8x56 Binocular advice needed

CabinFever

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Hi all, I'm a little surprised my password still worked...I've missed this place.

Does anyone have significant experience with 8x56, or even 7x50 binos? I find myself doing a lot of night and moonlight hunting these days so I can now justify some binoculars specific to the task. Originally my search led me to Steiner Shadowquest 8x56's, and has expanded to include similar options from Minox, Meopta, and Kowa. I did not originally want to spend top dollar for something like the SLC's, however more recently the idea of using bino doublers, or something like the Jim White tripler has come up.

I am curious if anyone thinks doublers or triplers are really a valid option, potentially giving me the ability to use them as a 16 or 24x56. I have attempted doublers on a pair of RazorHD 10x42's but that was ineffective for obvious reasons, primarily light transmission. Perhaps with high quality glass and the 56mm objective it is a more viable option?

If anyone has some advice between the lower end options of Steiner, Minox, Meopta, Kowa I would sure appreciate it. On top of that the same question applies for doublers, specifically the Swaro doubler vs Jim White doubler or tripler. Could using two doublers simultaneously be effective?

Thanks!

Also posted on RS
 
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glass eye

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Swarovskis are pricey so I mulled over this for a long time before I pulled the trigger. I bought the 8x56 because it gives you the most light gathering capabilities. All binos look good in bright daylight but the real test is at dark thirty when big bucks and bulls are on the move to and from their beds. Also, I have put a doubler on it to make it a 16x56 and I compared it side by side with a 15x56 on tripods and it is close to the same. Doublers suck on other optics like 10x40s because 20x40 gives you an exit pupil of 2mm. You want an exit pupil as close to 7mm as possible for maximum light.
 

CabinFever

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Swarovskis are pricey so I mulled over this for a long time before I pulled the trigger. I bought the 8x56 because it gives you the most light gathering capabilities. All binos look good in bright daylight but the real test is at dark thirty when big bucks and bulls are on the move to and from their beds. Also, I have put a doubler on it to make it a 16x56 and I compared it side by side with a 15x56 on tripods and it is close to the same. Doublers suck on other optics like 10x40s because 20x40 gives you an exit pupil of 2mm. You want an exit pupil as close to 7mm as possible for maximum light.
Light gathering is certainly the main idea here, and I've noticed that Steiner's have the highest light transmission rating at 96%

Have you used two doublers, one on each side? Are you using Swaro's doubler or a JW?
 

JLS

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I didn't buy them yesterday, I bought them when I had young eyes in my 30's.
I’m not arguing your choice, and I apologize if it came across as such. I’m merely pointing out some facts relevant to exit pupil, aging, and quality of glass. It wasn’t intended for you, rather the OP.

Carry on.
 
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PrairieHunter

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Interesting research. You are getting into uncharted territory for hunting glass as I don't often see brands like steiner or minox mentioned.

Docter makes an 8x56 as well
https://shop.opticsplanet.com/noblex-docter-optics-ed-8x56mm-roof-prism-binoculars.html?_iv_code=3QC-BI-EDB561-50591&utm_source=google&utm_medium=cpc&utm_campaign=plusbox-beta&gclsrc=aw.ds&&gclid=EAIaIQobChMIkOSJro-S4gIVEttkCh2a2gNqEAQYASABEgIKv_D_BwE

Check what kind of prism they have. The AK will transmit more light but be larger, the SP will be lighter and more compact.
 

glass eye

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Light gathering is certainly the main idea here, and I've noticed that Steiner's have the highest light transmission rating at 96%

Have you used two doublers, one on each side? Are you using Swaro's doubler or a JW?
A doubler on each side doesn't work. Just one Swarovski brand doubler to use as a spotting scope to get a better look at something after finding it with the binos.
 

AggieOutlaw

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Can anyone provide me a technical reason why one would need relatively large objective lenses on relatively low magnification optics? Big = heavy and expensive. It does not necessarily equal "brighter" or "gathers more light." It certainly means larger exit pupil. To each their own, but I found the exit pupil sufficient on a 10x42 even in my 20s. As you age, your pupils get smaller meaning you need less forgiving optics.
 

glass eye

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Can anyone provide me a technical reason why one would need relatively large objective lenses on relatively low magnification optics? Big = heavy and expensive. It does not necessarily equal "brighter" or "gathers more light." It certainly means larger exit pupil. To each their own, but I found the exit pupil sufficient on a 10x42 even in my 20s. As you age, your pupils get smaller meaning you need less forgiving optics.
I also own Swarovski 8x20, same magnification as the 8x56. During the bright light of day they are equal. However, during first light and last light when most game are on the move, the 8x20s are too dark to see through whereas the x56 are clear. You must test optics in poor light, all optics look good in bright light.
 

AggieOutlaw

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8x20 only give a 2.5mm exit pupil which is inadequate when eyes are dilated. The image will be very dark and hard to see.

My question is really about photon density within the exit pupil. All things equal: if glass was identical in quality, would having larger objectives do anything other than change exit pupil diameter?
 

glass eye

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Larger exit pupil ( max 7mm) = more light. Smaller exit pupil= darker image. So yes, the larger objective lens = bigger exit pupil= more light. That's the whole purpose of a larger objective lens.
 

CabinFever

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8x20 only give a 2.5mm exit pupil which is inadequate when eyes are dilated. The image will be very dark and hard to see.

My question is really about photon density within the exit pupil. All things equal: if glass was identical in quality, would having larger objectives do anything other than change exit pupil diameter?
It will take someone smarter than me to answer those questions, I don’t know anything about the science behind it. I suppose I just assume a larger lense takes in more light. The same way that with the 40mm riflescope on my .06 I can’t see with at night, but if I switch to the 56mm on my .375 I can. Same magnification, different size objective makes all the difference.
 

AggieOutlaw

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It will take someone smarter than me to answer those questions, I don’t know anything about the science behind it. I suppose I just assume a larger lense takes in more light. The same way that with the 40mm riflescope on my .06 I can’t see with at night, but if I switch to the 56mm on my .375 I can. Same magnification, different size objective makes all the difference.
This makes perfect sense to me. When your eyes dilate, you need a bigger exit pupil (and thus larger objective) to see.
 

JLS

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This makes perfect sense to me. When your eyes dilate, you need a bigger exit pupil (and thus larger objective) to see.

As long as your eye can dilate to the same size as the exit pupil value on your optics, your are fully utilizing the lens size. Read this article and it does a pretty decent job of illustrating how your eyes change as you age. If you have a 7mm exit pupil value on 8x56 binos, and your eye only dilates to 5mm, you aren't using the lenses as fully as someone could whose eyes dilate to 7mm.
 
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