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Old 17th February 2016, 09:36 AM
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RobF RobF is offline
My Empire of Dirt
Join Date: Mar 2010
Member of: Southampton Buccaneers, Parkstone, South Dorset
Location: Poole, Dorset
Posts: 10,170

Something clearer to understand...

The top blue i'll use at sub 8 if i know it's staying below 8, and wont be in the sun...

The one below i'll use 8-10/12 depending if i'm in and out of the sun...

The middle one i'll use when temps are above that but below 23

Around 23 I'll be looking to see if the yellow one works, but if it's sunny the chances are that it will swing to the red which is what I use for sustained temps over 26.

What needs to be understood is that sunlight can throw a scope's temp way higher than ambient... as said the other day i was at over 15 degrees on the top of the scope when the air temp was still zero to 2.5 degrees. A silver scope or a bag may help reduce that in that case... but if you're really worried about it then you might adopt other methods which mitigate that. Having done experiments with two identical scopes, one white, one black, if the ambient is one temperature the colour only slows down the shift... sometimes that's not so welcome... sometimes it is.

Other useless scopes include the Leup comp 40x, and S&B FT1, which both shift according to the very people that used them to win the BFTA GP series. I'm sure the 20-50 has as well and that is supposedly shifty.

My deben doesn't seem to display much if any shift in the temperature ranges i've used it in. But no-one seems to like those.. the two 2nds in the worlds, bfta showdown (twice i think) and the bfta euros being flukes with 300 scopes. Just picked one off Ebay brand spanker...
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