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10x56 SLC vs 8.5x42 EL (1 Viewer)

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I have a 10 year old 8.5x42 EL and wonder how the 10x56 SLC would compare to it optically. Just as sharp?

10x56 SLC does not seem anywhere as popular as the 10x50 EL, which is what I would normally but SLC looks much better from the standpoint of diopters of infinity: 8 versus 5 and I need about 6.

now if Zeiss made a 10x50 version of the 8x42 SF, I might jump on that bandwagon. I really like Leica 10x50 models also of any generation but their diopters at infinity setting is only 4. And I cannot use them with eyeglasses.
 
I have the Swarovski SLC HD 8x56 and I have had the 8.5x42 EL and 10x50 EL. Yes, the 10x56 HD SLC is just as sharp if not sharper than both. The bigger aperture on the 56mm is in IMO more aberration free on-axis than the smaller 42mm and even 50mm. Henry Link explains this characteristic of the bigger aperture binoculars and why he chooses to use a Zeiss 8x56 FL. The EL models are different than the SLC in that they use field flatteners so the FOV is flat and perfectly sharp to the edge. The SLC doesn't use field flatteners but it is almost totally sharp to the edge. Here is Henry's post,as well as,some good reviews explaining the differences between the EL and SLC line. Remember though a 56 mm is almost 43 oz. so they are heavy and big but they have a lot of optical advantages including hardly any veiling glare, almost no CA and excellent low light performance.

https://www.birdforum.net/showpost.php?p=840895&postcount=1
http://scopeviews.co.uk/Swaro10x56SLC.htm
http://scopeviews.co.uk/Swaro10x50EL.htm
https://www.cloudynights.com/topic/446051-swarovski-slc-56-wb-vs-zeiss-victory-fl-56/page-2
 
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Do you have astigmatism in your eyes? If so, every bin will be sharper when used with glasses than without.

And if you are nearsighted you will get a bigger image scale when using bins with glasses than without, because when viewing at any distance with glasses you will be more at the close focus side of the focus travel than at the infinity side of the focus travel (compared to viewing without glasses).

George
 
I have very mild astigmatism to the point where it does not need to be corrected. I tried corrective contacts and they made things worse.

I seriously thought about Zeiss 8x42 SF but the Swarovski 10x56 looks better in every category.And I decided to keep the 2008 vintage EL versus selling it for a few pennies. It's so light and compact. I get it that the 10x56 model seems twice as big and heavy. In an entirely different weight category. But I want to see what I have been missing all this time.

10x50 EL seems nice and would normally be my first choice. It's like 8.5x42 only better. But I cannot believe they reduced diopters at infinity to only 5. that is a total deal breaker for me.

https://www.swarovskioptik.com/hunting/el-50-c20011003/el-10x50-p5222918
 
I am not sure I need "field flatteners" at all. In the new ELs. I have none in the 2008 EL model and it's a solution in search of a problem.
 
From an ergonomic perspective it looks sooooooo much bigger than a UV 10X50. Like you said, diopter limitations and eye -relief, limit the UV for some.

Andy W.
 
From an ergonomic perspective it looks sooooooo much bigger than a UV 10X50. Like you said, diopter limitations and eye -relief, limit the UV for some.

Andy W.
The 56mm SLC's are big but it is surprising how nice they handle. Really when you are using them you forget how big they are. If you hike with them there are a lot of nice harnesses available.
 
I always had either 8x42 or 8.5x42 binoculars. Want to see if I am missing anything with 10x50 or 10x56

I should probably test drive one before committing to it but on paper it looks good, despite being almost twice as heavy.
 
Good as the 8.5 SV is (and it's really very good, better than the equivalent SF to my eye), the big SLC is better optically I would say but you are giving up a fair amount of handling and weight for that image improvement. The SV is my general 'go to' binocular in most cases but I use the 10x56 when I know I need that bit more power/clarity and there is no doubt in my mind it's the better option for tracking very long distance raptors or following a fast flying bird over a darker cluttered background.

FWIW, I thought the 10x50 SV was seriously good too but the SLC is just that bit better for me, albeit in a much larger package. The 8x56 SLC arguably has a yet better image I have to admit but I wanted the 10x to have something different from my existing SV. The 10x54 HT is very close to the SLC (albeit not in a back to back compare) and seemingly a good bit more compact/lighter if you want to consider the Zeiss as well. The 8x54 I found significantly worse than the 8x56 SLC though it has to be said which somewhat strangely I didn't find with the 10x54 which I thought was much better than the 8x54.

Hope that helps.
 
The Swaro 10x50 SV would be my first choice but the deal breaker is the limited diopter value at infinity. I use hardware without corrective eyewear. Check out that value for 10x56 SLC and it's -8 diopters. Check out that value for latest-greatest 10x50 EL and it's only -5D. I need -6D so it's a deal breaker.



10x56 SLC:
https://www.swarovskioptik.com/hunting/slc-56-c20010302/slc-15x56-p5068619

10x50 EL:

https://www.swarovskioptik.com/hunting/el-50-c20011003/el-10x50-p5222918

Swaro 8.5x42 of any generation has a value of -6D at overdrive past infinity. It's there under 'technical data'.
Strangely, the 10x42 EL model has the -8D value versus -6D for the above.


