My trouble with basic compositing functions

Silhouette can make hard stuff look trivial, but sometimes I find doing trivial functions to be a mystery.
(I come from AE/Blender compositors)

I’m going to post a simple insert and show the troubles I’m having, I’d like to learn what I’m doing wrong…

1A. How to crop an insert image?
If I use crop node on an insert image (phone screen) (1B), then resize to HD for the insert (1C), the effect of the crop does not seem to apply… if I adjust the crop node, it adjusts the resize node at the same time?? (this adjusting distorsts and moves the insert around)

  1. Can I set the roto node “surface” to have an alpha that I can pass on downstream? (without a separate roto shape) (1D), (1E)

Continued on next post =>

Because of the crop node, my insert is in the wrong place. (1F)

If I bypass the crop node, then reset the resize node to HD again… (why?)
The insert goes to the correct position.

Why is the no alpha for the insert/surface?

To summarize:
-why can I not crop the image then have the results passed on to the resize node?
(this is equivalent to fit-to-comp in AE… so it will align w mocha surface)

-Why are crop and resize nodes affecting each other up/down stream?
(Do I have to go to photoshop to crop an image??)

-Why do I need to apply 2 composite nodes to get the full size comp back? (1H)

-Why does the surface no have an alpha?
(do I need to do a separate transform on a roto shape just to have an alpha?)

Sorry for all the noob questions, but a lot of functions are so different than AE/Blender.

Any help is much appreciated.
(I will probably have more questions…)

Hi, I’m a novice too so I’m sure we’ll both learn from this :joy:

but have a look at Obey Matte to control the wanted visible area, ,

this was a very loose transform of an image

here i created a Roto spline around the board

& i plugged Roto into the blue port on Transform & told it to Obey Matte

For the misalignment i find in other software such as Mocha it’s because the two bits of Media are different dimensions, whether that’s true in Silhouette, & i think that #s why in AE they precompose media, but not having AE i don’t know,

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Your example makes sense, but…
When I do it, it does not work.
(I have purged ram)

My source image had no fill in the alpha? (default behavior for some reason)
So, by wiring it differently, i’ve managed to make the comp work.

I don’t understand what the crop node is for if I cant crop footage with it, how do I make the crop function stick?


Your example (1d and 1e) exposes an issue with the Composite node’s matte input. We will fix that now. As you have discovered, if you use the Obey Matte input of the Composite node, you will get the result you are looking for.

Sources may or may not have alpha. If they don’t have alpha initially, they will have alpha after applying the Transform node.

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Thanks Marco,
If I have a square portrait that I want to put on a tall phone screen, how do I nondestructively crop the image before resizing to HD for the surface insert?
(to achieve proper pixel ratio on phone composite … not squished lady like my example.)

I know I could do it in photoshop, but I’m trying to learn the silhouette program top to bottom. :slight_smile:

Have you tried using a DOD set to the Session size instead of the resize. Until the point release comes out, you need to explicitly set the width and height in the DOD. Also, you will need to do some resizing in the Transform node to fit it into the insert.

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This worked, but I had to add another transfer node before the DOD to do the scaling/aspect ratio

thanks again Marco and Gid.Joiner :+1:

A number of DOD and Insert issues were addressed in Silhouette 2022.0.3 available here:

You no longer have to add Resize and DOD nodes after images smaller than the session when doing an insert. Also, using Sapphire nodes with images smaller than the session also now works as expected. If you have a project with an insert created with Silhouette 2022.0-2022.0.2, you may have to reposition the insert.