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Correction to Lens To See Front Sight

Posted: Tue Aug 02, 2005 9:53 pm
by Matt
I would like to know if +1.0 diopter is the typical lens to use in order to see the front sight clearly. I have tried +0.25 and it has slightly cleared the front sight but not enough. Let me know your thoughts.

Posted: Tue Aug 02, 2005 11:00 pm
by four eyes
There really isn't a 'standard', it depends on your eyes. If you can get access to a lens set, try them all until the post is clear and sharp. Otherwise, an Optometrist could help determine what your eye needs.

Posted: Wed Aug 03, 2005 3:49 am
by David M
Correct lens are +.25 and +.50 diopters sphere over and above any distance script, (gives a focal distance of approx. 1.5m).
The best lens will vary depending on the pistol sight radius.

Posted: Wed Aug 03, 2005 4:19 am
by RobStubbs
I think mine was 0.5 or 0.75 but my eyes are just on the edge of being 'normal' and requiring correction in day to day activities - according to the optician who sorted out my shooting lens. As mentioned previously though it will vary from person to person. The best thing is to see an optician and take your gun along (obviously discuss this with them before turning up !)

Rob.

Lens

Posted: Wed Aug 03, 2005 7:05 am
by Ernie Rodriguez
I had my perscription determined and then had the optometrist grind a +1.0 diopter into the main rt lens.So far,up to 25yds, it is ok.You can go to an eyeglass place and(with their permission) bring your gun,try different diopters.Ernie.

Posted: Wed Aug 03, 2005 7:47 am
by jrmcdaniel
I use clip-on .75 and 1D lenses from http://shorinternational.com/SafetyGlasses.htm. Most-often, I use the .75 (and the optometrist checked my sighting at the distance to the front post for me and determined that +.75 was about right). I put tape over all of the left lens in the distance range and just leave a small area of the right distance area clear for sighting. Not elegant but cheap and I can flip-up for changing targets, etc.

I have yellow "shooting glasses" ground to my prescription that I like for both field target (through a scope) and pistol shooting. I think the blocking of blue light probably helps me (floaters and other age-related eye problems).

Best,

Joe

Posted: Wed Aug 03, 2005 7:24 pm
by WSmith
A shooting glasses system starts with a foundation of frame and base lens, then grows with range experience and as conditions change. I wear a plain colored prescriptive correction lens with a +.75 aspherical correction added. I then have the option of adding non-corrective color lenses to suit range conditions, or adding +.25 and +.50 plain or colored lenses via a filter ring. (The corrections are accumulative, i.e., the +.75 lens with a +.25 corrective lens added yields an effective +1.0 correction.)

(Color filters come in a wide range. Some are common - yellow, brown, grey, and dark brown - while some are a bit strange - UV, orange, green, amethyst (purple), blue, and red. As optical quality colored glass has become more and more expensive, start with the common/basic lenses. (Plastic lenses are OK, but I prefer tempered glass as they are less likely to scratch.))

Basically, what you are trying to do is FORCE your aiming eye to focus on your sights. As you shoot a two hour match, or a full day of a four gun event, it may be necessary to add positive correction as your eyes fatigue.

Like all things with the shooting sports, the equipment you choose for success is a very individual choice.

Posted: Thu Aug 04, 2005 2:45 am
by Spencer C
WSmith wrote:...Basically, what you are trying to do is FORCE your aiming eye to focus on your sights...
Not sure that 'force' is the right wording. 'Forcing' the focus to the forsight is what happens when the eye's 'natural' focal length is at some other distance - the correcting lens is there to overcome this and allow the eye to 'naturally' focus at the desired distance.

Regards,

Spencer C

Posted: Thu Aug 04, 2005 4:39 am
by RobStubbs
If you can possibly do it you should keep to the absolute minimum number of different lenses worn at the same time and get the best quality. It is far better to have a choice of lenses at say 0.25, 0.5 and 0.75 rather than add a 0.25 and 0.5 together for example. In some light conditions you will get internal refraction (reflection ?) which can seriously impair the sight image.

Rob.