Canon 70-200 2.8 L question about switch

marcel32us · Post by **marcel32us** » 24 Jul 2009, 17:27

Hi All,

On my Canon 70-200 2.8L there's a switch that changes the autofocus from 1,5 m and up, to 3 m and up.

Anyone know why I would want to change that setting, instead of leaving it on 1,5 m and up??

TIA,
Marcel

Melchior Timmers · Post by **Melchior Timmers** » 24 Jul 2009, 17:32

That switch is for the macro function so you can auto focus in a closer range.

Cheers,

DJdeRidder · Post by **DJdeRidder** » 24 Jul 2009, 17:38

I think setting it on 3m and up will help avoid misfocus on subjects closer than 3m (people's heads, a pole, grass stalks etc). Never really tried it, for aviation I always set it at 3.0m and up.

I'm not sure if 'macro' is the right term for the 1.5m setting. You need special lenses for real macro photography.

bramos · Post by **bramos** » 24 Jul 2009, 17:51

I'm sorry to say so, but that macro-stuff is bollucks.

The switch is a so-called Focus Range Limiter. It increases AF-speed: if you tell the lens it only has to focus from 3m to infinity, it doesn't 'try' the 1.5-3m range. For aviation photography and most other telephoto uses you can leave the switch to 3 metres.

Warthog 71 · Post by **Warthog 71** » 24 Jul 2009, 18:17

Hola Marcel,

Setting it on 3m means it will focus between 3 meter and X> (endless) and will not focus on any objects closer then 3 meter. It only speeds up the AF when you miss focus, as a part of the total range is not used.

Grtz,

Marcel

marcel32us · Post by **marcel32us** » 24 Jul 2009, 20:12

Thanks guys,
That clears thing up.

Marcel

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