19.1 problems with transparency

To cut out a part of a clip and use it as an overlay I used a polygon on the MediaIn node. The background is shown as transparent on MediaOut node:

Fusion Trans 01.png (416.97 KiB) Viewed 732 times

on the edit page the background is black, no transparency

Fusion Trans 02.png (471.99 KiB) Viewed 732 times

In your example you seem to have some keyframes on the jpeg you are masking and some FX applied to it. What kind of FX did you apply and what did you animate? That could be causing the black background.


Since version 19 we can choose checkboard pattern for transparency on the edit page, same as in fusion, but not on other pages, which needs to be addressed. However you can change how the transparency shows in the timeline options. Keep in mind that fusion by default references the clip on timeline, but sources is from media pool, which may result in different source resolution. If timeline and original clip are not of the same resolution. If that happens, and you are not sure how fusion deals with resolution and media, reference the manual for more details.

Hi Kruno,
thanks for your reply.

In the Fusion Comp there is no animation, it is just the polygon selection and the transform to shrink and move it e little bit (static).
In Fusion the background is shown transparent and in the edit Page it is not, no matter what timeline view option is chosen.

To demonstrate this I placed the Fusion clip above another clip which should then shine through, but it doesn't as shown in picture 2

Actually, I was referring to this icon.... indicating there is some kind of FX applied to it in the edit page or somewhere outside of fusion. What is it?

sshot-1130.jpg (100.83 KiB) Viewed 378 times

Okay, this was a Drop Shadow but it makes no difference after removing it:

Fusion Trans 03.png (514.53 KiB) Viewed 362 times

Don't you need to merge the output of the transform over a transparent background node? That's how I usually do this kind of thing

Hey Kruno,
thanks again for your research. Here is the solution.

• the Drop Shadow was applied to the image because I first wanted to use it as whole just at a smaller size.
• then I decided to use it as a mask with fusion and the shadow was still applied as an effect to the clip
• the deletion of the shadow effect didn't work (Bug?)
• take a fresh image from the Media Pool create the mask and everything works as expected.
• afterwords the Drop Shadow can be applied again and it works fine

Fusion Trans 07.png (624.59 KiB) Viewed 349 times

Oh, I see. Could be related to caching issues. Some people report various issues that I would put mostly in the caching category. So maybe that was the issue here. I tried to replicate what you wrote, but couldn't get the same behaviour. On my machine it seems to work as one would expect. Well, at least you sort it out. That's good.

Thanks again guys for your efforts