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Noctivid overdrive past infinity (1 Viewer)

etc

Well-known member
I have myopia of -5.5 diopters and it's critical to me that the binoculars can accommodate it by having overdrive past infinity to at least that.

I currently have Swap EL of 2008 vintage and they do that but barely. Though my vision has been stable for the last 15 years, if it worsens by another 1/2 diopter, I will be out of luck with Swaro and will have to migrate to Zeiss that can handle at least -7D.

So the question is, can the new Leica Noctivid handle -5.5D or are they limited to the old -4D that the Trinovid had?

The Leica line of optics is great but the previous models sorely lacked enough overdrive past infinity for me.
 
If I understand the question, with the 10X no. I could not get distance focusing without wearing glasses or contacts with the 10x NV. With the 8X Possibly. I am able to focus uncorrected with the 8X NV, but my eyes are not out at -5.5, they are -3.75.

My understanding of the +/- 4 is to account for differences between your two eyes and therefore are different than the question of how far binoculars focus past infinity in order to bring someone with nearsightedness focus at distance without the person wearing corrective lenses..
 
Meaning this model is a reworked Trinovid with the same focus past infinity limitation and not an entirely new design - I cannot use the entire line without contact lenses or eyeglasses -- too bad since optically, I think they are the greatest.
 
etc,

The Leica Trinovids as well as the Ultravids were/are limited in their capacity to focus past infinity. Leica has addressed this problem in the Noctivid. Between the stops the Noctivid’s focuser makes exactly two turns (720 deg.). From close focus to infinity is 650 deg. So there’s about 70 deg. past infinity. This is definitely better than previous Leica models. Unfortunately I can't go into prediction if this is enough for you, but at least it's worth a try.

Renze
 
etc.

I agree with Renze, it's worth a try. But it will be a close call.
Why do I think that?

I did the following:
I focused the Noctivid to infinity, then put on reading glasses with +2.5 dpt and refocused, then added a second +2.5 dpt pair of reading glasses and refocused again.

It just worked, but with very little travel left. My guess is the Noctivid lets you focus "beyond infinity" safely up to 5 dpt and maybe a tiny bit more, so you will have to see whether that is just enough for you or not.

Good luck !!
 
Last edited:
Good work Canip.

A missing piece of info is, how is your distance vision without correction? If you're nearsighted, he should make it with extra room to spare. But if you're farsighted, which is somewhat unusual, it doesn't look hopeful.

I'm pretty lucky to be only about 1D nearsighted, so I can locate birds okay without glasses. If I was 5D nearsighted though, I'd seriously consider wearing glasses while birding, and would look for a binocular with lots of eye relief, rather than one with lots of infinity overdrive.

Good luck, etc.

Ron
 
Distance vision seems ok, not perfect, but no significant correction needed, that's why I carry reading glasses without which I couldn't write this post;)
 
Meaning this model is a reworked Trinovid with the same focus past infinity limitation and not an entirely new design - I cannot use the entire line without contact lenses or eyeglasses -- too bad since optically, I think they are the greatest.

Optical arrangements

Trinovid B
Leica_cutaway.jpg


2015 Trinovid
http://i17.photobucket.com/albums/b79/aforrester/leica-trinovid-10x42--897.jpg

Ultravid
http://i17.photobucket.com/albums/b79/aforrester/ultravid cutaway.jpg

Noctovid
http://i17.photobucket.com/albums/b79/aforrester/Nvid Cutaway 3D.jpg
 
etc,

The Leica Trinovids as well as the Ultravids were/are limited in their capacity to focus past infinity. Leica has addressed this problem in the Noctivid. Between the stops the Noctivid’s focuser makes exactly two turns (720 deg.). From close focus to infinity is 650 deg. So there’s about 70 deg. past infinity. This is definitely better than previous Leica models. Unfortunately I can't go into prediction if this is enough for you, but at least it's worth a try.

Renze

Renze what is the power and close focus distance of your example?
 
Thanks Renze,

Assuming the close focus was measured with the binocular diopter set to 0 the approximate overdrive would be -3.72 based on the supplied information. If the binocular diopter is set to some other value, it would either add or subtract from the overdrive figure.

FWIW, most of the binos I have checked over the years have very roughly measured about -4d at 0 bino setting. Usually those that are far from -4d are the very fast focusing binos like some of the Nikons, etc.
 
Thanks Renze,

Assuming the close focus was measured with the binocular diopter set to 0 the approximate overdrive would be -3.72 based on the supplied information. If the binocular diopter is set to some other value, it would either add or subtract from the overdrive figure.

FWIW, most of the binos I have checked over the years have very roughly measured about -4d at 0 bino setting. Usually those that are far from -4d are the very fast focusing binos like some of the Nikons, etc.

I don't know about diopters, but I'm nearsighted, that's for sure.

Renze
 
etc.

I agree with Renze, it's worth a try. But it will be a close call.
Why do I think that?

I did the following:
I focused the Noctivid to infinity, then put on reading glasses with +2.5 dpt and refocused, then added a second +2.5 dpt pair of reading glasses and refocused again.

It just worked, but with very little travel left. My guess is the Noctivid lets you focus "beyond infinity" safely up to 5 dpt and maybe a tiny bit more, so you will have to see whether that is just enough for you or not.

Good luck !!

I am -2.5 & -2.75 and I can only just focus to infinity on a NV 8x without glasses, so 5 dpt is optimistic. As far as I remember the 10x had a little more slack. Many other quality optics also have this problem e.g. Swaro SLC and NL 8x at least.
 

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