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Extreme Nearsightedness--Focusing at infinity without eyeglasses (1 Viewer)

Davidae

New member
United States
I am currently shopping to upgrade my binoculars. My #1 hotbutton is the ability of the binoculars to focus at infinity without eyeglasses. I have a -10.5 correction in both eyes, no astigmatism. I would love the ability to purchase APO eyeglass lenses utilizing UD glass at the same quality as my camera lenses. But since our brains are much better at compensating for optical imperfections than digital sensors or film, our cameras and binoculars receive higher quality lenses than our eyeglasses. As a result, I dislike with a passion looking through binoculars with my eyeglasses. An advantage of nearsightedness is the ability to see extremely minute details at short distances. This provides the added benefit of seeing optical imperfections in binoculars, once properly focused, much more than most people. My #2 hotbutton is chromatic aberrations--I can't stand those colored fringes outlining sharp edges, especially in the center of the FOV.

Binoculars compensating for myopic vision at infinity rests in their ability to focus beyond the infinity point (many camera lenses have this ability to allow for thermal expansion). For some reason (I would love to know why), it seems that Porro Prism designs are easier to accommodate this than Roof Prisms. Unfortunately, this function is never listed in the binocular specs, and rarely mentioned on specific models in user forums. For this reason, I will start reviewing specific models and posting the results on this forum. Since my eyesight correction is stronger than about 95% of the population, you can rest assured that if a binocular focuses for me at infinity without my glasses, then they will do just fine for you as well, other eye disorders not withstanding. I would be happy to take requests on specific models for those nearsighted folks that don't have access to a store that carries the model for which they are interested. Just shoot me an email. I will not compare FOVs, nor degree of image stabilization with lesser magnification models (of course there's an inverse relationship between magnification and effectiveness of image stabilization!!!). If you're aware of a binocular model that will focus at infinity without your eyeglasses, please post that, even if you have a rare eye disorder(s). I will only be testing binoculars currently available, however, old models out of production would be of interest.

I'll start off with the binoculars I currently own, the Nikon Action EX 16x50. They are quite amazing, considering they cost under $200.00. They focus at infinity without my eyeglasses very well, although it is almost at the limit of its focusing ability. They provide a very bright image and excellent contrast even at dusk. Chromatic Aberration is minimal, considering the magnification. Focusing is smooth and precise, although I do have to readjust the focus quite a bit. The fit and finish and build quality is quite good, especially for made in China (yes, I still do have an issue with Chinese-made optical products, but there's not much of a choice at this price range). The outer shell is rubberized and fit well in the hands.

I am not very impressed with the Nikon 8x30 Monarch HG. I was barely able to focus without my glasses at an object of about 500 yards away. More than 5x the price of my Nikon Action EX 16x50, with no appreciable improvement in image quality. Very surprised that they are made in China, considering the price. After testing these, I came away very appreciative of my current Nikons.

I am a big fan of Leica and Zeiss optics, and have many Leica R and M lenses, as well as Zeiss lenses. Unfortunately, I was unable to focus at infinity without eyeglasses the Leica 10x42 Trinovid, or the Zeiss 10x56 Conquest. I haven't tested any other models within these two product lines. I have heard, but not confirmed that Leica will make custom modifications to the focus mechanism. I have not heard either way about Zeiss.

I am very impressed with Vortex binoculars. I was able to focus the 10x42 Diamondback and the 18x56 Razor at infinity, without eyeglasses. Build quality, and fit and finish of both models are excellent, comparable to Swarovski. The Diamondback is their least expensive line, and the Razor is their most expensive. It is a safe assumption that every current model in between is of excellent build quality and able to focus at infinity without eyeglasses. The Razor is built in Japan, the Diamondback in China. I was not able to sufficiently test the Diamondback for Chromatic Aberrations, but the Razor was excellent. However, 18x magnification is too high for me to handhold without image stabilization. I was really hoping to test the Diamondback 15x56, but have not yet found a local store that stocks it--for some reason it is a hard model to find, even on the internet. I am also very impressed with the Vortex unlimited lifetime warranty and their customer service. I sent an email to their info address posted on their website, and they responded within 24 hours with the person's first and last name and his phone number. BTW, they are unable to make custom modifications to their focus mechanisms, but it really is a non-issue as it would be unnecessary for me anyway.

The Swarovski 15x56 SLC was excellent as well. Made in Austria. Easily focused at infinity without my eyeglasses and with remaining focus action to spare, and with minimal Chromatic Aberration. To be expected at this price, build quality and fit and finish are excellent. I'm not able to determine if better or worse than the Vortex Razor, as they were tested on different days under different lighting conditions. It is my understanding that for a price, Swarovski will make custom modifications to the focusing mechanism to compensate for certain eye imperfections. However for my purposes, that would be unnecessary.

Finally, for now, are the Canon 18x50 IS image stabilized binoculars, made in Japan. My personal favorite that I have tested so far, and the ones I'll most likely end up purchasing. I found most of the internet criticisms to be unfounded. Sharpness and brightness were excellent, even with image stabilization turned on. They are fully functional without image stabilization, however at this high magnification, the image stabilization is a must when handheld. Minimal Chromatic Aberrations, especially considering the high magnification, and were easily able to focus at infinity without my eyeglasses, with plenty of remaining focus action to spare. Weight is very close to the Swarovski 15x56 and the Vortex Razor 18x56. Without a doubt, I was able to discern far more image detail with the image stabilization than with any other binoculars I have tested, including the Swarovski and the Vortex models. Fit and finish and build quality is a bit more plasticky than I'm used to, however still very good, and will hold up under rainy conditions. The rubber eyepieces I'm told will deteriorate, but at under $20 for a replacement pair, that's not a deal killer for me. A nice touch is the ability to attach screw-on 58mm camera filters and lens hoods. My view is that metal lens hoods would make protective filters unnecessary, however light pollution reduction filters would be an excellent choice for looking at the night sky in urban areas.

Although by no means scientific, I hope nevertheless my comments and reviews are helpful to the nearsighted ones. I would be very interested in what others have to say on the subject of myopia and binoculars, and/or on the models I have tested.
 

jring

Well-known member
Hi,

thanks for the useful data... as for the replacement eyecups - it's probably a good idea to get a pair or two now while they are still easily available. They tend to get rare after a model has been discontinued for a few years...

Joachim
 

dries1

Member
The Monarch HG 8X30 works for many users, and it is a much smaller mag than your Action extreme. Do you have difficulty with lower mag glass i.e. 7 - 8X.
 

Davidae

New member
United States
The Monarch HG 8X30 works for many users, and it is a much smaller mag than your Action extreme. Do you have difficulty with lower mag glass i.e. 7 - 8X.
That's a good question, I don't know. I haven't tested any lower mag models because I don't have a need. I do own an old compact model, Nikon 10x25CF that I bought back in 1987. They also focus at infinity without my glasses. Logically, it would seem to me that the lower the magnification, the more the binoculars would need to focus beyond the infinity point to compensate for nearsightedness. But you raise an interesting question, and I will test a few high-end low magnification models, and post the results.
 

Davidae

New member
United States
Hi,

thanks for the useful data... as for the replacement eyecups - it's probably a good idea to get a pair or two now while they are still easily available. They tend to get rare after a model has been discontinued for a few years...

Joachim
Don't they make generic replacement eyecups?
 

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