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Twilight factor


webber
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Thanks to McF, I spent rather less than I usually do during our recent expedition to Scotland.

 

During our numerous hikes with rifle to hand it became evident that my trusty £12 10 x 25s were past their sell buy date. So my thoughts are now on a quality replacement. I rather fancy a pair of Swarovski 10 x 25 Pocket binoculars, and have been on the manufacturers web site. In studying the technical data I have come across an item detailed as Twilight factor of 16, however I dont know if 16 is good, bad, or indifferent?

 

I therefore wondered if someone with more experience in optics than I could shed some light on the subject so to speak!

 

webber

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Webber I am sure someone will come up with an explanation (or a link to wiki) but I can tell you 10x25's even good ones will struggle to pull in light if that is the issue.

You need to stick quite closely to the rule of 7 if you want light gathering, 6x42, ,7x50, 8x56 etc

 

What is you budget?

 

Look at Swaro EL's if it will stretch that far.

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From Swarovski's site:

 

Twilight performance factor

 

This value is obtained from:

 

The square root of: magnification x objective lens diameter

 

The number gives no indication about the quality of the field glass. It describes only its theoretical suitability for use in twilight conditions. In practice, other criteria such as the coating, technical precision and resolution need to be taken into consideration.

 

 

http://www.swarovskioptik.at/index.php?l=e...&c=produkte

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Stuart

 

Thanks, I'm in bed with a back injury, so did the maths in my head, although I suppose some clever jockey will tell me that If I point the lap top south westerley, hold it at 35 degrees and press controll alt and f9 I will have the benefit of a scientific calculator.

 

webber

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And to think that I cried when I broke the cursor on my British Thornton slide rule. Mind you it was in the middle of my HNC mathe exam.

 

When I went to college, they had one computer, it was punch card opperated, and I broke it. Then they got a BBC computer, it took me less than 5 minutes to break that. Then they got anotjhr 6 or so, they also all bought it., and before anyone starts I am not a computer ludite, and I did not send them to their maker deliberatley. Mind you, I think that my grand daughters wrist watch has n

more computing power than the computers we were expected to re engineer the world with.

 

webber

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And to think that I cried when I broke the cursor on my British Thornton slide rule. Mind you it was in the middle of my HNC mathe exam.

 

When I went to college, they had one computer, it was punch card opperated, and I broke it. Then they got a BBC computer, it took me less than 5 minutes to break that. Then they got anotjhr 6 or so, they also all bought it., and before anyone starts I am not a computer ludite, and I did not send them to their maker deliberatley. Mind you, I think that my grand daughters wrist watch has n

more computing power than the computers we were expected to re engineer the world with.

 

webber

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Hi mate may i surgest leopold messa grean 10x50 got my set from the the US £150 THEY ARE AS CLEAR as crystle if you want the details of where they came from pm me and i will sort the adress out for you o no inport tax eather the same ones heare are £700 ish

 

Winchester

 

Thanks for that, I already have two Leupold scopes which are brilliant. I really want a small light pair, but will have a look on Cabelas before I decide to purchase.

 

webber

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hi webber

 

before you part with your hard earned cash i suggest you visit this link http://stores.ebay.co.uk/The-UnixNerds-Domain i have just got a pair of marine 7x50 and went out last night to try them out with my mate and his swarvoski slc 7x50 the results

were unbelievable to me as peresonally i couldent tell the difference as both had a clear view as the light darkend and am well chuffed with them,you can even ring the man and he will explain everthing to you on lenses ect, what model is best for you as. i said earlier i am over the moon with the quality for £80

 

bernie

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Scope and bino's...

 

There are thousands out there and the advice will always be the same, don't buy anything until you have a had good look through it, preferably in the conditions you expect to use them in.

 

I have a 20 year old pair of Ziess BGAT's and when I looked through some new Leupold's to my eyes it was like looking through 2 jam pot's - it is a very personal thing.

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but 20 years ago mate they have come on a bit since then :blink: :) as have other things

You would think so but...

If you do a bit of research you will find there were things used in the production of optics then that are now banned - so they are in fact optics were generally better then, so there :o

Even after all that time they considered to only have been bettered by Swarovski and Lieca.

But I will admit they are bit heavy.

 

Have a read:

 

http://www.opticsplanet.net/zeiss-7x42-bga...binoculars.html

 

"if you're comfortable with a 7x magnification, it would be hard to find a better performer in the world"

 

 

I will proabably sell them when the original warranty runs out.

 

 

 

 

 

 

in 2016 :no:

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I am now searching for a pair of Swarovski compact packet 10 x 25 B in green. The best UK price that I have found is £307.50

 

Lancslad is at the midlands this weekend and has been tasked with bettering the deal. I do however have my doubts. He is just as likely to get carried away, and return with a carrier bag, a free biro, and a lifetime subscription to ferreters life!

 

So if anyone knows where the best Swarovski deals are to be had, please let me know.

 

webber

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Hi John

 

Been to Weston Park today, and stopped off at the Swaro stand.

 

I have a pair of 10 x 42 EL's which are magnificent, but heavy when you have been traipsing the fields for a few hours.

 

I had a look at 8 x 32 EL's and 8 x 30 SLC's, which are very good, but at typical Swaro prices.

 

In the past I have had good deals from F A Anderson, Tim MacAvoy and York Guns

 

Don

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  • 3 weeks later...

Well today I took delivery of a pair of Swarovski 10 x 25, pocket size.

 

Words escape me, the clarity is stunning, and they only weigh 8 ozs.

 

I have been counting the bolts on a works chimney, I just can not believe hopw good these are.

 

My old equivelent, except in quality binos are now in the bin.

 

I cant wait for dusk to give them a go in low light conditions.

 

Many thanks for your help chaps.

 

Don

 

If you want to try them you are most welcome!

 

webber

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