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Porros for less tiresome views as we age? (1 Viewer)

Hey all... does everyone here do this? I almost always open up the barrels till I get the classic overlapping circles (like how an image viewed through binoculars is normally depicted in films). Closing the IPD to the point I get the single circle, for me, makes the view too constricted, and I also feel the distance between barrels is too narrow for my eyes. I have noticed though - with a binocular like my 8x30 Oberkochen (which has quite poor light transmission by today's standards), if you close up the barrels to a certain point the image seems to get quite a bit brighter.

I don't have a particular way to set it, whether opening or closing to it-just til it feels right. I just measured my IPD in the mirror, and then went and measured the BS 10x32s, and they were open a little further than my measured distance. But yes, me too-if it feels constricted, I open it up some to where it feels better-again, it seems this is an individual thing, and so hard to say pat that it should be this way or that, because each of us is different, with different eyesight parameters.

Interesting observation though, Patudo.
 
A porro prism binocular is a much simpler design than a roof prism with fewer optical pathways. For that reason a good porro-prism is easier and less expensive to make than a good roof prism. That is why a porro is always better optically for the dollar spent than a roof. Also, because of the simpler optics in a porro they transmit light better in general than a roof. A lot of the porro's easily achieve 95% transmission and not to many roofs hit that number. Unless you are talking an alpha roof a porro will seem more transparent because of these reasons also. There have been a lot of threads discussing this. If you compare a roof and porro binocular like the Nikon 8x30 E2 and the Sightron 8x32 SII Blue Sky the E2 will give you an easier view.

That's fine, but the question was how the different configuration of prisms made one glass "easier on the eyes" than the other one.

You have simply enumerated the differences, of which I was already aware.

I don't imagine there is any literature to cite, because I'm pretty sure that "easier on the eyes" cannot be quantified.
 
Barry,

Have you checked that your and the IPDs are the same?

OK, just played around with this, and the BSII's were open slightly more than my measured IPD, so maybe it had some effect on my eyestrain. But I don't remember having any trouble setting the IPD in any bins before-it is a pretty natural step for me in using binoculars.

But, what has always caused me more trouble setting is the diopter, since my left (non-dominant) eye is somewhat worse in vision than my dominant right eye, and most times I pick a spot to set it at a mid distance from my usual focusing points for near and far use, if I have the lighting conditions I need to set it easily.

So, I reset the diopter a couple of times (bad lighting-harsh high contrast and then low contrast), and now the setting is more + than before, and it seems to be working for me now-no eystrain to speak of, other than typical allergy symptoms that work against viewing through binoculars any day. But maybe the diopter setting was the problem in the first place? I remember looking through them, and then taking them away, and getting that strange feeling like the collimation was off-so could that be down to the diopter setting moreso than the ipd setting?
 
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The last opticians I used have IPads that measure fittings for frames. These measure IPD.

I use an inexpensive stick sliding micrometer to set the IPD and leave it that way.
 
Hey all... does everyone here do this? I almost always open up the barrels till I get the classic overlapping circles (like how an image viewed through binoculars is normally depicted in films). Closing the IPD to the point I get the single circle, for me, makes the view too constricted, and I also feel the distance between barrels is too narrow for my eyes. I have noticed though - with a binocular like my 8x30 Oberkochen (which has quite poor light transmission by today's standards), if you close up the barrels to a certain point the image seems to get quite a bit brighter.

It certainly SHOULD NOT make it too restricted. If you are getting the overlapping circles (the figure 8) like in the movies, you’re way out of collimation, unless you're looking at a VERY close target. The movies offer such an image to show the moviegoer that someone is looking through a binocular—it’s strictly a Hollywood crutch. That view has nothing to do with what a well-adjusted bino SHOULD be offering your eyes. :cat:

Bill
 
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That's fine, but the question was how the different configuration of prisms made one glass "easier on the eyes" than the other one.

You have simply enumerated the differences, of which I was already aware.

I don't imagine there is any literature to cite, because I'm pretty sure that "easier on the eyes" cannot be quantified.
"Easier on the eyes" can't be quantified because it is subjective but you will really notice it when you use your binoculars all day. I just read a post that said a professional wildlife observer that uses his binoculars all day would pay double the price for an alpha binocular because they are easier on his eyes.
 
