• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

Wearing eyeglasses while using a riflescope

Stay away from polarization when using riflescopes. It can introduce issues. Also, any tinting of eyeglasses reduces light transmission and can create issues with different coatings. Stay as clear as possible.
The tinting I got simply to reduce eye fatigue and improve contrast, which bothers me pretty much all the time. Curious about the potential issues with polarization. Going to search that up now.
 
I have seen the results of case failures that would have resulted in eye damage and possible vision loss, if the shooter had not been wearing glasses.

I am slightly nearsighted. My glasses are bifocals with lines,d which became a requirement when I hit my early 40s. None of this causes me any problem for my shooting, not image quality, or chromatic aberration.

I have a fair amount of background in the basics of optics and vision. Sometimes I get the impression that some shooters forget that we are not using our rifle scopes for bird watching or photography.

IMO, assuming reasonable image sharpness, the most important quality of a scope used for target shooting is that it not have any shift in point of impact at a given setting. This is not something that can be assumed based on price tag.

Many many years ago, I made a scope rack such that five different 36X scopes could be mounted, side by side, with the whole thing on a sturdy portable table, shooters could adjust the scopes to their own eyes and take as much time as they wanted to view a target through each of the scopes. All of the ring sets were adjustable. I used a single, centered scope to adjust them so it was centered on the same target. Perhaps it is time for someone to do the same thing. Back then 36X was the highest power available for a fixed power scope. The scopes were a Leupold, two different Tasco designs, a Bausch and Lomb, and a Weaver T model.

Have any of you experimented with light tint yellow filters on your objective, eyepiece or as glasses lens tint, for improving contrast and apparent sharpness, particularly in overcast conditions?
Thank you for your contribution.

I started this thread by stating my hypothesis that CA is a major contributor to the degradation of the IQ in a riflescope from shimmer/mirage. My contention is that CA intensifies the shimmer, and if your riflescope is able to control or eliminate CA, it retards the IQ degradation. I further postulated that polycarbonate glasses produce their own CA and thus add to the IQ degradation. I stated that the IQ deteriorates when I wear glasses. I looked to a solution that would allow for protection of my eyes AND not further screw up the IQ of my riflescope.

My current solution is Trivex lenses. I experimented with them and discovered that I could not see a difference between naked eye and Trivex safety glasses, but I could see a difference between Trivex and polycarbonate lenses. To me, that was a win, and I passed it along.

Shimmer/mirage will mess with the IQ of any riflescope, the image from a Majesta in mirage conditions will not win any photograph prizes; that is my goto way of setting expectations. On the other hand, in a Majesta, the aiming black will stay round, and the rings will stay distinct and round even at high magnification. As an F-Class shooter, I live by the rings. That is how I aim my shots.

Using a higher magnification allows the shooter to be more surgical in the placement of the shots. Especially for us old geezers (>70). But when your riflescope gives you an animated image of darkish gray amoeba seemingly on crack surrounded by hazy mishappen rings, instead of a round aiming black with concentric rings, you are forced to dial down the magnification and incur the loss of precision in your aim.

So, when you have a riflescope that controls the CA very well, and there are few of them, the last thing you want is to introduce more CA with your glasses.

I have played with filters in front of objectives some years back. I tried light yellow, dark yellow and red filters. I did not detect any advantages in any conditions at that time. I gave up testing those after a few months. Before someone starts playing with them, let me caution you about a few things. Photography filters are NOT rifle certified. You rarely see a camera experience the recoil that a riflescope will shrug off. Filters can and do break and that could mess up your objective lens and its coatings. Placing a lens in front of your most important lens (in terms of IQ), is not "a good thing" (TM). You are messing with the light path and the optical formula. It could conceivably cause a shift in the aim. If you really want to try filters, consider using a filter behind the eyepiece or on your glasses.

Also, filters will cut down on the light, but will NOT increase depth of field.
 
Chromatic Aberation
It happens in a lens system when the objective bends the light on its way to the eyepiece but all wavelenths aren't brought to a point focus..they are, to one degree or another, spread out. This shows as color fringing in the image. The faster the optical system the more this tends to occur. Modern glass and sometimes fluorite or triplet lens systems almost eliminate this. If you have a cheap rifle scope of high magnification you might see it as a purple haze round the outer edge of the eyepiece image.

Of course you know there is no such thing as color? All there is is light waves of various wavelengths that enter your eye are focused create an electrical pulse to your brain over the optic nerve, and our brain translates those wavelength signals as color. It's really an illusion but a beautiful one.
 
If the glasses have no prescription/magnification and are polycarbonate, is there any CA?
Good question. My guess is that it's probably minimal, but my testing was first a simple "cheap" pair of Trivex safety glasses and if it worked out, I would get a full prescription pair. I have tried polycarbonate safety glasses in the past, and they were all unsatisfactory to my eye. This Trivex pair, just didn't seem to be there at all. And they are so light. At the next match, I will be testing with my prescription pair. This will allow me to look through the riflescope, look at the flags and be able to read properly, and protect my eyes.

At least, that's what I'm looking for.

ETA: Further research revealed that even with no prescription, there will be CA going through polycarb safety glasses and much less in Trivex. It seems just going through the lens material will create CA. Increasing the prescription will increase the CA. That tracks with my observations as my far vision prescription is almost nothing in my glasses. Thanks for the great question and prompting me to do further research.
 
Last edited:
I will state again; coatings do nothing to correct CA. In optical terms, coatings only to control the reflection of light at the air/glass boundary, and they can reduce glare or ghost images (all products of reflectivity.) The do not imp[act or affect CA in any way, shape, or form.

There are also coatings to make the glass more scratch resistant, repel water, mud and dust and make coffee. But coatings don't do CA.
What I have read is
"
  • Coatings can improve contrast by reducing stray light, helping to manage chromatic aberration.
  • Properly coated lenses can enhance sharpness and detail, also helping to mitigating spherical aberration. - Where Light rays near the lens edge focus at different points than those near the center, leading to - a blurred image
 
Last edited:

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
166,865
Messages
2,224,414
Members
79,969
Latest member
JSWIFT
Back
Top