Originally Posted by UncleFudd
You have experience with this type of sight on other guns. I have heard for years that the ghost ring arpeture also enhances low light. Do you know if this is actually true and if so perhaps some literature on same?
I made these sights because the only factory ghost rings are only 1/4" arpeture and I found this is too constricting. If you decide to do this keep that in mind and try some especially for pistols. I tried both for a long time before settling on the larger hole and it has made a lot of difference including matching up with the standard Trijicon front sight with no filing or other adjustments necessary. It was like it is made for the two. FYI
It is a fact that ghost-ring, or large apertures, let you do better in low light and even limited visibility in general.
A good example is archery sights. I've used a string sight a long time. Most anyone who hunts the dawn/dusk time will agree a 1/4" string sight is way easier to use than a little peep hole.
On an M16/M4, when using iron sights, as sunlight turns to dusk and then twilight you'll find yourself flipping the small aperture down to use the big aperture...because it's a 100% improvement.
I would not say a ghost ring "enhances" available light, it just lets more light get to your eye, letting you superimpose your sight picture during limited visibility. So you opening the aperture from 1/4" to 5/16" effectively gives you better use of light already coming at you.
On that same note, the big advantages to ghost ring sights, reflex and hologram sights too, is you can keep both eyes open while still having a measure of precision, even to the point of shooting strong or weak hand without changing anything for your dominant eye. Try that with notch-sights then with ghost ring sights and there is no comparison. Moving while shooting/moving targets etc...
I wish I knew some literature related to handgun shooting on low light etc...seems to me that in CQB literature the techniques are for darkness. I believe you'll find more info related to shooting in low light by reading about hunting around dawn/dusk. I do remember reading something from J. Cooper about youth should be taught to use an aperture before learning optics.