Dark vs. transparent blinder for bright outdoor

[seamaster]

What is everyone's feeling about using dark blinder while shooting in bright light environment?

Bright light, pupils constrict, depth of field increase, target too clear.

Use dark blinder, consensual pupil dilation of unpatched pupil. As pupil dilate, depth of field is narrow, target is blurrier.

So dark patch for bright day, transparent patch for darker environment.

I am sure the dark and transparent patches of the shooting glasses are not for aesthetic show only?

[Spencer]

it appears generally accepted that the amount of light to each eye should be (roughly) equal - i.e. translucent (i.e. cloudy) occlude.

My oops - 'opaque' edited to 'translucent'

[seamaster]

What I meant was dark opaque (no light through) VS. light through opaque patches.

[Ulrich Eichstädt]

The problem is, that the eye doesn't regulate the incoming light by closing/opening the aperture/iris alone, but always in connection to the other eye. You can watch it in front of a mirror, keeping one eye closed (which causes the iris to open) and watching the other iris open, too.

So by using a dark blinder you force this eye to open, but the aiming eye opens up, too, and looses its focus a bit. Always try to regulate the amount of light for both eyes the same, that's more important than black or transparent.

[RobStubbs]

As Spencer and Ulrich rightly say, you want the same amount of light coming into both eyes, to keep both pupils the same. That translates to a cloudy/frosted translucent blinder being optimal. You may even benefit from matching the blinder when you add in a filter on the shooting eye, but I've personally never gone to that level.

Rob.

[dronning]

I believe this impacts people in varying degrees too. I went from a dark to translucent and now clear scotch tape on my lens. Scores went up with the clear tape because my sight picture improved.

[Rover]

The (frosted) cellophane tape is an excellent idea when you don't have a "blinder" set-up. I've used it many times when I didn't have my shooting glasses with me.

Put the tape on the rear of the lens to eliminate a distracting mirror-like effect.

[FredB]

It seems to me that these responses are all missing the point of the original question. The OP understands that less light reaching the occluded eye will likely cause the non-occluded eye's pupil to dilate. That's his point and question. He's asking if such forced dilation might be useful in narrowing depth of field and thereby forcing the shooter's attention onto the front sight. He's suggesting that this technique might be useful in brightly let situations, when the wide depth of field from an extremely constricted pupil might tempt the shooter to focus on the target. That's an interesting and out-of-the-box question.

[RobStubbs]

If that worked, why not just use a dark blinder and a dark filter, to force both eyes open to the same extent? You're asking for trouble having unequal light from each eye, its not just about visual perception. As always though, the OP should try it and see if his theory works for him.

Rob.

[jackh]

I use spectacle type shooting glasses. I place a stick on patch before the off eye that is just large enough to block the sight to the left eye. It is less than 1/2 inch across. Light still comes in around the sticker. Placement is important. One plus is it keeps your head position very consistent.

[seamaster]

Thank you FredB for "re-focusing" my question.

[David M]

One of the reasons for using a opaque type blinder of minimum size is to keep both eyes very similar, same light, same intensity, same glare, same effort.
This is to reduce eye fatigue.
What you are suggesting may work, but I doubt it will work for a entire event.
I use multiple sets of two lens of similar power and tint (two lens holders on Champion glasses), one is occuluded with Scotch Magic tape (double layer). It helps reduce eye fatigue during a full match. Tints are clear, yellow and grey for differing light conditions.