18-55 focus shift on zooming

[puttick]

Hi

I have just bought a 300d, following on from good experiences with a G2 and Ixus 400, and bought it with the kit lens. I know this is not a high end lens but many reviews have shown good results. I am very well versed in 35mm photography, having used SLRs with fixed and zoom lenses over many years (Olympus and Canon) and in general I have found that it can be useful to zoom to the long end to focus critically, then zoom back to a wider angle for shooting. With my 18-55 however if I focus at 55mm then zoom back wide, the focus shifts very noticeably. Is this normal? Perhaps you could check yours...?

Thanks,
Nigel

[Cadwell]

Lists of Canon EF lenses which do not change focus whilst zooming are given

here http://www.rogercavanagh.com/helpinfo/30_parfocal.htm
and
here http://www.photozone.de/bindex2.html under "Canon EOS Lens FAQ"

Whilst these lists may not be exhaustive, the 300D kit lens is not listed so I fear the focus shift may be normal.

[Snorky47]

I'm sure I read in the Instruction Manuel that you must Zoom first and then focus. My experience in the old days of non-af cameras leads me to believe that this may be good advice for modern cameras as well.

[Tom W]

I'm sure I read in the Instruction Manuel that you must Zoom first and then focus. My experience in the old days of non-af cameras leads me to believe that this may be good advice for modern cameras as well.

Zoom, then focus has been my experience in the past. With autofocus, I hadn't given it much thought, but then perhaps I do it subconsciously since I've done it so long.

As an aside, I noticed that I actually have two parfocus lenses! :)

[puttick]

Hmmm, so now we have taken a backwards step. Even in the 80's zoom lenses were parfocal, i.e. didn't change focus when the focal length was changed.

[drisley]

Hmmm, so now we have taken a backwards step. Even in the 80's zoom lenses were parfocal, i.e. didn't change focus when the focal length was changed.

Probably not the cheap kit lenses that were included with the camera as is the case with this lens.