How to use the Alpha Mask / Alpha Channel

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alvydas
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Re: How to use the Alpha Mask / Alpha Channel

Post by alvydas » Mon Mar 01, 2021 3:49 pm

i can show. it's very simple :D

ntxdave
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Re: How to use the Alpha Mask / Alpha Channel

Post by ntxdave » Mon Mar 01, 2021 4:45 pm

Well, I do have a couple more (better I think) images that I created with GIMP in this tread.

I am sure open to learning though if there is something you would like to share. :)

ntxdave
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Re: How to use the Alpha Mask / Alpha Channel

Post by ntxdave » Mon Mar 01, 2021 10:28 pm

OK, I figured/found out you can also use the Alpha Mask with Inkscape. Since Inkscape is a vector tool and GIMP is a raster tool, GIMP maybe better in some cases. Here is a comparison below:
Inkscape example
Inkscape example
InkscapeBlowerDryer.png (434.43 KiB) Viewed 1739 times
GIMP example
GIMP example
AlphaMaskingTest.png (229.63 KiB) Viewed 1739 times

alvydas
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Re: How to use the Alpha Mask / Alpha Channel

Post by alvydas » Tue Mar 02, 2021 10:55 pm

ntxdave wrote: Mon Mar 01, 2021 4:45 pm Well, I do have a couple more (better I think) images that I created with GIMP in this tread.

I am sure open to learning though if there is something you would like to share. :)
https://www.dropbox.com/s/ltiytqmt9nksr ... p.wmv?dl=0 Easy video instruction
Toy+Ford+Woody+Wagon_Scene 1final.zip
(1.38 MiB) Downloaded 58 times
here simple channel tree . Xcf format. Just open it direct in Gimp
Attachments
Toy+Ford+Woody+Wagon_Scene 1final.png
Toy+Ford+Woody+Wagon_Scene 1final.png (748.68 KiB) Viewed 1734 times

ntxdave
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Re: How to use the Alpha Mask / Alpha Channel

Post by ntxdave » Wed Mar 03, 2021 12:23 am

Thanks for sharing. I will look at it (probably tomorrow). EDIT: Is there a way for me to download the movie?

I did watch a GIMP video that taught me a lot. I am working on another on another GIMP image using several of the features I saw in the video just to understand how to use them. It will not be as clean and neat as the model you shared but my goal is, as I said, to learn how to take advantage of some of the features in the video. So the result will not be as professional looking but as I said, the emphasis is learning how to take advantage of some of the tools. Hope to be able to share it soon.

Again, that for sharing the useful information. :hat:

alvydas
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Re: How to use the Alpha Mask / Alpha Channel

Post by alvydas » Wed Mar 03, 2021 5:00 am

ntxdave wrote: Wed Mar 03, 2021 12:23 am Thanks for sharing. I will look at it (probably tomorrow). EDIT: Is there a way for me to download the movie?
at the top right corner is a link to download
Attachments
Screenshot_20210303-065716~2.png
Screenshot_20210303-065716~2.png (90.78 KiB) Viewed 1722 times

ntxdave
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Re: How to use the Alpha Mask / Alpha Channel

Post by ntxdave » Wed Mar 03, 2021 5:57 pm

DUH - I should have caught that one..........downloaded and watched. See that you did a couple of things differently than I did so got to go off any play around some more........and learn................. :wall: I also love the shadow technique you used. It is pretty neat. :whoot:

There is another video that I am using as a reference as well that has some good tips even though it is just a starter. Check out this starter video

If there are others you would suggest, I would love to know them. I am thinking that Twilight and GIMP is a pretty good combination. :)

Hopefully I can get a new image created today.

ntxdave
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Re: How to use the Alpha Mask / Alpha Channel

Post by ntxdave » Wed Mar 03, 2021 11:20 pm

Well, after a bunch of stupid mistakes, I finally have an image that incorporates the alpha channel along with some other GIMP features. While I still have a lot to learn, I am beginning to understand the program and how it can be used with Twilight Render to accomplish some sophisticated stuff. I appreciate the guidance you guys have given me.
MaskedBlower_MaskedRender_Presentation.png
MaskedBlower_MaskedRender_Presentation.png (2.21 MiB) Viewed 1702 times

Fletch
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Re: How to use the Alpha Mask / Alpha Channel

Post by Fletch » Thu Mar 04, 2021 7:00 pm

ntxdave wrote: Wed Mar 03, 2021 11:20 pm I appreciate the guidance you guys have given me.
:hat:

ntxdave
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Re: How to use the Alpha Mask / Alpha Channel

Post by ntxdave » Thu Mar 04, 2021 9:12 pm

Well, I found out how to do this with Xara Photo & Graphic Designer. Here is the result.
MammorthBlower_MaskedPresentation_Xara.png
MammorthBlower_MaskedPresentation_Xara.png (1.45 MiB) Viewed 1685 times
The steps are pretty easy and very similar to what Fletch showed for the GIMP process.
  1. Place the rendered image that is to be masked in Xara
  2. Place the alpha mask in Xara
  3. Adjust the size of the mask to match the size of the rendered image
  4. Crtl-C the mask
  5. Right click the rendered image and then select the Past as Opacity Mask
  6. Now you can delete the mask image
You can then use any of the Xara tools to edit the final image any way you want to including background images and etc. :whoot:

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