There is an extensive table of contents in the article, if one wants to use it as a reference.
The author of All About Instax Film, Lee, has this to say about shaking your instant film photograph:
Should You Shake Instax Film?
No, you should not shake your Instax film because you could ruin the image. You may think that shaking your Instax film may speed of the development process but according to Fujifilm, the manufacturer of Instax film, shaking Instax film while it is developing could damage the development chemicals on the image, causing it not to spread evenly over the image and prevents the photo from developing correctly.In my experience, shaking the image after it comes out of the camera also may make the image blurry and/or cause feather-like patterns on the film. In addition, if you touch the image area while shaking it, you will cause spots on the image.
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