Scope obj size

The maximum exit pupil of 9.65mm is most likely determined by limitations of the eyepiece design.

Also consider e.g. the Swaro 1-6 x 24. Once again maximum exit pupil is 9.6 mm, not the theoretical 24 mm at x1. This strongly suggests to me that Swarovski design their eyepieces for a maximum exit pupil of about 9.6mm, which seems eminently sensible, and can make full use of a 50mm objective at magnifications above about x5. Likewise their 2.5-15 x 56 also has a max. exit pupil of 9.5 mm.

Good point and it would make sense to use the same eyepiece across the range.
 
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Some further data to consider:

The Zeiss Victory HT 2.5-10x50 has a maximum exit pupil of 15mm at x2.5, and and an effective objective diameter of 37.7 mm at that magnification (manufacturer's data). I would expect it to make full use of the 50mm objective from about x3.5 upwards.

FWIW it has a larger effective objective diameter at x2.5 than Tamus has estimated for his 'scope at x7.

Schmidt and Bender variables tend to have maximum exit pupils of 14mm or so.
 
Good point and it would make sense to use the same eyepiece across the range.

The eyepiece is the most complicated and expensive part of any 'scope, and critical to performance. If you are interested in birdwatching or astronomical telescopes you will already know that a good quality eyepiece can cost as much or more than the rest of the telescope. The difference between a really good eyepiece, and the cheap one usually chucked in "free" as a kit can be dramatic.

Thats why low magnification 'scopes with small objectives can cost nearly as much as the big ones. The objective lens is not the main cost driver, its the eyepiece, erector lenses, coatings, reticle and precision mechanics, which have to be built to the same standards.
 
I did both O and A level physics but don't remember going into any detail about scope design.
However, if your learned friend is correct, then he needs to have a chat with the worlds leading optics designers who are clearly taking us all for mugs! If what you're saying is correct, anyone with a scope larger than 34mm has been ripped off!! That will be pretty much all of us on here, oh, and most of the worlds military!
Damn your learned friend! He's so clever!:lol:
MS

Now your getting it!!!

If you decide that the laws of physics can be bent by "the worlds leading optics designers" then no

The worlds military's are not known for buying the "best kit" only kit that does the job and they can get a good discount on.
 
Thank god, your air rifle shooting neihbour has put us all in the picture. We are all mugs for buying top class glass and all the top target shooters - Stalkers and the elite militry marksmen around the globe have got it completely wrong.

Please pass my thanks on the him over the next BBQ - I will just put my three Zeiss Victorys up forsale and buy a forty quid Barska because optically they are the same.


Last point - If we only looked at the laws of physics alone - the Bumble bee should never be able to fly.

Your welcome. And of course the top target shooters pay for their scopes don't they? Or do they get it sponsored to them? And we also know that what ever the bench rest shooting faternity say must be true! They are gods!,,,

As for the cost of a scope! Well you pay what you want. As been commented before the quality of the eye peice is the key. Not the size of your objective!
In my mind that is true. That poster was right! I have spend time looking through astro telescopes. The eye piece can make a huge difference.

As for the elite snippers in military service. I will wont comment on the kit they use as i have no idea whats in current service issue and unless you are a snipper or the pen pushers in whitehall that makes the perchace order, you won't know ether.

I doubt very much that the size of the objective plays a huge roll in the procurement process for issued scopes but maybe build quality and reliability do!

All to often civys think that what ever kit the snippers are useing must be the best. And that in the end it's the scope they are useing that makes the 1.25 mile human target shot count!

That just cheapens the fact that those guys have natural ability to shoot good plus the excellent training they recive and dedication they show in there jobs.

Thank you to those who do that job. It must be a right shitty one.

But if you are selling your victorys and they are a fixed 6x42 I will give you a £100 for it. I don't mind if it's not a S&B. I will slumm it for now.
 
You just stick with your nickko and keeping repeating to yourself - " It is as good as Zeiss - My neihbour said so - It is as good as Zeiss - My neihbour said so "

I will base my opinion on the experience of having used some of the best optics and not the opinion some tosspot from southhampton with a pellet gun that recons that we have all got it wrong and all the schmidt 8x56s are infact no better than a 4x40 Nikko.


BTW and just so you know - Alot of military forces are kitted with some of the best hardware - from the mil grade gen 3 NV scopes that cost several grand per unit and are not availble to civilians - to the 5-25 S&Bs - US optic scopes and Zeiss ( Dont thnk Nikko made it on the list - Maybe you should send them a quick e-mail )

Thanks for your offer regarding my scopes - Probably best if you consult your neihbour before you buy - Just incase he has a therory. LOL
 
My next door neighbour has got a PHD... So when he came over for a BBQ two summers ago. we had a very, very long conversation about how a scope works. He went to great lenghts to dumb it down for me. And I have further condensed it for your information.

ISTM perhaps he over-did the dumbing-down ;) Your post #45 certainly suggests this.

PS: was much beer consumed during this very very long conversation ? :D
 

Now your getting it!!!

If you decide that the laws of physics can be bent by "the worlds leading optics designers" then no

The worlds military's are not known for buying the "best kit" only kit that does the job and they can get a good discount on.

