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Plugin for special black-level to apply at greater levels - Printable Version

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+--- Thread: Plugin for special black-level to apply at greater levels (/Thread-Plugin-for-special-black-level-to-apply-at-greater-levels)



Plugin for special black-level to apply at greater levels - robertkjr3d - 03-18-2024

I really can see use of the in the case of planetary objects such as the Moon/Sun. "Astrophotography" shots.  Where the pattern of the light is brighter on the outer-edge of the disc (maybe) and you might want to apply a black-level from the outer edge inward at greater levels..... Or visa-versa (depending on the shot.)  It would be nice to have control like that. 

Some anti-vignetting tools give some control to apply similar controls to what I'm talking about.  But a custom Black-Level tool if someone knew how to create one would be cool.  Or 'Contrast-Apply' tool.

sometimes if I'm doing a half-moon, it may not be a perfect circle.  so it should work with the box-select and/or free-select tool.
or if you can think of another solution.  

Obviously I get by with 'Levels', 'Curves' and Balancing the 'Shadows-Highlights' screens.


RE: Plugin for special black-level to apply at greater levels - PixLab - 03-18-2024

(03-18-2024, 12:17 PM)robertkjr3d Wrote: I really can see use of the in the case of planetary objects such as the Moon/Sun. "Astrophotography" shots.  Where the pattern of the light is brighter on the outer-edge of the disc (maybe) and you might want to apply a black-level from the outer edge inward at greater levels..... Or visa-versa (depending on the shot.)  It would be nice to have control like that. 

Some anti-vignetting tools give some control to apply similar controls to what I'm talking about.  But a custom Black-Level tool if someone knew how to create one would be cool.  Or 'Contrast-Apply' tool.

sometimes if I'm doing a half-moon, it may not be a perfect circle.  so it should work with the box-select and/or free-select tool.
or if you can think of another solution.  

Obviously I get by with 'Levels', 'Curves' and Balancing the 'Shadows-Highlights' screens.

Top GIMP menu Colors ➤ Exposure... You have the black "black-level"

[attachment=11488]


RE: Plugin for special black-level to apply at greater levels - robertkjr3d - 03-18-2024

I use the 'Exposure-->Black-Level' window all the time. I guess I never understood 'Blending Options'. Your saying if I change 'Opacity': I will have some options for what I was talking about?


RE: Plugin for special black-level to apply at greater levels - PixLab - 03-18-2024

(03-18-2024, 02:32 PM)robertkjr3d Wrote: Your saying if I change 'Opacity': I will have some options for what I was talking about?

No, no no, read my comment ➤ I did not say anything, i just told you where you can find "a" black-level as your comment, not even sure about what you are asking, now having and exert of your image and what you are searching for, would help us help you more in a straight forward way Wink


RE: Plugin for special black-level to apply at greater levels - rich2005 - 03-18-2024

(03-18-2024, 12:17 PM)robertkjr3d Wrote: ...snip.....
Some anti-vignetting tools give some control to apply similar controls to what I'm talking about.  But a custom Black-Level tool if someone knew how to create one would be cool.  Or 'Contrast-Apply' tool.
.......
Obviously I get by with 'Levels', 'Curves' and Balancing the 'Shadows-Highlights' screens.

Maybe the gimp_gmic_qt  plugin from http://www.gmic.eu - the zones filter.

[attachment=11490]

The original inset for reference.


RE: Plugin for special black-level to apply at greater levels - Ofnuts - 03-18-2024

(03-18-2024, 12:17 PM)robertkjr3d Wrote: I really can see use of the in the case of planetary objects such as the Moon/Sun. "Astrophotography" shots.  Where the pattern of the light is brighter on the outer-edge of the disc (maybe) and you might want to apply a black-level from the outer edge inward at greater levels..... Or visa-versa (depending on the shot.)  It would be nice to have control like that. 

Some anti-vignetting tools give some control to apply similar controls to what I'm talking about.  But a custom Black-Level tool if someone knew how to create one would be cool.  Or 'Contrast-Apply' tool.

sometimes if I'm doing a half-moon, it may not be a perfect circle.  so it should work with the box-select and/or free-select tool.
or if you can think of another solution.  

Obviously I get by with 'Levels', 'Curves' and Balancing the 'Shadows-Highlights' screens.
  • Create a circular selection
  • Add a layer, set to Multiply mode (other modes such as Screen can also do the job)
  • Fill with black-to-white (or white-to-black)  radial gradient, and while in the gradient tool:
    • You can change the opacity of the layer to adjust the "strength"
    • You can change the layer blend mode
    • Hover need the middle of the gradient (this makes the midpoint appear) and click on it. You can then:
      • Drag the midpoint to change the gradient progression
      • Change the blend function in the on-canvas dialog
[attachment=11491]



RE: Plugin for special black-level to apply at greater levels - robertkjr3d - 03-19-2024

[quote pid='38500' dateline='1710785487']
  • Create a circular selection
  • Add a layer, set to Multiply mode (other modes such as Screen can also do the job)
  • Fill with black-to-white (or white-to-black)  radial gradient, and while in the gradient tool:
    • You can change the opacity of the layer to adjust the "strength"
    • You can change the layer blend mode
    • Hover need the middle of the gradient (this makes the midpoint appear) and click on it. You can then:
      • Drag the midpoint to change the gradient progression
      • Change the blend function in the on-canvas dialog
[/quote]
I love this, it seems complicated, but I'll try it.