Alpha Channel not working

Aerowings · **Joined:** Mar 06, 2021 **Posts:** 4

Hi,
i´ve got a picture (png). If i add a Alpha channel the whole picture dissappears and i only see the grey alpha pattern.

Normally the picture stays and i can edit it.

Whats the problem?

racer-x · **Joined:** Apr 15, 2017 **Posts:** 1837

Click Image > Mode, then make sure it says RGB. See if that changes anything.

Aerowings · **Joined:** Mar 06, 2021 **Posts:** 4

racer-x wrote:

Click Image > Mode, then make sure it says RGB. See if that changes anything.

It is on RGB.
I discovered i can add an alpha channel if i edit just something in the picture.
But i want to add the channel before editing to have the alpha background.

ofnuts · **Joined:** Oct 25, 2010 **Posts:** 4812

Aerowings wrote:

racer-x wrote:

Click Image > Mode, then make sure it says RGB. See if that changes anything.

It is on RGB.
I discovered i can add an alpha channel if i edit just something in the picture.
But i want to add the channel before editing to have the alpha background.

Are we talking about an alpha channel or a layer mask? If a layer mask, don't initialize to black.

Blighty II · **Joined:** Sep 23, 2016 **Posts:** 317

Aerowings wrote:

Hi,
i´ve got a picture (png). If i add a Alpha channel the whole picture dissappears and i only see the grey alpha pattern.

Not enough info there to tell where the problem is.

List all the steps you are doing and the tool/menu used.
At what stage does the picture disappear?

Aerowings · **Joined:** Mar 06, 2021 **Posts:** 4

I want to add a layer mask. Alpha channel. After i press add (hinzufügen) the picture disappears and i just see the alpha squares.

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Konstantin · **Joined:** Sep 20, 2016 **Posts:** 293

Its because you added a layermask and not an alphachannel.
Your screenshot shows clearly you are using the layermask dialogue (Ebenenmaske).

It shows as transparency because the layermask is black.
Either you invert the existing black mask or delete it and choose the white layermask next time.

sallyanne · **Posted:** Sun Mar 07, 2021 1:49 am **(#8)**

Bit more inforamation would help - including OS and gimp version.

Looks like your image is still there and it is just 'masked-out' by the alpha channel mask. Once you use your white brush it will come back.