Bridge not sharp - why?

[PavelR]

I vote for motion blur (camera [wind...], engaged AF, ...). Try the similar shot (distance, F number) with more light / higher ISO and faster shutter speed - about 1/250 (1/320).

[dilbert]

Did you leave Image Stabilization on?

[aprotosimaki]

I have a Canon EF 70-200 f/4 L and a 5DmkII. I've used this setup regularly for awhile now, and I've come across something I can't quite explain. I recently shot this bridge in Oregon. I used a sturdy tripod (Manfrotto ballhead/tripod combo), so stability isn't an issue. Still, several of these images came out much less sharp than I've been used to seeing from this lens. It looks like motion blur to me, but like I said, I was using a sturdy tripod. I shot at f/8, and even one of the images at f/11 had this same issue. Shutter speed was 1/20 and ISO was 125, and autofocus was directly on the front of the bridge itself.  I can't imagine this lens is suddenly misfocusing so badly.

You say that several of your images came out blurry, which implies that others did not. How do the settings compare between these two sets?

I would suspect mild shake due to the wind or the mirror flipping up. As others have suggested mirror lockup could address this.  But it might just be that your AF had a rough day. Did you try manual focus as well?

[AudioGlenn]

I have another idea (laugh if you want). 

If the camera isn't moving, and the air/humidity isn't what's affecting how the light hits the sensor, wouldn't it be reasonable to think that the bridge might have some slight movement?  maybe enough flex in the wind to show motion blur at 1/20?  I mean, the top tip of the Empire State Building sways from side to side.  Either the bridge is moving slightly or the platform you're standing on is moving.  Any civil engineers on the forum?

[sandymandy]

I think metal buildings can sway but not concrete buildings like the bridge in the photo.

[weixing]

Hi,
   How heavy is your tripod? Make sure your tripod is steady and your setup is heavy enough... if you are using those carbon tripod, your setup might not be heavy enough to prevent the slight shake that cause by wind, people walking nearby & etc. You didn't see your camera shake, doesn't mean the camera didn't shake... at 1/20s, a slight shake during the exposure can cause your image to be blur. You can use the hook (a lot of modern tripod had that) below the tripod to hang something heavy to increase the weight of the setup.

   Best is to increase your ISO to get a higher shutter speed. If not, I recommend you to use live view to focus at the object using 10x, make sure everything is lock down and make sure you see that the image is perfectly still before you trigger the shot... also, try to be as still as possible when trigger the remote cable... don't laugh... during some macro shot, I can see the image shake a bit in live view when I move my feet a bit.

   Also, the blur might be cause by air turbulence which is very possible by looking at your image... the temperature different between the heated stone bridge and the cooler environment in the shadow might create some air turbulence which blur the image.

   Just my $0.02.

   Have a nice day.

[cocopop05]

I have a Canon EF 70-200 f/4 L and a 5DmkII. I've used this setup regularly for awhile now, and I've come across something I can't quite explain. I recently shot this bridge in Oregon. I used a sturdy tripod (Manfrotto ballhead/tripod combo), so stability isn't an issue. Still, several of these images came out much less sharp than I've been used to seeing from this lens. It looks like motion blur to me, but like I said, I was using a sturdy tripod. I shot at f/8, and even one of the images at f/11 had this same issue. Shutter speed was 1/20 and ISO was 125, and autofocus was directly on the front of the bridge itself.  I can't imagine this lens is suddenly misfocusing so badly.

You say that several of your images came out blurry, which implies that others did not. How do the settings compare between these two sets?

I would suspect mild shake due to the wind or the mirror flipping up. As others have suggested mirror lockup could address this.  But it might just be that your AF had a rough day. Did you try manual focus as well?

I agree, it may be the AF.  This may sound stupid as you have probably already tried this, but I would set the lens to MF, then use live mode with largest magnification and then adjust the focus until pin sharp.  Then switch out of live view and take the photo. 

Again, I apologies if my advice is very obvious, just posting this in case you have not tried it yet.

[J.R.]

I agree, it may be the AF.  This may sound stupid as you have probably already tried this, but I would set the lens to MF, then use live mode with largest magnification and then adjust the focus until pin sharp.  Then switch out of live view and take the photo. 

Why not take the shot in live-view itself? It has the added advantage of avoiding the mirror slap.

[GammyKnee]

You should have used a bridge camera rather than your 5DII. They are after all specifically designed for this kind of photography. 

Seriously though, it really looks like motion blur to me. As to what caused it, it could be one thing, or a combination of things.

I can't find the link but someone did a vibration test on a range of tripods and it's surprising just how long a little vibration from touching the camera, or from a breeze, or from the mirror itself can take to damp down, even with a really expensive well respected tripod & head.

I've now come round to always shooting from live view when doing a landscape, with silent shutter mode 1. I frame the shot through the vf, slip into live view, give it at least ten secs for residual vibration to damp down, then take the shot with my cable release. This procedure doesn't protect me from the effects of a breeze, but it has got me sharper shots.

But I would also agree with comments about the shutter speed. The sub 1/60 - 1 sec range leaves you really vulnerable to any movement. Longer is OK. Shorter is OK. But 1/40 is still living on the edge.

[dilbert]

btw, is this the Bixby Bridge?

[Northstar]

agree with others that 1/20th is too slow.....there is almost no discernible difference in IQ at any ISO under 800 on that camera so why not use it and shoot at a faster shutter speed? 

[3kramd5]

In reality it's likely a combination of things:
-Motion smearing at the camera level
-Wind/Atmospheric effects
-Wavefront error

That fact that you got good results sometimes suggests an environmental culprit, not faulty equipment (unless it's failing sporadically).

Either the bridge is moving slightly or the platform you're standing on is moving.  Any civil engineers on the forum?

Can the bridge move? Yes. But if it's moving, the camera probably isn't still.

btw, is this the Bixby Bridge?

The columns are different (more ornamental), plus he said it's in oregon.

[rpt]

Looks like mirror slap to me. Reminds me of my first attempt at star trails

However, on pixel-peeping I thought the rear columns looked a bit more in focus but then may be it is that the light on the front columns is distracting my eyes.

[KyleSTL]

You're using the 70-200mm with the optional tripod mount, right?  Just making sure you're not attaching a fairly long, and slightly heavy lens to the camera and using the camera's tripod mount.  Did you use any kind of weight on the bottom of your tripod (i.e. hanging your camera from the centerpost?  I also agree with 3kramd5 about a combination of those three things, and with others that say a shorter SS and higher ISO would have been beneficial.  However, one should not be prevented from using longer SS when adequate support is used and stationary subject matter are being photographed, so I would be more interested in trying to decide the root-cause of your unsharpness than just telling you to dial it up next time.

[RLPhoto]

1/20 is pretty slow. If it was windy that day, the tripod could still shake. Also, when @ 200mm, you might want to engage mirror lockup to prevent mirror slap.

or it could be the lens but I doubt it.