5

I've searched high and low and finally hit upon alpha channels, but I don't know how to configure an alpha channel to suit my needs. I'm trying take this image...

before

...And turn it into this. As you can see the top portion is 100% opaque, and the bottom is 0%. So its a kind of "alpha mask". How can I do this with Photoshop or Gimp or whatever, and save it into a 32-bit PNG?

result

I'm not simply trying to "cover" or "mask" my image like this question. I'm trying an alpha mask which is a whole different ballgame.

Improve this question
2
  • 1
    @AndrewH - Its NOT a duplicate. That question simply covers the image with a transparent gradient. My question is how to generate a transparent image, an "alpha mask" if you will.
    – Robin Rodricks
    Jan 7, 2016 at 9:38
  • No Geotarget it indeed does exactly what you ask. It is a alpha mask. The demo image just has a black background so you think its a gradient with alpha. Please read again. If the last layer wouldnt be black it would do exactly what you ask.
    – joojaa
    Jan 10, 2016 at 23:41

1 Answer 1

Reset to default
6

You can use clipping masks to achieve this effect!!

  1. Create 2 layers in photoshop
  2. In the 1st layer place your image content
  3. Click the 2nd layer
  4. Select White as the foreground & background color (by clicking the color swatches on the toolbar)
  5. Click the gradient tool, and choose the "opaque to transparent" gradient (the 2nd gradient in the palette)

step

6. Draw a gradient on the 2nd layer

enter image description here

7. Right-click the 1st layer and choose "Create Clipping Mask"

enter image description here

8. Done!

enter image description here

Improve this answer
2
  • This doesn't actually work with the example image in your original post. You should basically do the same thing, but with Layer mask instead of a Clipping mask.
    – Joonas
    Dec 6, 2015 at 17:57
  • While I agree a layer mask would be better, why wouldn't a clipping mask work for the original image?
    – Hanna
    Jan 5, 2016 at 18:46

Not the answer you're looking for? Browse other questions tagged or ask your own question.