export default {
  image: {
    // top offset of the viewport you want to begin displaying your content
    loadingOffset: {
      placeholder: 300,  // extreme low resolution image to display at first
      image: 80          // real image to display
    }
  }
}

export default {
  image: {
    // top offset of the viewport you want to begin displaying your content
    loadingOffset: {
      placeholder: 600,  // extreme low resolution image to display at first
      image: 200          // real image to display
    }
  }
}

enlarge the offset of image to display