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Pistol lens diopter survey

Posted: Mon Jan 05, 2009 1:54 pm
by tleddy
Many pistol shooters have special lenses made for their shooting eye to selectively focus on the front sight. Basically, it is a plus spherical addition to the distance 20/20 lens either normal or corrected.

The survey asks what plus spherical correction you are using.

Tillman in Florida

Posted: Mon Jan 05, 2009 2:53 pm
by bruce
+1.50

Posted: Mon Jan 05, 2009 3:07 pm
by jackh
Distance Rx = -.75
Sight Rx =-.75 + 1.00 = net +0.25

Posted: Mon Jan 05, 2009 3:24 pm
by JulianY
+0.5 but i am thinking about going back to 0

Julian

Posted: Mon Jan 05, 2009 3:54 pm
by Fred Mannis
Depends. 0.5 to 0.75

Posted: Mon Jan 05, 2009 8:55 pm
by joecon
Distance Rx = -0.75
Shooting Rx = -0.25 => Effectivly +0.5

Posted: Mon Jan 05, 2009 9:35 pm
by Muffo
I think mine is +.5 but its not right for my eyes. I am going to a different optomitrist on friday to get a new one made. so far i havent found anyone who really has any idea about making a lense for pistol shooters

Posted: Mon Jan 05, 2009 10:24 pm
by Noel
.25, young(ish) eyes. Will be trying .5 at some point.

Posted: Tue Jan 06, 2009 2:52 am
by Chris
i am using ZERO but have been thinking about getting a +.125 to start out with. I tried +0.5 and my eye did not like it.

Diopter corrections

Posted: Tue Jan 06, 2009 3:07 pm
by tleddy
This is very interesting. I could not figure out a way to do a duplex survey in that it would be good to know the age of the users of the different diopter corrections.

Usually we become presbyopic around 40 year of age due to weakening of the ciliary muscles that focus the eye and a hardening of the lens... our arms are not long enough to read the newspaper anymore!!

For myself, I use the 0.75+ and that gives me a nice, clear front sight. Of course I am in my 68th year :-)

Tillman

lens

Posted: Tue Jan 06, 2009 8:43 pm
by david alaways
halfway between .75 and 1.0 so .8725 . I was shooting .75 but got old and 1.0 was too much. Im 50 next week , at 48 I used a 0.0. Im finding out what it means to get older every year.....................David

Lens

Posted: Tue Jan 06, 2009 9:42 pm
by shadow
My optometrist allows me to bring my air pistol with me for the exam. I am farsighted. My shooting prescription is my distance plus 1/2 of the bifocal add.

Posted: Wed Jan 07, 2009 2:01 pm
by guests
Other.

It depends on what the condtions are.

As I stop my iris down, I use increasing + correction.

No Stop/No correction.

Pinhole stop (either very bright or very dim) use up to +1.00

Steve Swartz

Posted: Wed Jan 07, 2009 2:28 pm
by OzzieM
+0.75, prescribed by an optometrist who is familiar with the needs of shooters, being one himself. He requested I bring in my pistol when I made my appointment.

Regarding my prescription I should add, distance from my aiming eye to the front sight is 1.08m/42.5" when in shooting stance.

OzzieM

Posted: Fri Jan 09, 2009 7:34 pm
by higginsdj
OK - Here's a silly question :) What does this lens actually do (or what is it supposed to do)?

I'm a novice and do not use any lens at present in my glasses but would actually like to have something that will 'maintain' the focus of my eyes at the distance of my pistol sights. Is that what these lenses do? ie so the target will always be a blur but my pistol sights will always be in focus (ie immediate focus when I bright them up to aim)

Cheers

David

Posted: Fri Jan 09, 2009 8:27 pm
by Richard H
higginsdj wrote:OK - Here's a silly question :) What does this lens actually do (or what is it supposed to do)?

I'm a novice and do not use any lens at present in my glasses but would actually like to have something that will 'maintain' the focus of my eyes at the distance of my pistol sights. Is that what these lenses do? ie so the target will always be a blur but my pistol sights will always be in focus (ie immediate focus when I bright them up to aim)

Cheers

David
That is what they do.

Posted: Sat Jan 10, 2009 12:11 am
by Spencer
higginsdj wrote:OK - Here's a silly question :) What does this lens actually do (or what is it supposed to do)?
David
More specifically, if properly set up, focus at the front sight.
The target is blurred,
The front sight is in focus
The rear sight is slightly blurred.

A good example is the avatar used by deadeyedick http://www.targettalk.org/profile.php?m ... ile&u=2989

Spencer

Posted: Sun Jan 11, 2009 4:42 pm
by higginsdj
So do these x.xx diopter lenses differ in any way to those made by an optomotrist for shooting glasses or is it that the ones created by the optomotrist are 'exact' and the 0.5/0.75 etc diopter lenses just 'close'?

Diopter corrections

Posted: Sun Jan 11, 2009 5:40 pm
by tleddy
The answer is "yes and no"

Search for "Norman Wong" and read his information on the net... he is an optometrist and a precision shooter as well. Very knowledgeable!!

Now, most people have difficulty determining the difference in 0.25 diopters of correction. There may be some that can decide on 0.125 diopters, but I have yet to meet them.

Basically, you do not want to be too corrected; get to where it is almost corrected and let the eye finish the focus on the front sight. If the power is too much, you cannot then focus on the front sight, rather you end up with a very nice, crisp rear sight.... and that is not what you want.

Erring to the weaker power is much safer!

Tillman

Yes and no...

Posted: Sun Jan 11, 2009 9:45 pm
by tleddy
Clarifying: let's assume that the shooter's vision is corrected to 20/20 at infinity, such as driving glasses. Now, a +1.00 spherical diopter lens is placed in front of the sighting eye.

We now have a "nearsighted" shooter that has the sharp focus, not at infinity, but rather at one meter (roughly 39 inches.

So. what we are doing is making the shooter selectively nearsighted to allow sharp focus on the front sight. Since corrections and eyesight tends to vary from shooter to shooter and prescription glasses as well, one has to experiment a bit with the plus correction to see what works the best.

Our host offers lenses in various powers for the Varga frames at $20.00 each. I advise trying the +0.5 and the +0.75 to start with... the survey suggests that is a good beginning as well.

Another approach is to go to your optometrist and have him put your distance correction to 20/20, then hold your pistol out and have him use his + diopter correction lenses and find the + power that gives the best front sight.

Please feel free to PM me if you need further information - and do look up Dr. Norman Wong for his excellent articles on pistol marksmanship and vision.

Tillman