Myopia & Vintage Japanese Porros (1 Viewer)

Good day!

This is for those who have myopia and have used vintage Japanese porros w/o eyeglasses:

I'm -4.5 in my left eye and prefer to view w/o eyeglasses. I'm a pro at the quick eyeglass lift. I'm finding that I can't focus to infinty with certain binoculars. I'm looking to purchase 2 or 3 vintage Japanese Porros on online, but am trying to reduce the risk of picking up a pair that doesn't have enough focus overtravel.

Here are my experiences:

8x30 Carton Prisma (Should work for someone with -5.0...I have a little travel left once reaching focus on infinity)

8x40 Carton Prisma (Should work for someone with -5.0...I have a little travel left once reaching focus on infinity)

Tasco Model 116 7x35. Pretty much have to max out. If it works for me at -4.5 and you are -4.75, they may not work for you. It will be very close.

Tasco 7x50 with no center focus wheel...has individual focus. Old binoculars from when Tasco didn't really give them Model #s. I cannot even come close to focusing to inifinty. Had to get rid of them.

Can anyone add their experiences to this list? It would help me out, and I'm sure others would be thankful. I'd hate to spend 50 or 100 dollars on some nice old Cannons or Nikons...only to find I can't use them.

Thanks!

Tough Crowd, lol. The uncomfortable silence makes me think this thread (or even registering?) was a mistake.

Hello Milway,

I understand your situation. Older binoculars often lacked eye relief and frequently had dioptre adjustment that could not meet the needs of myopes, myself, included. Much older binoculars, from the 1930's -1950's, did have sufficient dioptre adjustment, like the Leitz Binuxit 8x30 and the Bausch & Lomb 8x30, but very poor eye relief. If you are astigmatic, the situation is even poorer. Back in the days, accessory eye cups were sold to accommodate eyeglass wearers, but they are impossible to find.

One can find binoculars with sufficient eye relief, today, but they have reduced dioptre compensation, sometimes within your needs.

I think that this forum may not be the best for getting information on the binoculars you mentioned. You might also try Cloudy Nights.

I think that I may have danced around your question, but that is the limit of my expertise.

Happy bird watching,
Arthur Pinewood :hi:

The Nikon 8x30 EII Porro prism binocular is still available outside the USA along with the 10x35 EII. These are outstanding Porro prisms with very wide FOVs and new modern coatings. They both use the same eye piece and both have about 13.8mm ER. They seem longer than that to me because I typically need at least 15mm to be comfortable but I have no ER problems with them.

The diopter on my Nikon 8x30 EII goes from minus 4 to plus 4 but it also has a bit of over travel on the minus side. How much, I do not know.


Bob

.Hi Milway,
The reason I didn't reply is that I'm longsighted, so I am not ideally equipped to comment.
I was going to suggest that it might be possible for a binocular repairer to adjust the focus of these Vintage Japanese Porro prism binoculars to suit your eyesight, and give you the best range of focus.

I think that Carton made some very high quality telescopes?

In addition, I was going to comment that it may not be completely accurate to exactly quote the focus range of the examples of the binoculars that you mention, as they may vary slightly from one sample to the other.

So basically, it is probably best for an individual to actually try a binocular themselves to see if it works at Infinity.

Personally, I don't wear glasses with binoculars and can use nearly any binocular even those with very short eye relief. It is only rarely that I have had difficulty. I remember a 30×80 being difficult and a few others. Even most extra wide-angle binoculars suit me fine as long as the optical quality is good.

. The Minolta autofocus binocular that I have goes from something like -13 to +5.
I will check later.
It is a very nice binocular and achieves critical focus almost instantly.
It can focus on a moving person also almost instantly.

P. S.
The binocular is a Minolta compact AF 8 8×23 binocular. The field is marked as 6.6°.
The quoted dioptre range with the instruction says -12 to +4. IPD 57 to 70 mm. The same applies to the 10×23 similar binocular.

More details are in the thread 'Large negative dioptre range binocular'.(March 2015?).

These binoculars seem to have the largest negative dioptre range that I have seen.

I have checked the Minolta autofocus binocular on several occasions now against seemingly much higher quality binoculars.
In actual fact, the resolution with the Minolta autofocus binocular is much better.
It is very difficult to achieve critical Focus fast with even the best quality binocular, especially on a moving target.
Here the Minolta autofocus binocular excels.
Looking at a person's face across the road at about 10 m, every detail is seen almost instantly, which is not the case with the better and more expensive binocular.
I really don't know why this autofocus did not catch on, as it has done with cameras.

The resolution of the Minolta is almost as good as with the 2014 Canon 8×25 image stabilised binocular, which uses a tilt mechanism and where the resolution is far better than other eight times binoculars handheld.

Although the Minolta autofocus binocular may seem to be an oddity or a gimmick, it isn't, it works.
The problem is it is larger than a similar binocular. Also to get the best out of it, it should be permanently switched on and instantly available. I presume that this would drain the battery.

The Sony digital binoculars if they can improve considerably, will use autofocus and image stabilisation and I think that eventually optical binoculars may be redundant.

"...Older binoculars often lacked eye relief"
Actually, they almost all (from 1948-1970 Japan)
have 14mm ER or better, if you unscrew the eyecups.
7x50s have even more. You need a little heat and strap wrenches
to wake the cups up sometimes.

I restored a pair of 6x30 "Super-Cotes" today...they needed work, a hinge clamp,
polish/wipe, spray the end caps +wax, some marker. No problem.
Excellent edge to edge field. They will cover to about -5D on the right, -6D on the left.
Independent focus.
I suppose if your eye assymetries go the other way you can flip them over.

I like the binocs with makeup on them.
They usually look like a wreck, scare off bidders,
but they clean easily and they've been pampered.
These had actually been cleaned already, maybe in the 70s.
Excellent grease. Still clear inside.
They did 3 laps at the goodwill...I felt for them, fed them
a few parts. They repaid me.

Hello Milway. My eyeglass prescription isn't quite as strong as yours. My worst eye is about a -3.75 diopter. I've got an old Nikon 8x30E which allows me to focus to infinity sans eyeglasses, with a considerable amount of focus travel remaining for people with stronger prescriptions. I'd estimate that someone with a -5.0 diopter could focus those at infinity. I've also got a Canon 7x35 which seems to have comparable backfocus. One thing about a lot of old Porros is that the focusers can sometimes be tweeked to allow more backfocus (but at the expense of losing a bit of close focus ability).

Milway's problem is that from at least WW2 to today, the standard correction range
is +/- 4 diopters. At -4D, most work for me without glasses, very few don't.
At -4.5D, you end up looking for rare exceptions.

OPTIC_NUT said:

Milway's problem is that from at least WW2 to today, the standard correction range
is +/- 4 diopters. At -4D, most work for me without glasses, very few don't.
At -4.5D, you end up looking for rare exceptions.

Click to expand...

That's a shame. I suppose from the manufacturer's perspective, there's only so much travel distance for the lenses that they can accommodate within the binocular's body, and customers nowadays seem to favor close focusing ability versus back focus for myopic people. I've got a pair of Alpen Rainiers that will focus to about 4 feet on the close end, but can only focus to a couple hundred feet on the far end without my eyeglasses (they probably max out at between -3 and -3.5 diopter).