Why does my product logo cover the entire frame after I connect it to a Fusion Merge node?

Identify which input owns the product video

Blackmagic Design's Fusion documentation identifies the Merge node's yellow input as the background and its green input as the foreground. The foreground is composited over the background using its alpha information and the selected operation.

For a straightforward product-logo overlay, the video normally supplies the background image and the logo supplies the foreground image. A reversed connection can produce a different composite, but correct wiring alone does not guarantee a visible product.

Load each input into a viewer independently. Confirm that the background is the intended product frame. Confirm that the foreground contains the intended logo and inspect whether its surrounding pixels are transparent or opaque.

A white rectangle surrounding a black logo is not necessarily transparency. If the rectangle has full alpha, the foreground can cover the entire frame even when the logo itself occupies only a small portion of the picture.

Do not assume a PNG filename proves that an alpha channel exists. PNG supports transparency, but an individual PNG can be fully opaque.

Use a minimal Merge comparison

Preserve the production composition and create a simple diagnostic branch containing the product background, one logo foreground and a Merge node.

1. Connect the product image to the documented background input.
2. Connect the logo to the foreground input.
3. Inspect the foreground alpha independently from its RGB appearance.
4. Compare a known transparent logo with an opaque full-frame version.
5. Inspect the merged result before adding tracking, animation or other effects.

If the transparent source reveals the product while the opaque version covers it, the relevant difference is the foreground's coverage. The next step is to prepare or select the correct alpha-bearing logo asset in an external graphics editor.

If both versions behave unexpectedly, inspect the Merge operation, channel settings and upstream processing. A mask, background generator or channel operation can change the foreground's alpha before it reaches Merge.

Blackmagic's Fusion tool reference documents compositing modes beyond ordinary foreground-over-background behavior. Avoid treating every Merge configuration as the same operation.

Hypothetical example: a white logo canvas hides a speaker

Hypothetical example; no Fusion node graph was executed. A fictional speaker advertisement needs a small charcoal logo in the upper-right corner.

Candidate A uses a full-frame white image containing the charcoal mark. The entire image is stipulated to have full opacity. Connected as the foreground, it covers the speaker footage.

Candidate B uses the same mark with transparent pixels outside the logo. In the proposed ordinary-over composite, the speaker should remain visible outside the logo's occupied area.

Candidate C uses the transparent asset but connects the product video to the foreground and the logo to the background. The result no longer represents the intended simple overlay structure.

B is the preferred source-and-connection combination for this hypothetical case. The exact appearance still depends on the actual node settings and source alpha.

The example is not a claim that changing a connection automatically converts an opaque asset into a transparent one.

Review the logo after the composite is correct

Once the product footage remains visible, check the logo's approved color, edge quality, scale and placement. Review the overlay at entry, full visibility and exit if it animates.

If the logo has dark or light fringes, inspect its alpha interpretation and source pixels separately. A premultiplication mismatch is a different mechanism from an opaque foreground rectangle.

Check whether the logo covers essential product information or conflicts with destination controls. The correct node graph can still produce a poor advertising composition.

Retain the original asset, corrected alpha-bearing copy, Fusion graph version and exported result. Do not flatten the only editable brand master merely to make one video overlay work.

CartVisual-generated logo concepts are not automatically production-ready vector or transparent assets. The required alpha preparation and Fusion compositing take place in the relevant external applications.

Approval requires the delivered video to preserve both the merchandise and the approved logo treatment. A successful Merge connection is only the technical starting point.

Record your own observations

The filled rows are illustrative examples. Use the blank row for your own files and observations.

Download the editable CSV worksheet

What the references establish

• Blackmagic Design — DaVinci Resolve Fusion: Documents the Merge node's yellow background and green foreground connections and the basic compositing workflow.
• Blackmagic Design — Fusion Tool Reference, Merge: Direct description of foreground alpha, background/foreground roles and compositing operations. Historical manual; current controls should be checked.