"Easier on the eyes" can't be quantified because it is subjective but you will really notice it when you use your binoculars all day. I just read a post that said a professional wildlife observer that uses his binoculars all day would pay double the price for an alpha binocular because they are easier on his eyes.

I saw the same post, but that still doesn't address the question of does a different configuration of prisms have any effect on that property.

You seem to be addressing everything but the question, so I'm confused.
 
I saw the same post, but that still doesn't address the question of does a different configuration of prisms have any effect on that property.

You seem to be addressing everything but the question, so I'm confused.
With a porro you have only 4 reflective surfaces but in a roof you have 6 reflective surfaces plus the prism in a roof needs to be phase coated so there is more chance of optical aberrations in a less expensive roof because there is more chance of errors which can lead to eye strain. It is kind of like your glasses prescription being off a tiny bit.
 
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"My 8x32 Sightron is pretty much perfect in regard to smoothness, whereas the 10x32 has just the tiniest amount of stiction when you are trying to fine tune it after you stop and manoever back and forth."

Perhaps that's why Sightron discontinued the 10x32, yet still produce the 8x32BL.
 
"My 8x32 Sightron is pretty much perfect in regard to smoothness, whereas the 10x32 has just the tiniest amount of stiction when you are trying to fine tune it after you stop and manoever back and forth."

Perhaps that's why Sightron discontinued the 10x32, yet still produce the 8x32BL.
I had the 8x32 Sightron and I didn't have a lot of love for the focus wheel. It was too hard and it had too much stiction. In my experience Nikon has the smoothest focus wheels with just the right tension and Zeiss and Canon are second. A nice smooth focus wheel is important to me. It just makes using the binocular more enjoyable if you don't have to struggle with a sticky focus wheel. I gave up on Swarovski's after having three of them with sticky focus wheels. They say the newer FP models are better but I haven't tried them yet. The worst focus wheel I had was the Swarovski Habicht 8x30. You have to have STRONG fingers to turn it I don't care what anybody says.
 
"In my experience Nikon has the smoothest focus wheels."

Ah, you're just saying that because it's true!

Bill
 
With a porro you have only 4 reflective surfaces but in a roof you have 6 reflective surfaces plus the prism in a roof needs to be phase coated so there is more chance of optical aberrations in a less expensive roof because there is more chance of errors which can lead to eye strain. It is kind of like your glasses prescription being off a tiny bit.

OK, now I see your point.

I frankly don't know the answer, but I suppose that's plausible, the roofs being more critical.
 
I had the 8x32 Sightron and I didn't have a lot of love for the focus wheel. It was too hard and it had too much stiction. In my experience Nikon has the smoothest focus wheels with just the right tension and Zeiss and Canon are second. A nice smooth focus wheel is important to me. It just makes using the binocular more enjoyable if you don't have to struggle with a sticky focus wheel. I gave up on Swarovski's after having three of them with sticky focus wheels. They say the newer FP models are better but I haven't tried them yet. The worst focus wheel I had was the Swarovski Habicht 8x30. You have to have STRONG fingers to turn it I don't care what anybody says.

You just need to focus them on infinity and look at birds that are farther away. :-O
 
As I get older steadiness becomes a key factor. I need something that has a c of g that roughly corresponds with the base of my thumb that provides the main support point. I have a narrowish ipd that means that porros are usually better than roofs for this reason. My fingers are strong enough for Habicht focussers, but not steady enough, compared to my arms anymore.

I have deep eye sockets and find narrower eye cups easier than the bigger kind as I can lock them against my skull.

I am long sighted so eye relief is no problem.

So what works for me in my septegenarian years for all day use at the 8x30/40 end of things are some porros. For walking, and occasionally finding something to look at, I am happy using my old FL roofs as I can hold them steady enough for short term use.

Theorerical performance doesn't count for a lot if you're not physically up to achieving it.

We are all built differently, a bit like the old cars I used to fix when young, and it does't matter how nice and shiny that new carburetor is that you just bought, sometimes the old and dodgy one just runs better.
 
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