diff --git a/imagescrollareagl.cpp b/imagescrollareagl.cpp
index 52f2381..8e57155 100644
--- a/imagescrollareagl.cpp
+++ b/imagescrollareagl.cpp
@@ -225,6 +225,7 @@ void ImageWidget::allocateThumbnails(const QStringList &paths)
     m_thumbnailTexture->setLayers(std::min((int)paths.size(), m_maxArrayLayers));
     m_thumbnailTexture->setAutoMipMapGenerationEnabled(false);
     m_thumbnailTexture->setWrapMode(QOpenGLTexture::ClampToEdge);
+    m_thumbnailTexture->setMipLevelRange(0, 0);
     m_thumbnailTexture->setMinMagFilters(QOpenGLTexture::Linear, QOpenGLTexture::Linear);
     m_thumbnailTexture->allocateStorage();
 }
@@ -419,11 +420,14 @@ void ImageWidget::paintGL()
     }
     else
     {
+        m_vao->bind();
         debayer();
 
-        m_vao->bind();
         if(m_superpixel && m_debayerTex)
+        {
+            f->glActiveTexture(GL_TEXTURE0);
             f->glBindTexture(GL_TEXTURE_2D, m_debayerTex);
+        }
         else
             m_image->bind(0);
 
@@ -760,7 +764,7 @@ void ImageWidget::debayer()
 {
     if(m_debayerTex > 0 || !m_superpixel || !m_bwImg || m_imgWidth < 0)return;
 
-    QOpenGLFramebufferObject fbo(m_imgWidth, m_imgHeight, QOpenGLFramebufferObject::NoAttachment, GL_TEXTURE_2D, GL_RGBA16);
+    QOpenGLFramebufferObject fbo(m_imgWidth, m_imgHeight, QOpenGLFramebufferObject::NoAttachment, GL_TEXTURE_2D, GL_RGBA16F);
     fbo.bind();
 
     f->glViewport(0, 0, m_imgWidth, m_imgHeight);
@@ -774,9 +778,9 @@ void ImageWidget::debayer()
     f->glViewport(0, 0, m_width, m_height);
     m_debayerTex = fbo.takeTexture();
     f->glBindTexture(GL_TEXTURE_2D, m_debayerTex);
-    f->glGenerateMipmap(GL_TEXTURE_2D);
     f->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
     f->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+    f->glGenerateMipmap(GL_TEXTURE_2D);
 }
 
 void ImageWidget::updateScrollBars()