The key may be that the illustration of the sausage finger trick shows a very distinct "chunk" of floating finger, and that isn't what you really get.
As for doing this for 30 minutes? Don't do that. Nothing is worth damaging your eyes.
The things I had to do to get the effect were move my hands closer or further away from my eyes, as well as varying the distance that my fingers were apart from one another.
If this is going to work, it takes only a few seconds to see the result. If you are doing it wrong, then staring at them for 10,000 years will not help. [ DangerNerd's advice column | Ask DangerNerd A Question ]
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