spritePatch.Draw() loosing color information

Hello, i am drawing a Texture2D on a RenderDevice2D in order to store the generated Image for later use.
Actually this works fine for me in many scenarios, but i got one scenario, where i all Pixels turn Black+Transparency on draw, and i have no idea why. Its MonoGame on WindowsGL. I use Cocos2D on top, but it is not involved here in any way.

    public Microsoft.Xna.Framework.Graphics.Texture2D ApplyShaderToTexture(Microsoft.Xna.Framework.Graphics.Texture2D texture)
    {
        Texture2D blurredTexture = m_gaussianBlurShader.ApplyShaderToTexture(texture);
        //the blurredTexture do have color informationen.

        RenderTarget2D renderTarget = new RenderTarget2D(m_graphicsDevice, texture.Width, texture.Height);
        m_graphicsDevice.SetRenderTarget(renderTarget);
        m_graphicsDevice.Clear(Color.Transparent);

        using (SpriteBatch batch = new SpriteBatch(m_graphicsDevice))
        { 
            // i tried several begin Options here, but all i tried deliver the black graphic, or an entire transparent one.
            //batch.Begin(SpriteSortMode.Immediate, BlendState.AlphaBlend);
            batch.Begin();
           // batch.Begin(0, BlendState.Opaque, null, null, null, null);
            //todo: apply another effect here.
            batch.Draw(blurredTexture, new Microsoft.Xna.Framework.Rectangle(0, 0, blurredTexture.Width, blurredTexture.Height), Color.Transparent);
            batch.End();
        }

        m_graphicsDevice.SetRenderTarget(null);

        return renderTarget;

At a guess try changing the batch.Draw tint from Color.Transparent to Color.White.

thx, i tried this allready.
i get the same result for White, Transparent, TransparentBlack and even Red.

And yes, i have no idea for what the passed color is used for this call :wink:

It must be the ApplyShaderToTexture call. Try just loading a simple Texture without applying the effect and work from there.
Use Begin() and tint Color.White in the draw.

yes the outcome is the same, of course, instead of getting a blurred black texture, i get a clean one…
and i texture2D.SaveAsPng() allready the blurred texture, and it has colors.

I also tryed just to return the blurred texture, and this works well (it keeps the colors). so the further processing of the generated images works as well.

Well, i will set up a Demo Project, i am pretty sure the error will not show up, since we cannot find any error in the source… it must have todo with same weired global settings. !!!