Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Brighten Portion of Image?
#1
Can't figure out what I'm doing wrong.  Trying to lighten the face of the girl in the attached.  Steps I took:
Duplicate layer.
Use ellipse tool to select face.
Adjust selection as needed (see attached - overbrightened for emphasis).
Use eraser tool - fuzzy brush at 30% or so opacity - to get rid of line between adjusted and non-adjusted part.  Here is where I get unintended results.  Why is the eraser making a white path?  Shouldn't it fill the erased part with the full image underneath?

What am I going wrong?

Thanks!


Attached Files Thumbnail(s)
       
Reply
#2
Simply you omitted this step:
- on the dupicated layer: Layer/Transparency/Add Alpha Channel

Try
Reply
#3
For that image, I would try:

Add a white layer on top
Put that layer into overlay mode
Add a black layer mask: Layer -> Mask -> Add Layer Mask and choose Black (full transparency)
It should look like this: http://i.imgur.com/tfbNujU.jpg same as the original.

Click in the layer mask (the black square) to make it active, it is active if it has that white border.
Change the foreground colour to white, choose the most fuzzy brush you have (probably the one shown in the screenshot)
With a large size, just click once over the head, add a couple more clicks as required.
something like this: http://i.imgur.com/bbUNwxN.jpg

When you screw it up, just fill the layer mask with black and start again Wink
Reply
#4
Because when there is no alpha channel, erasing is like painting with white?

What you really want to do is

  1. add an alpha channel to the top layer:Layer>Tranparecency>Add alpha channel (so this layer can be transparent)
  2. to be able to tweak the opacity, add a "Layer mask"; Layer>Mask>Add layer mask. In the layers list the mask preview appears near the layer preview. you can select if your tools apply to the mayer or to the mask by clicking on the adequate preview. The status bar (bottom of image) tells you if you edit the layer (say "layer_name") or the mask ("layer_name mask")
  3. now you can "paint" the opacity on the mask, what is black is transparent, what is white is opaque. In your case you'll use a soft brush so that it produces grays on its edges. You can correct errors by painting in the opposite color...
  4. when happy with the result: Layer>Mask>Apply layer mask.
Reply
#5
Thank you all for the prompt and detailed replies! Will try these and report back. Not quite sure I understand the concept of adding an alpha channel but will give it a whirl. I appreciate the help.
Reply
#6
(08-12-2017, 02:27 PM)tspence Wrote: Not quite sure I understand the concept of adding an alpha channel but will give it a whirl.
With out alpha channel, an image has just three channels : R, G, B. The values of these channels for a given pixel tell how red/green/blue it is. With an alpha channel (noted 'A'), the image has four channels (R,G,B,A). The value of the 'A' channel for a pixel tells how opaque it is.
Reply
#7
(08-12-2017, 04:41 PM)Ofnuts Wrote:
(08-12-2017, 02:27 PM)tspence Wrote: Not quite sure I understand the concept of adding an alpha channel but will give it a whirl.
With out alpha channel, an image has just three channels : R, G, B. The values of these channels for a given pixel tell how red/green/blue it is. With an alpha channel (noted 'A'), the image has four channels (R,G,B,A). The value of the 'A' channel for a pixel tells how opaque it is.

Gotcha - thanks!
Reply


Forum Jump: