Bridge not sharp - why?

[brett b]

Did you manually focus?

[neuroanatomist]

Didn't use mirror lock. It might be helpful in some situations, but it wouldn't have caused this kind of motion blur.

Actually, a 1/20 s exposure is right in the range of shutter speeds (around 1/60 s to 1/2 s) where mirror slap can result in the camera shake-type blur you're seeing. 

[verysimplejason]

Didn't use mirror lock. It might be helpful in some situations, but it wouldn't have caused this kind of motion blur.

Actually, a 1/20 s exposure is right in the range of shutter speeds (around 1/60 s to 1/2 s) where mirror slap can result in the camera shake-type blur you're seeing.

+1.  I always use mirror-lock it's that slow or slower especially when taken relative to the focal length being used, even on a tripod.  I'd also use live-view to focus manually.  I'm not over-reliant on AF.  For non-moving objects, sometimes it's better to use live-view as this is more accurate.

[agierke]

as neuro stated...around 1/20th of a sec mirror lockup is really needed. the initial impact of the mirror opening and residual vibrations are enough of a percentage of exposure during that speed of shutter to have a significant effect. at even slower shutterspeeds (2 secs +) its its not as big of a concern because the initial moment of impact is far less of a percentage of overall exposure. 

[EOBeav]

Didn't use mirror lock. It might be helpful in some situations, but it wouldn't have caused this kind of motion blur.

Actually, a 1/20 s exposure is right in the range of shutter speeds (around 1/60 s to 1/2 s) where mirror slap can result in the camera shake-type blur you're seeing.

Looks like I just learned something. I can now see where mirror shake would be a bigger issue at this speed/focal length than it would at, say 1/500 or going the other way, at .5.  Thanks to neuro, agierke, jason, et al, for setting me straight on this one. I'm going to read up on doing that with my 5DmkII.

[Studio1930]

And for future reference (as someone else already mentioned), ISO 125 is not the best ISO for that camera body.  Check out this chart that shows the sawtooth noise produced by the type of amplifiers used in the 5D2.  You are better off at ISO 160.

http://home.comcast.net/~NikonD70/Charts/RN_ADU.htm#EOS%205D%20Mark%20II_14

[EOBeav]

And for future reference (as someone else already mentioned), ISO 125 is not the best ISO for that camera body.  Check out this chart that shows the sawtooth noise produced by the type of amplifiers used in the 5D2.  You are better off at ISO 160.

http://home.comcast.net/~NikonD70/Charts/RN_ADU.htm#EOS%205D%20Mark%20II_14

Interesting, I hadn't seen that before. According to this chart, it looks like the sweet spots are ISO 160, 320 and 640.

[John Strung]

Personally, I use live view, set the shutter to a 20 second delay and fire it using the infrared remote.

But in this case, I still thing the blurriness is caused by thermals rising from the canyon.

[brett b]

Personally, I use live view, set the shutter to a 20 second delay and fire it using the infrared remote.

But in this case, I still thing the blurriness is caused by thermals rising from the canyon.

Interesting thought, John. I would never have thought about the rising thermals. Thanks!