Sigma 30mm f1.4 back focus

Started Oct 11, 2006 | Discussions thread
MWeston Contributing Member • Posts: 791
Re: Back focus issue with Sigma 30mm f1.4

David, Your otherwise charming photo is indeed back-focused, unless your were most interested in that hair on her head, i.e. a few inches bac from her eyes. Perhaps I am oversensitive, but possibly because I use my 45P and 28 f/2 AIS (both MF lenes) a lot, I know that if my daughter's eyelashes can't be seen, it is nobldy's fault but my own. Im my experience, precise focusing like this almost requires manual control, and the reliability reports on the Sigma were enough to scare me from it, especially sinc I know that precise focusing at 1.4 is esceedingly difficult in any circumstance.

Here's the 28mm f/2 wide open.

David28 wrote:

I think you will find your problem is not unusual. My first 30mm is
exemplary while the second I bought for my brother had a minor back
focus issue which was promptly fixed by the Sigma people in
Australia for no cost. We rule out the camera as a problem as we
tried different bodies and when my copy was used on his body, it
was spot on.

Couldnt resist sharing an image from the lens - my elder girl, in a
reflective moment ... 1/100 at f2 spot metered +2/3EV, aperture

Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow