

> You want mean to invert color ? If yes, ImageMagick is

>               your friend, especially -negate option:

>

>

> https://superuser.com/questions/1194468/invert-colors-with-imagemagick

>

>

> This can be scripted of course to parse and process

>               automatically all files from your collection. And of

>               course, all can be done de facto under Linux from command

>               line.

>

>

> Else, In digiKam, Invert Color tool from Batch Queue

>               Manager can be used. Create a new Queue, assign items to

>               process, configure the output options (path, file name,

>               etc...), assign Invert tool + the convert format if

>               necessary, and... you can take a coffee.

>

>

> Best

>

>

> Gilles Caulier

--

Gerd Muncke

 An der Stalden 2

78337 Öhningen

Germany/Deutschland

Tel: [phone]

Mobile: [phone]

[Sveinn í Felli-2]

Þann 12.5.2021 17:48, skrifaði Errol Sapir
> Hi Gilles
>
> The idea isn't to invert colour but to enhance colour. The slides have faded and
> the original colours aren't alive. The link shows a photo that has faded.
>
> Errol
>
> https://mega.nz/file/QxlEAIbI#gwt5Omb5cSa1-WPeDxVlTdtyoNkwZYdeUC9xVp9L6b4
>

Hi Errol,

Scanning and repairing old slides can be a complex matter; it depends on
brands of film, on previous storage of the slides, and on type of mount
(what kind of frame they've been mounted in), and possibly other factors
too.

I've repaired several slides similar to the one you shared, guess this
one is an AGFA-GEVAERT positive film, possibly a FUJIFILM. Sometimes a
generic automatic filter like "Equalize" will do the trick; problem is
that often a great deal of image info will be lost. Other problem is
that usually not all the original photos were ever "correctly" exposed.
Existential problem; do you want to be faithful to the original images
or just get decent usable photos right away?

I searched the web thoroughly for info on how to do this with
FOSS-software; there are some scripts (mostly for GIMP) for certain
types of film of certain age (yes, the year of production counts), but
the majority of those doing such work resort to using the commercial
extensions available for Photoshop. Those are sort of databases with
measured decay of various types of film, along with commands for
corresponding filters.

Nevertheless I found a neat procedure for doing this in GIMP (can't find
the source right now); Take one of a batch similar slides (from one
shooting, one year or similar exposure), demount it from the plastic
frame (bad luck if it's glued into a paper frame) and scan the whole
area, including the perforated strip on both sides, where normally there
should be markings in clear letters with the brand name and number of
the image.

In "Levels" histogram mode with the eyedropper-tool in "All channels"
section, change the white-point to a decent sample of a letter on the
strip (transparent = white), similarly take the black-point from the
surrounding black/opaque frame, then pick a gray-point (where a gray
area should be) from the image itself. This way you're compensating for
the "natural" decay of the corresponding film (of a certain brand,
certain age). You may then have to fiddle with all the color-components
separately to further enhance colors. The most important is to save the
result as a preset, and then use that preset manually on each image
(with further enhancements like sharpening etc.) or use it on several
images with GIMP --headless on the command line.

You could also use the values from this preset to make settings for the
BatchQueue Manager in Digikam or some script for ImageMagick.

But as stated above, this procedure only compensates for the natural
decay of the film itself, not the decoloration of the image due to
sunlight or overuse (number of passages in a projector).

For those who like the technical side of things:
<http://www.lionhouse.plus.com/photorestore/Restore2.pdf>

Good luck,

Just some thoughts - good luck restoring your slides,
Sveinn í Felli

> On 12/05/2021 11:50, Gilles Caulier wrote:
>>
>>
>> Le mer. 12 mai 2021 à 04:39, Errol Sapir <[hidden email]
>> <mailto:[hidden email]>> a écrit :
>>
>>     Hi All
>>
>>     I am now trying Manjaro KDE after many years of Kununtu. Of course I am
>>     also planning to transfer (or redo) my Digikam from Kubuntu to Manjaro. I
>>     have however a photo question that doesn't specifically apply specifically
>>     to either of these programs. As I said in the subject I hope it isn't OT
>>     but as it is photo connected and I hope Digikam can help as well I would
>>     appreciate the help of anyone who can. If it is OT the moderators can
>>     remove my post and I will understand.
>>
>>     I am transferring all my slides (and eventually negatives) to digital
>>     format. I am looking for a one-click solution (program) that will restore
>>     colours back to normal.
>>
>>
>>
>> You want mean to invert color ? If yes, ImageMagick is your friend, especially
>> -negate option:
>>
>> https://superuser.com/questions/1194468/invert-colors-with-imagemagick
>>
>> This can be scripted of course to parse and process automatically all files
>> from your collection. And of course, all can be done de facto under Linux from
>> command line.
>>
>> Else, In digiKam, Invert Color tool from Batch Queue Manager can be used.
>> Create a new Queue, assign items to process, configure the output options
>> (path, file name, etc...), assign Invert tool + the convert format if
>> necessary, and... you can take a coffee.
>>
>> Best
>>
>> Gilles Caulier
>>
>

[Errol Sapir]

Hi Sveinn

Thank you for your detailed explanation and link to the technical explanation. If I understand your solution seems to be in Gimp. I will try and apply some of your methods and see where it takes me. My main aim is to get decent usable photos right away with the option of further tweaking the better ones after restoration. I will report back here results. Meanwhile if there are any further suggestions I would appreciate them.

TIA

Errol

On 17/05/2021 14:57, Sveinn í Felli wrote:

Þann 12.5.2021 17:48, skrifaði Errol Sapir

Hi Gilles

The idea isn't to invert colour but to enhance colour. The slides have faded and
the original colours aren't alive. The link shows a photo that has faded.

Errol

https://mega.nz/file/QxlEAIbI#gwt5Omb5cSa1-WPeDxVlTdtyoNkwZYdeUC9xVp9L6b4

Hi Errol,

Scanning and repairing old slides can be a complex matter; it depends on brands of film, on previous storage of the slides, and on type of mount (what kind of frame they've been mounted in), and possibly other factors too.

I've repaired several slides similar to the one you shared, guess this one is an AGFA-GEVAERT positive film, possibly a FUJIFILM. Sometimes a generic automatic filter like "Equalize" will do the trick; problem is that often a great deal of image info will be lost. Other problem is that usually not all the original photos were ever "correctly" exposed.
Existential problem; do you want to be faithful to the original images or just get decent usable photos right away?

I searched the web thoroughly for info on how to do this with FOSS-software; there are some scripts (mostly for GIMP) for certain types of film of certain age (yes, the year of production counts), but the majority of those doing such work resort to using the commercial extensions available for Photoshop. Those are sort of databases with measured decay of various types of film, along with commands for corresponding filters.

Nevertheless I found a neat procedure for doing this in GIMP (can't find the source right now); Take one of a batch similar slides (from one shooting, one year or similar exposure), demount it from the plastic frame (bad luck if it's glued into a paper frame) and scan the whole area, including the perforated strip on both sides, where normally there should be markings in clear letters with the brand name and number of the image.

In "Levels" histogram mode with the eyedropper-tool in "All channels" section, change the white-point to a decent sample of a letter on the strip (transparent = white), similarly take the black-point from the surrounding black/opaque frame, then pick a gray-point (where a gray area should be) from the image itself. This way you're compensating for the "natural" decay of the corresponding film (of a certain brand, certain age). You may then have to fiddle with all the color-components separately to further enhance colors. The most important is to save the result as a preset, and then use that preset manually on each image (with further enhancements like sharpening etc.) or use it on several images with GIMP --headless on the command line.

You could also use the values from this preset to make settings for the BatchQueue Manager in Digikam or some script for ImageMagick.

But as stated above, this procedure only compensates for the natural decay of the film itself, not the decoloration of the image due to sunlight or overuse (number of passages in a projector).

For those who like the technical side of things: <http://www.lionhouse.plus.com/photorestore/Restore2.pdf>

Good luck,

Just some thoughts - good luck restoring your slides,
Sveinn í Felli

On 12/05/2021 11:50, Gilles Caulier wrote:

Le mer. 12 mai 2021 à 04:39, Errol Sapir <[hidden email] [hidden email]> a écrit :

    Hi All

    I am now trying Manjaro KDE after many years of Kununtu. Of course I am
    also planning to transfer (or redo) my Digikam from Kubuntu to Manjaro. I
    have however a photo question that doesn't specifically apply specifically
    to either of these programs. As I said in the subject I hope it isn't OT
    but as it is photo connected and I hope Digikam can help as well I would
    appreciate the help of anyone who can. If it is OT the moderators can
    remove my post and I will understand.

    I am transferring all my slides (and eventually negatives) to digital
    format. I am looking for a one-click solution (program) that will restore
    colours back to normal.



You want mean to invert color ? If yes, ImageMagick is your friend, especially -negate option:

https://superuser.com/questions/1194468/invert-colors-with-imagemagick

This can be scripted of course to parse and process automatically all files from your collection. And of course, all can be done de facto under Linux from command line.

Else, In digiKam, Invert Color tool from Batch Queue Manager can be used. Create a new Queue, assign items to process, configure the output options (path, file name, etc...), assign Invert tool + the convert format if necessary, and... you can take a coffee.

Best

Gilles Caulier

[Errol Sapir]

Hi Sveinn

I tried your suggestion on one photo and think this is a good solution which I will adopt and try and modify for my needs. I attached a link to the original photo and one to the repair I did using your method without any further attempts to tweak or improve the photo. The recovered colours are a good start to retrieving the colours in old slides I digitized.

