17-70 sigma

[Baddrummerboyy]

Im guessing this is normal. I take a lot of picture and most with the same setting. About 70% of come out really sharp and other 30% does not. Sometime I get some really sharp picture. Is it normal to have some picture come out a lot sharper then other with the same light situation and setting?

[condyk]

I would say so ... the shooter has the biggest impact on any shot. I would say that ratio is very good.

[tekkie]

what was your aperture set to? if its 2.8 then thats probably why, thats what its supposed to do

[Big WIll]

Do sigma do a fixed aperture 17-70. Like 17-70f2.8? All about the shooter!

[TMR Design]

I would agree with the other replies. If you are using a narrow depth of field then this is something that can happen a lot if you're not careful. Try setting your aperture to f/8 and see if you get the same results.

[Layston]

Also, check your shutter speed on the "soft" images. If the shutter speed was longer than 1/(focal length) then maybe you had slight hand shake on those images.