Not quite - the convertor does not move, but it protrudes a little from the front of its housing, so if the rear elements of your lens come back too far they will touch - not ideal! You can probably gauge for yourself if you are OK, but seeing how close to the back you can get the rear elements of your lens at all zooms and all focus points.
> -----Original Message----- > From: Gary L. Murphy [mailto:[EMAIL PROTECTED] > Sent: 07 November 2003 14:52 > To: [EMAIL PROTECTED] > Subject: Re: Sigma EX converter > > > Ryan Lee wrote: > > >Probably a stupid question, but manufacturer's instructions > say which > >lenses the Sigma EX 2x converter works with, e.g. the EX 300 2.8, 50 > >500 4-6.3 etc. But say you had one and you hypothetically > put your EX > >28-70 2.8 on it (ridiculous I know, given you lose 2 stops for the > >focal length of, yay, 140mm), how would this 'spoil' your > lens, or is > >it entirely harmless? > > > > It's my understanding that damage could occur to your front element > since the rear of the converter moves. This is the reason > given to me > by Sigma USA concerning my 2x EX sample. > > > > > -- > Later, > Gary > >