Thank you

Errol

old photo

https://mega.nz/file/QxlEAIbI#gwt5Omb5cSa1-WPeDxVlTdtyoNkwZYdeUC9xVp9L6b4

corrected photo

https://mega.nz/file/E4U3nYza#D0Q9wgxmbNb2j5ou2kg74ETedTwcGeQyAPFisSwdz8U

On 19/05/2021 15:48, Errol Sapir wrote:

Hi Sveinn

Thank you for your detailed explanation and link to the technical explanation. If I understand your solution seems to be in Gimp. I will try and apply some of your methods and see where it takes me. My main aim is to get decent usable photos right away with the option of further tweaking the better ones after restoration. I will report back here results. Meanwhile if there are any further suggestions I would appreciate them.

TIA

Errol

On 17/05/2021 14:57, Sveinn í Felli wrote:

Þann 12.5.2021 17:48, skrifaði Errol Sapir

Hi Gilles

The idea isn't to invert colour but to enhance colour. The slides have faded and
the original colours aren't alive. The link shows a photo that has faded.

Errol

https://mega.nz/file/QxlEAIbI#gwt5Omb5cSa1-WPeDxVlTdtyoNkwZYdeUC9xVp9L6b4

Hi Errol,

Scanning and repairing old slides can be a complex matter; it depends on brands of film, on previous storage of the slides, and on type of mount (what kind of frame they've been mounted in), and possibly other factors too.

I've repaired several slides similar to the one you shared, guess this one is an AGFA-GEVAERT positive film, possibly a FUJIFILM. Sometimes a generic automatic filter like "Equalize" will do the trick; problem is that often a great deal of image info will be lost. Other problem is that usually not all the original photos were ever "correctly" exposed.
Existential problem; do you want to be faithful to the original images or just get decent usable photos right away?

I searched the web thoroughly for info on how to do this with FOSS-software; there are some scripts (mostly for GIMP) for certain types of film of certain age (yes, the year of production counts), but the majority of those doing such work resort to using the commercial extensions available for Photoshop. Those are sort of databases with measured decay of various types of film, along with commands for corresponding filters.

Nevertheless I found a neat procedure for doing this in GIMP (can't find the source right now); Take one of a batch similar slides (from one shooting, one year or similar exposure), demount it from the plastic frame (bad luck if it's glued into a paper frame) and scan the whole area, including the perforated strip on both sides, where normally there should be markings in clear letters with the brand name and number of the image.

In "Levels" histogram mode with the eyedropper-tool in "All channels" section, change the white-point to a decent sample of a letter on the strip (transparent = white), similarly take the black-point from the surrounding black/opaque frame, then pick a gray-point (where a gray area should be) from the image itself. This way you're compensating for the "natural" decay of the corresponding film (of a certain brand, certain age). You may then have to fiddle with all the color-components separately to further enhance colors. The most important is to save the result as a preset, and then use that preset manually on each image (with further enhancements like sharpening etc.) or use it on several images with GIMP --headless on the command line.

You could also use the values from this preset to make settings for the BatchQueue Manager in Digikam or some script for ImageMagick.

But as stated above, this procedure only compensates for the natural decay of the film itself, not the decoloration of the image due to sunlight or overuse (number of passages in a projector).

For those who like the technical side of things: <http://www.lionhouse.plus.com/photorestore/Restore2.pdf>

Good luck,

Just some thoughts - good luck restoring your slides,
Sveinn í Felli

On 12/05/2021 11:50, Gilles Caulier wrote:

Le mer. 12 mai 2021 à 04:39, Errol Sapir <[hidden email] [hidden email]> a écrit :

    Hi All

    I am now trying Manjaro KDE after many years of Kununtu. Of course I am
    also planning to transfer (or redo) my Digikam from Kubuntu to Manjaro. I
    have however a photo question that doesn't specifically apply specifically
    to either of these programs. As I said in the subject I hope it isn't OT
    but as it is photo connected and I hope Digikam can help as well I would
    appreciate the help of anyone who can. If it is OT the moderators can
    remove my post and I will understand.

    I am transferring all my slides (and eventually negatives) to digital
    format. I am looking for a one-click solution (program) that will restore
    colours back to normal.



You want mean to invert color ? If yes, ImageMagick is your friend, especially -negate option:

https://superuser.com/questions/1194468/invert-colors-with-imagemagick

This can be scripted of course to parse and process automatically all files from your collection. And of course, all can be done de facto under Linux from command line.

Else, In digiKam, Invert Color tool from Batch Queue Manager can be used. Create a new Queue, assign items to process, configure the output options (path, file name, etc...), assign Invert tool + the convert format if necessary, and... you can take a coffee.

Best

Gilles Caulier