Question about Alpha Masks (Photoshop)

leedeetee · 5 Mar 2012, 23:12

Does anyone know what I'm doing wrong?

I open up my render in Photoshop
I open up my alpha mask in Photoshop
I insert a layer mask onto my render
I alt click onto the layer mask and paste the alpha mask into it
I right click onto the chain and apply the alpha mask
Then, for some reason, my render seems to have reduced in opacity.

Any ideas? I have attached a screenshot.

Cheers!

tadema · 5 Mar 2012, 23:25

Hello Lee,
Place your alpha mask above your image ( file place ), right click to place it. Select/Colour Range (and with the ink dropper select black) Activate your image and delete.
John

leedeetee · 6 Mar 2012, 08:23

Thanks John, that's a really neat workaround.

It is odd though. I've just used exactly the same method as I did originally to mask out some vegetation, and it's worked fine.

I don't like things I don't understand!

Alan Fraser · 6 Mar 2012, 13:13

It may be that the partial transparency value in the window material has led to a partial transparency in the mask in those window areas, when using your original method. It shouldn't do, but that's what appears to have happened. I can't see the checkerboard background showing through the concrete shell.
It's usually fairly easy to firm-up such partially transparent layers in PS...just duplicate them a few times then merge them.

leedeetee · 6 Mar 2012, 15:13

Ah Alan, thanks very much for the reply. That seems to be it. Very succint explanation too, many thanks.