Mate, you appear to be stuck in a parallel universe somewhere between Physics theory and practical reality! I, like most of us probably, started off with a 6 x 42 stalking scope which served me well, but undoubtedly limited me, which was probably a good thing to begin with! Now I look back on it though and occasionally look through the odd one as a reminder, I can't believe how limiting it was!
You are clearly convinced though that your BBQ friend is right though, and that the rest of the shooting world, police, military, etc are all completely wrong! I suspect your friend may have been trying to sell you a scope at the time?
Having served in the military for 24 years, I can assure you that not all equipment purchased is bought at discount!
I doubt many Schmidt PM II's will be replaced with 6 x 42's due to your friends advice!
You would do well to pull your head from your ass and go and look at the world through a decent scope (with a decent objective!)
I also can't believe I am getting grief for having a mere 50mm objective scope!?:???:
Anybody would think I had the bloody 'Hubble Telescope' strapped to a rifle or something!:lol:
MS
 
:tiphat:

You will buy what ever you feel is needed. I have a ziess as well as a Niko. they were purchased before my neighbour moved in.
 
Well a lot has be posted regarding this or that scope, if you can,t hit them is does not matter what scope you have.comparing top of the range military scopes with the models most stalkers buy is stupid talk, swaro 6x42 was standard on police rifles around the world at one time, more deer were killed with 4x 40 scopes than all the vari scopes. My own preference is for 6x42 on 2 rifles and a 4x32 on my lever action quality of glass is what matters, but the millet I have is as good as my swaro.
 
Hi im interested as to what you Stalking chaps on here think is a good size obj , say x50 x30 , i have not really done any stalking myself so just wondered .

The quality of the glass and coatings are more important than mere objective diameter. A top quality 40mm objective will outperform a cheaper 50mm lens. With optics, you get what you pay for. Mid-priced scope such as Leupold, Burris, Vortex Viper, and Nightforce are good value for money. The high end priced brands (S&B, Zeiss, Kahles, Swarovski) do provide better optics but at a substantial increase in price.

For stalking in low light conditions (woodland stalking) light transmission is crucial. In good light conditions (open hill stalking) it is less important. Don't go to a shop to compare scopes in good light conditions, i.e. good daylight. In good light, the pupil contracts which increases our depth of view and even a cheap scope will look good.

-JMS906
 
The maximum exit pupil of 9.65mm is most likely determined by limitations of the eyepiece design.

It makes no sense to use eyepiece lenses big enough to support e.g. a 25mm exit pupil at low mag. It would have to be huge, heavy and very expensive. And pointless.

I expect that this maximum exit pupil probably remains fairly constant as the 'scope is zoomed, probably until about x5. From then on, I would expect the normal relationship to apply, i.e. at x7 the full benefit of the 50mm objective would be available, exit pupil of over 7mm etc.

Sorry, but you ARE quite mistaken.

Tamus, I think your estimate that at x7 only 35mm of the objective lens is used is likely to be completely wrong.

I made a linear extrapolation. That was incorrect but reasonable. So, not as entirely wrong as at first might seem. Anyhow, late as it is, here is the reply to the question, which I received from Swarovski today.

Dear Mr XXXXX
Please find below the reply to your question.

The requested effective objective lens diameter at 7x magnification is 43,33 mm.

Best regards
Christine


Christine Percy
PA to Peter Antoniou
Country Manager UK and Rep of Ireland
Swarovski Optik

01737-856812
 
The above is very interesting. Thank you for posting the reply from Swarovski.

So, a 6x42 scope utilises almost all of the obj lens surface area.

So theoretically then a 6x42 scope with a 34mm main tube would give you the brightest picture?

In the words of the most famous Scott (even thought played by a Canadian)

"you canny change the laws of physics captain"

How true!!!!
 
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all a larger objective lens allows you to do is use slightly higher mag, maybe an extra 2/3x on a 56mm compared to a 40/42 add to this your increasing your line of sight above the centre of the bore, your also increasing the dreaded wobble factor, your scope is wider than your rifle so its more susceptible to damage, and your increasing the weight your carrying, ok maybe it's only a few ozs, then my choice for the job is a good quality 6x40/42, oh and there are less parts to fail on a fixed power
 
I have a 1.5-5x24 which is absolute sh ite at low light, no matter what the mag.
The 2.5-8 x33 Leupold is slightly better but no match for my other 50/56mm S&B, Kahles and Zeiss scopes.
Decades of experience sitting on high seats in moonlight have led to 8x56 being one of the favourites in Germany.
At low light the higher mag can help identify what you are looking at.
edi
 
Ahhh well, you've convinced me...
Chop in all of my the quality glass with over 42mm objectives and buy some cheapo 'Zeiss performance' Nikko Sterling rifle scopes without bollox anti reflection coatings...


Anyone after some crappy ol Schmidts... 6x, 8x, variables, PMII etc?































nahhhh, I'll stick with what works!:D
(have some nikkos, not a patch on the S&B's hence keep em on the airgun toys)
 
Only youngsters can achieve 7mm of pupil dilation; the rest of us have to make do with less. You can get a friend to measure it with a ruler. If you buy a scope with a larger exit pupil than your eye can deal with you are wasting money. Another point not mentioned regarding variable power scopes is that more lenses mean less light transmission. You have to pay more to get light transmission equivalent to that of a fixed power scope. That said, magnification improves the twilight factor. It's the same effect as moving nearer to an object in the dark; the nearer you get the better you can see it. Decisions, decisions!
 
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