Sigma 50-150mm f/2.8

[ian in lancs]

I'm interested in getting one of these for portrait / fashion but I read they are variable in quality. What's everyones experience? How would I go about getting a sharp one without the front focusing error and centering I'm reading about from the testers?

[Simpo Two]

Buy one from a reputable seller, try it, and if it's not right exchange it. Minor focusing issues can be tuned out if your camera body supports this function (Nikon D300 upwards for example)

By 'centering' do you mean vignetting?

[ian in lancs]

Simpo Two said:

Buy one from a reputable seller, try it, and if it's not right exchange it. Minor focusing issues can be tuned out if your camera body supports this function (Nikon D300 upwards for example)

By 'centering' do you mean vignetting?

Centering referred to lopsided sharpness or partial out of focus so I assume the focus axis isn't aligned or focal plane square.

Edited by ian in lancs on Monday 19th October 13:01

[Simpo Two]

ian in lancs said:

Centering referred to lopsided sharpness or partial out of focus so I assume the focus axis isn't aligned or focal plane square.

Oh right, well definitely a candidate for return then. Ophthalmologists would call it astigmatism!

[arej]

A review of it on a Canon:
http://www.the-digital-picture.com/Reviews/Sigma-5...

[ian in lancs]

arej said:

A review of it on a Canon:
http://www.the-digital-picture.com/Reviews/Sigma-5...

yep that's one of the critical reviews...

"All three purchased-retail-new copies of this lens I tried strongly front-focused on both my Canon EOS Rebel XSi / 450D and Canon EOS 40D DSLRs. All three focused consistently, but all focused well in front of the subject. On top of that, one lens had a smudge on an inner lens surface. Yes, there is a chance a forth copy could focus properly, but 0 for 3 is not a good showing and I have to stop somewhere. So my conclusion is that, if relying on AF, this is an extremely soft lens - unusable until f/5.6 at 50mm and f/11 at 150mm in my opinion."

[RobDickinson]

A friend has one on Nikon.

It produces stunning results, is quite small and light for an f2.8 zoom.

He's got +17 dialed in to AF adjustment for the long end and realy needs a different value at 50mm, but saying that he loves it.

[andy-xr]

You spend too much time thinking about whats going to go wrong. Get on and buy a new one, if it doesnt work it's got a warranty!

[taaffy]

Ian you have mail.

Edited by taaffy on Wednesday 21st October 10:02