Sigma 50mm macro

[Style]

Hi!
A few weeks ago I bought a Nikon D70 with a Ikelite hous and a ds-125 stroba fro manother diver here in sweden. With it I got a 18-70 mm "standart" and a 50mm macro. Already been taking the 18-700mm with me on a dive and my presonal thought about it was that the autofocus didnt work very good in our dark swedish waters. Sometimes it couldnt focus at all and other times it just took a really long time. On land I have sometimes the trouble that the autofocus just focus on the closest range and wont even try to focus on stuff that is lets say 10 m away.

Tomorrow I'am to do some night dives and wont to bring the camera with me, due to the problems with the autofocus parts with the 18-70mm I am considering the macro objective, but how well will it work? And does someone have any ideas about the standard objective?

 

[alcina]

I've not used a Sigma 50mm macro on a Nikon, but it works a treat on the Canon.

I think the 18-70 is the "kit" lens and it probably isn't all that good in the first place. And "less good" lenses are notorious for their poor low light performance. That's why you pay for good glass - the less light it needs the more expensive it is. 10m seems like a long way away, even on land, but I would think it would focus. You may have a bad lens. You can find out more information on the 18-70 at www.dpreview.com

If you are worried about obtaining focus uw with 50mm take a focus light with you. I know the 125 has one, but you might want to take a dedicated one, too.

 

[Style]

I've not used a Sigma 50mm macro on a Nikon, but it works a treat on the Canon.

I think the 18-70 is the "kit" lens and it probably isn't all that good in the first place. And "less good" lenses are notorious for their poor low light performance. That's why you pay for good glass - the less light it needs the more expensive it is. 10m seems like a long way away, even on land, but I would think it would focus. You may have a bad lens. You can find out more information on the 18-70 at www.dpreview.com

If you are worried about obtaining focus uw with 50mm take a focus light with you. I know the 125 has one, but you might want to take a dedicated one, too.

Right now I only have the 18-70mm lens(isnt it called objective in english too? very well, if you say so...) and the 50mm macro so I use the 18-70mm to photo everything thats more than 1m away so 10m+(30 feet) or even 100m+(300feet) isnt very unusual.

I use the built in focus light but I'll prbobly mount an additional divelight on the housing if it doesnt work out well with just the built in.