Having problems with a Sigma DG 28-300mm 3.5-6.3 lens - just not quite right in focus.

[ChrisMadog]

He everyone,

I have a Canon 450D (Rebel I think in the US) dating back to 2009.
The Canon 18-55mm lens won't focus and it looks like the Flex Cable has died so I've got one on order.

I have a Sigma DG 28-300mm 3.5-6.3 lens and while it works, the image quality just isn't 'quite right'. It always seems to be that little bit fuzzy.

Has anyone found some little bit of 'magic' to get it right ?

Kind regards,

Chris

[Waddizzle]

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@ebiggs1 wrote:

First off a lens is what a lens is. It can not change after it is manufactured.  It can't get any sharper or any less.  It can suffer from alignment issues.  Only Sigma is likely able to perform this adjustment.  I have never used this Siggy in question but I can tell you lenses with a zoom ratio of 11 to 1 are never going to be the sharpest tack in the box.

Now for focus adjustment.  Like I stated you can not make it any sharper.  This adjustment simply moves the pin point focus distance.  If this is off, something in your photos will still be in focus. Just not where you thought.

Lastly is user technique.  How you are actually using the lens.  In other words it could be you and not the lens.

"I'm at a loss as to what to do."

I do have a extra question for you.  Was the lens ever real sharp and has this happened recently?

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The only person around here making the claim that AFMA can make a lens sharper is YOU.  While you may not want to recognize it, there is a difference between compensating for the focus behavior of a given lens, and "making it sharper".  As always, I find your false and condescending assumptions to be offensive.  

[ebiggs1]

" As always, I find your false and condescending assumptions to be offensive. "

Easy solution.    Stop reading them!  I wish you would.

[Waddizzle]

Try turning off the OS, optical stabilization, if it has it.  Use it only if you are moving the camera, such as when panning.  Otherwise, leave the OS turned off, and try to maintain a high enough shutter speed where you don't need OS.