Occluding the dot…it doesn’t always work.

I had an interesting experience in yesterday’s red dot class. Two people both had different corrective lenses for each eye. The dominant eye was corrected for distance (target focus) and the non-dominant eye corrected for near vision. Normally, when shooting occluded, both eyes are focused on the target plane and the dominant eye sees the dot, but nothing further. The non-dominant eye sees the target. If done properly, your vision stays focused on the target plane and your brain overlays the two images (dot from dominant eye and target from non-dominant) seamlessly into one image and it appears that the red dot is on the target. This forces, your eyes to focus and stay focused on the target.

In the case of these two individuals, their eyes are constantly fighting against each other and the brain‘s ability to converge both images is different than if both eyes were corrected to the same visual plane. Convergence becomes a significant problems in this case. The non-dominant eye, which is corrected to focus close up has difficulty seeing the target with any clarity. The dominant eye, which is corrected to see at target distance, is unable to view the dot properly and because of the occlusion cannot achieve the target focus as intended. The end result was a dramatic shift in their point of impact. The eyes apparently could not properly converge two blurry images and the brain was unable to produce the intended result of seeing the dot on the target (my assessment). Additionally, both people were cross eyed dominant. I don’t know how much more that affected the situation in this case, but they both had a point of impact shift of at least 12”!

If you’ve ever experienced this or can provide more insight, leave me a comment!