Gradient creation

[Antonio Lambe]

Apologies if this question has already been submitted.  In a rectangle, or, better, a polygon at the top of a dawn photo for the portal of a website I want to implement a lightening gradient to set off the site's logo.  Any fool-proof instructions for how to accomplish this will be deeply appreciated.  Thank you.

[frio]

Make a black & white gradient-filled shape on a separate layer and set the layer blend mode to Additive, Color Dodge, Lighten or Screen to create a lightening effect.

 

To make a basic linear or radial gradient in a shape, use the gradient tool to draw the desired gradient and then select the shape you want on it, invert the selection and delete the parts outside. A simple linear gradient cut to an angled rectangle in color dodge mode:

 

 

To create a gradient conforming to a shape specifically, you could try TR's Contour Filler (simple, not so accurate) or G'MIC Rendering->Gradient (custom shape) (more complex, more accurate). Star shapes filled with G'MIC, original on top left, other blend modes in the order mentioned above.

 

 

[Antonio Lambe]

Many thanks, Frio, for the prompt and promising reply.  But you have generously assumed I know a lot more than I do.  I presume one must first go to Layers > Add New Layer which I have apparently done.  To "Make a black & white gradient-filled shape on [this] separate layer" must I then use the Rectangle Select or Lasso Select tool?  Below is the result although the lasso seems to have disappeared.

 

As for the further instructions, I'm afraid that without step-by-step novice instructions I haven't a clue how to proceed.  And perhaps this is too much to hope for.

 

 

[Antonio Lambe]

My efforts with Paint.Net, below, to lighten the sky have proved very clumsy and the transition looks so artificial.  Any simple pointers for achieving that effect would be much appreciated.  Thank you.

 

[Tactilis]

@Antonio Lambe it would make it easier for people help you if you posted:

 

1. The image of your logo.

2. A version of your original photo with the logo overlaid so we can see the size and positioning you are aiming for. Don't worry about the gradient at this stage.

[Welsh Yellow Cheddar]

 

@Antonio Lambe There are probably many methods of achieving this. I would just reduce the opacity of your image and add a white layer below it. To keep the dark trees I would create a mask and place it at the top. You can also tint the sky with a color gradient of your choice on a layer with multiply mode.

 

I hope this helps.

 

[Ego Eram Reputo]

19 hours ago, Antonio Lambe said:

My efforts with Paint.Net, below, to lighten the sky have proved very clumsy and the transition looks so artificial.  Any simple pointers for achieving that effect would be much appreciated.  Thank you.

 

1. Open the image
2. Activate the Magic Wand tool
3. Hold down the Ctrl key and click once on the very dark foreground trees. This should select all of the trees in one go.
4. Press Ctrl + I to invert the selection.
5. Press Ctrl + Shift + U to open the Hue/Saturation dialog.
6. Increase the Lightness slider to lighten the sky to your liking.