4 Replies Latest reply on Feb 9, 2010 6:38 PM by reindeer4

    Getting alpha channel to export from AFX to Photoshop

    reindeer4 Level 1

      I have an image in After Effects CS4 with some text on it and a transparent background.  I need to export this as a png (retaining the background transparency).  I've tried to do this in many ways (as single frame or as png sequence after reducing work area to my single frame, and as prematted or straight alpha (both with RGB 16million Plus) . . . but I keep getting a black matte in background.  Tried exporting both as png and as photoshop file.

       

      Can someone explain the correct way of doing this?  (The alpha channel does transfer to photoshop, so if there's a simple way to use that to mask out the background (or mask in the part of the picture I need) I guess that would suffice.  It was just mean I need to make my text brilliant green or something in AFX and then convert to black in photoshop.

       

      Is this some kind of bug or am I just missing the simple way to do this?

       

      Thanks for any help.

        • 1. Re: Getting alpha channel to export from AFX to Photoshop
          Mylenium Most Valuable Participant

          The fault lies with PS. I will not repeat the endless tiring excuses of certain Photoshop engineers, but they think that "a channel is just a channel" and per se "Alpha does not equal transparency". Therefore many image formats require you to manually load the transparency info from a channel. This can be easily done by Ctrl+clicking on the thumbnail in the channels palette after converting the Background layer into a floating layer. You can then simply hit delete to remove the selected parts and get "real" transparency.

           

          Mylenium

          • 2. Re: Getting alpha channel to export from AFX to Photoshop
            reindeer4 Level 1

            Thanks Mylenium.

             

            Can you explainyour method in more detail.

             

            I double clicked the later title to create a floatin layer.

            Then I went into Channels and CTRL clicked no the alpha layer which makes a selection of the correct portions of the image.

             

            Clicking delete (or inverting selection and then clicking delete) doesn't get rid of everything.

             

            Can you spell out what else I have to click on first - do I go back to the regular image in layers and then hit delete or apply my selection as a mask?

             

            I did manage to fumble through things once, but if you don't mind spelling out the right method, I'd like to learn the right way.

             

            Thanks

            • 3. Re: Getting alpha channel to export from AFX to Photoshop
              Mylenium Most Valuable Participant

              Yes, of course, you must select the layer content to delete. deleting pixels in the mask itself will degenerate it and increase contrast. Alternatively, apply the selection as a layer mask. click on cthe respective icon at the bottom of the layers palette or use Selection --> Save Selection, with the destination set to This Document and a new channel (layer mask).

               

              Mylenium

              • 4. Re: Getting alpha channel to export from AFX to Photoshop
                reindeer4 Level 1

                Hey Mylenium,

                 

                Thanks for taking the time to help.