In another thread, someone mentioned that having an astigmatism and using a red dot sight could mean the dot is blurry. I had no idea about this. Many years ago (about 1999 or 2000), I had a cheap Tasco red dot on a Super Redhawk and the dot was kinda "starburst" like. I just figured that was...
Astigmatism has been an ongoing issue for me. I've tried/used/looked through a ton of red dots (non-prism) over the years. All of them seem to give me fits to some degree, even recently I've noticed it now happening with Eotech Holo sights as well.
- The brighter the dot, the worse the starburst/tadpole/blob effect is.
- The larger size dots, like 6moa size or so, don't seem to cause me issues and I see a clear round circle. Holosun HS407K and Trijicon RMR come to mind as being very good to my eyes.
- Looking through a rear peep style backup sight clears the issue right up, just like previously mentioned aperture devices. But that kinda defeats one of the reasons why I want a red dot to begin with, fast target acquisition and ability to use irregular shooting positions easier.
- In the morning with a fresh set of rested eyes, the astigmatism isn't usually bad enough to cause me fits. Late afternoon into evenings can be another story. As my eyes fatigue, the issue gets worse. Long range days do not help this issue at all.
- Glasses are better for me than contacts in regards to astigmatism.