So while thinking about upgrading my 10 year old EL, the realistic choices are:

10x42 EL Swarovision
8x42 SF Zeiss
10x56 Swarovski SLC

I am sure any of the Zeiss 8x56 or 10x56 would work out nicely as well.
 
At this point, I think that you need to ask yourself 2 questions.
1- Do I really need a 56mm compared to a 42?
2- Do I want a 8x or a 10x?
Because optical quality and diopter capabilities are two things, the use you're going to put in them is a main question.
I have an SLC 56, and despite of trekking and hiking with them from the Alps to the Himalaya, they surely aren't my "everyday binoculars" to walk the dog, because they are so big and heavy.

Then, remains the 8x or 10x question.
To sum it up:
8x for low light, wide field and short to mid range observation.
10x for longer range.

Let us know what you choose.
 
At this point, I think that you need to ask yourself 2 questions.
1- Do I really need a 56mm compared to a 42?
2- Do I want a 8x or a 10x?
Because optical quality and diopter capabilities are two things, the use you're going to put in them is a main question.
I have an SLC 56, and despite of trekking and hiking with them from the Alps to the Himalaya, they surely aren't my "everyday binoculars" to walk the dog, because they are so big and heavy.

Then, remains the 8x or 10x question.
To sum it up:
8x for low light, wide field and short to mid range observation.
10x for longer range.

Let us know what you choose.

This about sums it up for me. In no way would I get a 56mm binocular unless I really needed one. I've crossed this bridge over and over. I have the 10X42 SV and the 10X50 SV. So far I've not seen a single instance where the 50mm did anything the 42mm would not and I've tried! Now the 12X50 SV, YES! Probably the same could be said for the 15X56. Unless you are a stargazer, I wouldn't think the 56mm in 8X or 10X would be necessary. IMO the bulk, weight, expense is just unnecessary.

Why are you not considering an SV 10X42? It has a diopter correction of 8 as well. If I were looking for a 10X general usage/birding binocular I'd probably go this route.
 
Good as the 8.5 SV is (and it's really very good, better than the equivalent SF to my eye), the big SLC is better optically I would say but you are giving up a fair amount of handling and weight for that image improvement. The SV is my general 'go to' binocular in most cases but I use the 10x56 when I know I need that bit more power/clarity and there is no doubt in my mind it's the better option for tracking very long distance raptors or following a fast flying bird over a darker cluttered background.

FWIW, I thought the 10x50 SV was seriously good too but the SLC is just that bit better for me, albeit in a much larger package. The 8x56 SLC arguably has a yet better image I have to admit but I wanted the 10x to have something different from my existing SV. The 10x54 HT is very close to the SLC (albeit not in a back to back compare) and seemingly a good bit more compact/lighter if you want to consider the Zeiss as well. The 8x54 I found significantly worse than the 8x56 SLC though it has to be said which somewhat strangely I didn't find with the 10x54 which I thought was much better than the 8x54.

Hope that helps.
Totally agree with everything you said. Although I have not compared the Zeiss 8x54 to the 10x54.
 
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This about sums it up for me. In no way would I get a 56mm binocular unless I really needed one. I've crossed this bridge over and over. I have the 10X42 SV and the 10X50 SV. So far I've not seen a single instance where the 50mm did anything the 42mm would not and I've tried! Now the 12X50 SV, YES! Probably the same could be said for the 15X56. Unless you are a stargazer, I wouldn't think the 56mm in 8X or 10X would be necessary. IMO the bulk, weight, expense is just unnecessary.

Why are you not considering an SV 10X42? It has a diopter correction of 8 as well. If I were looking for a 10X general usage/birding binocular I'd probably go this route.
" Unless you are a stargazer, I wouldn't think the 56mm in 8X or 10X would be necessary. IMO the bulk, weight, expense is just unnecessary. "

The 56 mm is not necessary but once you have experienced the lack of glare, no CA and transparent image of the 56mm it is hard to go back to the smaller aperture. At least when you are not hiking a long ways. For static use the bigger aperture gives you the best image quality IMO. I like to observe Elk and Big Horn Sheep in the parks at dusk from a stand. That is where I will use the 56mm. For hiking the Swaro CL 8x30, CL-P 8x25, or Nikon MHG 10x42.
 
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At least when you are not hiking a long ways.

A quick note on that. I trekked for 3 weeks in altitude (until 18 000 Feet) with the SLC 56.
It is possible and manageable.
But you either have to carry it bandolier's style,
Or use a very good bino harness
(like the Badland or the Alaskan Guide Creation ones).

Carrying a bino harness helps to counter-balance the weight of the backpack too.
 
Any pics of the 8X56 SLC next to other glass. Do not see this glass here in the US, seems like it is more common/available in Europe.

A.W.
 
Unless you have a really plum sample of a 56 mm handy for direct comparison, you will likely never notice what you might be missing with an excellent 42 mm or even 32 mm binocular. The size and weight advantages should outweigh the [slight] optical differences, especially if the bin. is supposed to do daily duty.

I understand what a good 56 mm brings to the table but I would only consider one for fixed location viewing and as more of a reference or boutique-type binoc.
 
I've had 42mm all my life. Never experienced anything outside of it. I do wonder what a larger objective might bring to the table.
 
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