50 vs 56mm Objective Lens

KB1

Well-Known Member
I've always gone for a 56mm Objective Lens but looking at the 50mm, I'm wondering how much of a difference the former makes for light gathering. Also, is the 50mm less bulky on the rifle in terms of general stalking.
Any thoughts?
 
I think 50mm is a good compromise. Something like 2.5-10x50 or 3-12x50 will cover most needs. Get good modern Euro glass.
edi
 
Ive got both a meopta 6/26/56 on a 22/250 and a zeiss 4/14/50 on a 308 and being honest apart from a higher mag on the meopta i cant tell any difference the zeiss is quite a bit smaller in size and seems to suit my 308 which is quite a small lightweight rifle.I would be just as happy with the zeiss on 22/250.
 
Ive got both a meopta 6/26/56 on a 22/250 and a zeiss 4/14/50 on a 308 and being honest apart from a higher mag on the meopta i cant tell any difference the zeiss is quite a bit smaller in size and seems to suit my 308 which is quite a small lightweight rifle.I would be just as happy with the zeiss on 22/250.

makes me wonder if the extra 6mm is worth the extra £ or doesn't justify the cost
 
I have 56mm S&B 's and 50mm Swarovski's you will not notice any light or sight differences just a less bulky scope
 
The sensitivity of the human eye is logarithmic. The difference in a 50mm and 56mm scope is smaller than the difference between a 60w and a 75w light bulb.

Cheers,
Jeff.
 
The sensitivity of the human eye is logarithmic. The difference in a 50mm and 56mm scope is smaller than the difference between a 60w and a 75w light bulb.

Cheers,
Jeff.


What does that equate to in daylight time?.....5-10 minutes??....if so,thats a big difference.....
 
I've always gone for a 56mm Objective Lens but looking at the 50mm, I'm wondering how much of a difference the former makes for light gathering. Also, is the 50mm less bulky on the rifle in terms of general stalking.
Any thoughts?

The biggest gain I've found in quality scopes is not in objective size but in tube diameter. My 1" tube 8 x 56 Swaro was excellent but my 30mm 8.5 - 25 x 50 Leupold VX3 is in a different league. 250+ yards at dawn and dusk or lamping and the difference is just amazing.
 
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Interesting - Leupold beating Swaro. I thought larger tubes only gave wider dialling, with minimal effect on light transmission?
 
Interesting - Leupold beating Swaro. I thought larger tubes only gave wider dialling, with minimal effect on light transmission?
+1 also doubting a fixed Swaro would be outstripped by a variable Leupold - suspect there is something else at play like age of lens coatings and scratches.... :)

To the OP, from a practical perspective you are unlikely to notice a visible difference between a 56mm and a 50mm lens. What it will do is achieve the optimal 7mm exit pupil at 8x instead of 7x - hardly noticable - and that is assuming your eyes are actually flexible enough to utilise the 7mm.
 
I have an 8X56 Swaro and a 3-12 X 50 Zeis Duralite.

I cant tell the diferance in low light capabuility, they are both incredable. but the Swaro comes easier / quicker to the eye than the Duralite and has infantisamaly better day time colour
 
What does that equate to in daylight time?.....5-10 minutes??....if so,thats a big difference.....

Sunrise is about 400 lux; civil twilight about 4 lux. While the true definition of civil twilight is when the sun is 6 degrees below the horizon, it's commonly taken to be 20 to 30 minutes after sunset. So a 10x difference gives you 2 to 3 minutes, while a 20% difference gives you well under 10 seconds.

Cheers,
Jeff.
 
Sunrise is about 400 lux; civil twilight about 4 lux. While the true definition of civil twilight is when the sun is 6 degrees below the horizon, it's commonly taken to be 20 to 30 minutes after sunset. So a 10x difference gives you 2 to 3 minutes, while a 20% difference gives you well under 10 seconds.

Cheers,
Jeff.

I just cannot believe 20% = 10 seconds from light to dark in 50 seconds or how should we understand that?
I would chance to believe the practical experiences more than some dodgy theories. In some countries most shooting is done throughout the night using a strong moon with or without snow, in those areas the 56mm scope is still king for a reason.
edi
 
I own and have tried (evening/night time ambush) several 50mm and 56mm scopes, and my conclusion is the objective size matters an order of magnitude less than other things while actually hunting. In fact 44mm and 42mm objectives have been just as good, while keeping the magnification reasonable. Manufacturers include Meopta, Zeiss, Swaro, S&B. Latest and greatest like Victory HT not included (I've peeked through but not hunted with).

If you want most for your money, get a nice lightweight (500g) scope in 42-50mm that has day and night time illumination and magnification range that suits you (don't trust the manufacturers claim but test the illumination yourself so it's bright enough for day and dim enough for night). Then get low light capable binos that suit you, anything from 7x40 to 10x56 while keeping the exit pupil around 6mm or more. Binos are far more important for night time shooting than scope.

And btw, 56mm has 25% more surface area than 50mm, not 20%.
 
I've always gone for a 56mm Objective Lens but looking at the 50mm, I'm wondering how much of a difference the former makes for light gathering. Also, is the 50mm less bulky on the rifle in terms of general stalking.
Any thoughts?


I forgot to mention the Less bulky thing

Only way i can tell my 50 from my 56 is put them side by side. Even then is not imediatly aparent that the 56 is bigger

Perhaps there are some massive 56m lenses out there but comparing a 56m Swaro to a 50m Zeiss, you can hardly notice the differance

ATB

Mark
 
For dawn/dusk/ night shooting I would always go for the 56mm objective.
You hear the arguments that aged eyes dont allow the pupils to expand and let in light.
My theory is you cant get enough light or a bright enough image. The trade off is weight and or handling. A lot of red deer hunters here like the Zeiss Victory 6-24x72 for night shooting.
We are not allowed to use artificial light for hunting and must rely on good glass and snow/ frost to help. My foxing rig wears a Zeiss HT 3-12x56.
 
I just cannot believe 20% = 10 seconds from light to dark in 50 seconds or how should we understand that?
I would chance to believe the practical experiences more than some dodgy theories. In some countries most shooting is done throughout the night using a strong moon with or without snow, in those areas the 56mm scope is still king for a reason.
edi

No, that was my point about it being logarithmic. Full daylight is not 100% of twilight; it's on the order of ten thousand times brighter (about 18,000 lux in the shade, up to 100,000 lux in full sun).

A strong moon is about 1 lux. But more importantly, it's more-or-less constant, so 20% better will be 20% better for hours. The presence or absence of snow, though, will make a much bigger difference than a 50mm vs 56mm scope. (The albedo of fresh snow is on the order of 80%.)

But by all means go with what works for you. I'm not trying to tell anyone what to do; I just find the science of vision quite interesting. (I'm an amateur astronomer as well, which is how I got in to that end of things.)

Cheers,
Jeff.
 
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