Limit or Full??

[bazza]

I've just purchased a Sigma 50mm Macro lens which I am more than pleased with and it has a Limit/Full switch on the body. Can anybody tell me what this is for.

Thanks a lot..

 

[Digital Matt]

This button limits the focusing from the full range, to only the macro range. If you are shooting subjects at non macro distances, you'll want to set it to full, so you have the full range of focus. If you are only shooting macro, set it to limit, so it doesn't hunt as much.

 

[Big Mike]

I might think that it's a focus limiter switch. If so, what it does is limit the range at which the lens will try to focus. For example, if you are trying to focus on something very close, 'macro'...you certainly won't need to use the same focus setting as if you were focused on something 40 feet away. Often, the way a lens works when auto focusing, it will 'hunt' and go back and forth until it finds the focus....if the lens had to go all the way to the end of it's focus range, and back again...it would take longer to focus. So by limiting the focus range, you can improve the speed at which it focuses.

I'm not sure which lens of the range is limited on that range. I'm sure it's in the manual of the lens, if you have it.

 

[bazza]

Thanks guys,i'll try that, cheers

 

[bazza]

Just tried that but it seems that it is the other way around.

When the limit is on, it acts like a normal 50mm lens with no macro. When off it has the full range including the close up.

 

[Digital Matt]

Yes, that is true, I did say it backwards For telephoto lenses with this function it is opposite. Well, at least you figured it out

 

[bazza]

Can't believe the quality on these lenses compared to the cheap close up lens attachments i was previously using..