where to find blue channel script

[denzjos]

Anyone knows where to find this script : https://patdavid.net/2013/04/getting-aro...e-channel/
The link that is mentioned give error 404, script not available.
If someone find a working link, thanks in advance.

[rich2005]

You can get from the internet achive and depending on date, a version 1 (patdavid - check layer_0.scm) and a version 2 (patdavid - check layer.scm) 

To save internet archive bandwidth, both attached + a pdf dump of the webpage.

[denzjos]

Thanks rich for the reply. I'll try them out.

[Ofnuts]

Hardcore way: Go to the Gimp registry, saved on GitHub by PatDavid:  here. Click the Raw button, then in your browser File>Save.

Easy way: the internet archive at https://archive.org/index.php . Copy the link from PatDavid's page, and pick one of the snapshots (usually, one of the latest).

[Krikor]

In the video, Pat David uses the Color mode for the white layer. This mode no longer exists in versions 2.10 of Gimp.

In place of the Color mode, would it be correct to use the HSV Saturation mode on the white layer?

[rich2005]

A Gimp 2.8 layer in 'Color' mode opened in Gimp 2.10 translates to Mode HSL Color (I) (legacy mode)  Change that to default mode and that is HSL Color. 

I assume that is correct. A Gimp 2.8 xcf file attached.

[Krikor]

(05-15-2021, 01:49 PM)rich2005 Wrote: A Gimp 2.8 layer in 'Color' mode opened in Gimp 2.10 translates to Mode HSL Color (I) (legacy mode)  Change that to default mode and that is HSL Color. 

I assume that is correct. A Gimp 2.8 xcf file attached.

Hi rich2005, thanks for the feedback.

I also always used HSL Color when following old tutorials that asked for Color mode for a certain layer. But using this mode (HSL Color) on the white layer, following Pat David's tutorials, all that becomes visible is a black silhouette. 
   
Only with HSV Saturation is it possible to view an unsaturated image. So I was about to assume that this mode would be the correlate to the old Color mode.

[rich2005]

I do not think the procedure as described is valid with Gimp 2.10 Default layer modes.

However, on the basis that the idea is to highlight blemishes so that the base color layer is improved using the heal tool, this is the closest I can get using Gimp 2.10 default layer modes.  It is the (red + green = yellow) layer in Linear burn which makes the difference. Dodge is still dodge, although you can tweak the grey colour . White is HSL color mode.

   

The whole thing is a bit flaky. Best bet use the legacy modes while they still exist.

[Krikor]

(05-15-2021, 03:11 PM)rich2005 Wrote: I do not think the procedure as described is valid with Gimp 2.10 Default layer modes.

However, on the basis that the idea is to highlight blemishes so that the base color layer is improved using the heal tool, this is the closest I can get using Gimp 2.10 default layer modes.  It is the (red + green = yellow) layer in Linear burn which makes the difference. Dodge is still dodge, although you can tweak the grey colour . White is HSL color mode.

The whole thing is a bit flaky. Best bet use the legacy modes while they still exist.

rich2005, as per your post #6 everything led to believe that the replacement mode for the old Color mode would be HSL Color; although this makes the steps in Pat David's tutorial not reproducible in Gimp 2.10. 

About using the Linear Burn mode as an alternative, it seemed to me outside the original idea of the tutorial, which was to subtract the yellow from the image, generating an image similar to the one obtained when working with the blue channel only.

Using the Linear Burn mode instead generated a yellowish image.

I tried working directly with the blue channel, and the result in terms of visualized image was satisfactory, but it was impossible to use the healing brush and see the changes happening at the same time. At this point the blue toned layer was the layer being edited and not the color image.
   

>>What caught my attention was that Color Mode was desaturating the layers below it (the layer in color mode), but with HSL Color mode I was desaturating only the layer below (yellow).<<

So I experimented with working with layer groups and voilà!

Using a layer group, I could use all layers with the expected modes (white layer with HSL Color mode) and practically reproduce Pat David's tutorial.
   
Maybe someone can create a script for Gimp 2.10 based on this presentation of mine.

rich2005, thanks for the help!

[denzjos]

(05-15-2021, 10:45 AM)Ofnuts Wrote: Hardcore way: Go to the Gimp registry, saved on GitHub by PatDavid:  here. Click the Raw button, then in your browser File>Save.

Easy way: the internet archive at https://archive.org/index.php . Copy the link from PatDavid's page, and pick one of the snapshots (usually, one of the latest).

Hardcore way is working (as usual...) but copy the link to the archive wasn't working for me (http://registry.gimp.org/node/28017). I forgot to chose the 'search archived web sites'.
Thanks for the tip Ofnuts.