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Old 23rd May 2015, 10:38 AM
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RobF RobF is offline
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Join Date: Mar 2010
Member of: Southampton Buccaneers, Parkstone, South Dorset
Location: Poole, Dorset
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I think there's a belief that changing the gaps by either a bigger side wheel, or changing the parallax track, or a combination of both, means better range finding. It's basic physics. Assuming the lenses offer the same contrast, the better range finding scope will be the one with the lenses that make a bigger blur between 50 & 55 than the other. Wide angle lenses offer less. That cannot be changed, unless you go for a bigger objective, in which case you will need to compare to see what property has come out stronger.

It would appear that what s&b have done is get a wide angle lens system, that lets in lots of light... but because it's more difficult to range find with, they've changed the drive so the gaps are bigger. Solves nothing. It's like saying i'll stick an 8" wheel on my march to make it range find better. It won't, the wheel still turns by the same amount if it's 1" or 8"... all it helps me see is between each yard, but i don't need 10mm to do that... 5mm is fine. Very fine pointer, i can tell to the yard, or close enough I don't care.

You only need gaps big enough to tell what is going on. The more precise and consistent a scope is, the smaller the gaps can be... they don't need to be that big and you only need enough light to give the eye the contrast it needs to determine focus.
Mag does determine the size of the light, so it's obvious why a scope make might try and make that brighter... but mag doesn't mean better range finding. Only size of lens and it's focal length does that.

You can get an indication of the focal length... for 2 scopes of the same mag, the same objective size, the one with a more shallow depth of field will be the one with the longest eye relief.

One could possibly argue that the same problem occurs in HFT, where the one with the lowest parallax error could be the one with the shortest eye relief...

It could be brilliant, but there's no excuse for a super scope being a problem to range find with if it's designed for FT. If that is the case, then they have another dead duck on their hands.
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