Thunder’s compilation algorithm is preset to prioritize text and photo assets over image assets. In the process of compressing your creative to be under the maximum file size allowed by most ad servers, you may see a reduction in quality with your photos. Here are a few tips to reduce the total file size of your creative:
- Use JPG image files over PNG, GIF, or TIFF. JPG images by nature have the highest level of compression among all compatible image types and as a result, will be compressed the least.
- Scale down the dimensions of your image before uploading the it to Thunder. A photo that utilizes the full frame of a 300x250 creative for example does not need to be any larger than 300x250.
- Reduce the DPI (dots per inch) of your image file. In general, 96 DPI is the highest resolution required for photos.
- Reduce the number of frames in your creative. Each frame contains additional code that will add to the overall file size.
- Reduce the number of total assets in your creative. Each asset (photo, text, logo, shape) adds to the overall file size.
- Crop the bounding boxes of your photo so that there is no content outside of the design canvas. If a portion of your image is outside of the border of your canvas, it’s adding unnecessary weight to your file size. (*It may be necessary to have assets outside the canvas border if they will animate into the frame later, though).
- Utilize "Show on all frames" for assets that are used across all frames in the same location, for example a logo. This way, the asset only has to load once.
- Avoid using transparent images where possible.
- Scale down logos to match their final size. Consider using a different logo file for bigger ad sizes.