Recently we brought you an article that made headlines around the internet supposedly confirming the damage that 3D Movies can do to your vision. I was just contacted by some of the folks involved in the study wanting to bring out some information that shows the dangers of reporting on nothing but the abstract. If you read the article abstract, it confirms basically what people were saying:
In one experiment, we examined the effect of viewing distance on discomfort and fatigue. We found that conflicts of a given dioptric value were slightly less comfortable at far than at near distance. In a second experiment, we examined the effect of the sign of the vergence–accommodation conflict on discomfort and fatigue. We found that negative conflicts (stereo content behind the screen) are less comfortable at far distances and that positive conflicts (content in front of screen) are less comfortable at near distances. In a third experiment, we measured phoria and the zone of clear single binocular vision, which are clinical measurements commonly associated with correcting refractive error. Those measurements predicted susceptibility to discomfort in the first two experiments.
However, if you read the full paper (Available online & in PDF at the link below), you’ll see the actual paper is a bit different that reported. In the conclusions they compare their recorded data on discomfort to cinematographer guidelines on working with 3D stereo to see how they match up.
Our data imply a larger range for comfortable viewing than the percentage rule implies, but this difference is undoubtedly due to criterion differences, i.e.,
in the magnitude of discomfort that is assumed to be allowable in the two cases. However, our data also imply greater tolerance for near disparities relative to the
percentage rule than for far disparities. We suggest that the percentage rule be modified to incorporate this asymmetry, i.e., that 3–4% be allowed for near disparities
and 1–2% for far disparities. We conclude that the percentage rule, coupled with reasonable assumptions about viewing distance, is a fairly reasonable guideline
for creating comfortable viewing, but it may require some modification.
So that’s the true value of the study. Coming up with more accurate & experimentally proven figures for 3D Stereo parameters will only improve things in the long-run, hopefully eliminating nausea and headaches that so many people complain of.
The zone of comfort: Predicting visual discomfort with stereo displays.
