Render Target exports as fully transparent PNG regardless of material or texture settings

General Issues and Bug Reporting
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Summary

I’m rendering an unlit material to a Render Target 2D and attempting to export it as a PNG, but the exported file is always fully transparent (0 alpha on every pixel) even though the material renders correctly and is visible in the Content Browser thumbnail.

Please select what you are reporting on:

Creative

What Type of Bug are you experiencing?

Other

Steps to Reproduce

Setup:

  • Render Target 2D format: RTF_RGBA8_SRGB
  • Target Gamma: 2.2
  • Material Blend Mode: AlphaComposite (Premultiplied Alpha)
  • Material Shading Model: Unlit
  • Opacity pin: Constant 1.0
  • Emissive Color: material output

Blueprint sequence:
Draw Material to Render Target → Delay (1.0s) → Export Render Target

What I’ve tried:

  1. Using the Export Render Target node — exports a PNG that is fully transparent (0 alpha on every pixel) despite being 1024x1024 and ~400kb in file size, meaning RGB data is present but alpha is 0
  2. Tried Blend Modes: Translucent (alpha writes at 0.5 opacity but not 1.0 or 0.0, suggesting premultiplied alpha is corrupting the output), AlphaComposite (always exports with 0 alpha)
  3. Created a Static Texture from the Render Target via right-click → Create Static Texture — the Content Browser thumbnail shows the material correctly, but opening the texture shows it as fully transparent
  4. Changing the Static Texture’s Compression Settings to Compress Without Alpha fixes the preview — the texture now displays correctly with proper colors after also enabling sRGB on the texture
  5. However, exporting that Static Texture as PNG via Asset Actions → Export still produces a fully transparent file

Expected Result

What I need:
A way to export the rendered material as a PNG with full opacity (alpha = 1.0 on all pixels), or any reliable method to export a Render Target’s contents to a readable image file with correct RGB values and no transparency.

Observed Result

Fully Transparent PNG export even though the RGB channels are exported correctly.

Platform(s)

Windows 11 64-bit Unreal Editor 5.7

Additional Notes

Has anyone found a working solution for this? Is there a node or setting I’m missing that forces the alpha channel to write correctly on export?