Bridge not sharp - why?

[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.

 

[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.

 

[John Strung]

The valley under the bridge will act as a chimney causing thermals to rise and the bridge appear to move slightly as the air rises past it. Next time you are in this situation, try turning on Live View and zooming in all the way and I will bet you can see the air movement.

 

[lux]

I agree with the "chimney" effect. I suspect that if you had used video you could have seen the thermals rise kind of like the mirage on a road on a hot day.

 

[Mt Spokane Photography]

Thanks dunbar...I neglected to mention that I use a cable remote. I pretty much take every precaution I can to keep my camera as still as possible. More to the point, though, was that I was wondering if this kind of non-sharpness was due to motion blur or just not being focused in the right area. To me, it looks like slight motion blur, but I'm not 100% for sure.

It does look like motion blur, I see no evidence of front or rear focus.
I have a cable remote too, sometimes, the cable sometimes transmits a twitch to the camera as I push the button, so a 2 or 5 sec delay helps damp out movement, as does hanging a weight on the under hook of the tripod. Wind can move the tripod / lens setup as well, it does not take much. I have a heavy duty tripod and head, but it can occasionally be a issue in wind, or just me and my remote cable release.(That took a while to figure out, since it had slack in the cable, but it still transmits a slight twitch.)

 

[EOBeav]

Thanks to everybody who weighed in on this. I believe I have found the culprit and it is me. Yes, a higher ISO and/or IS would have eliminated this motion blur. However, it wouldn't have happened in the first place had I taken the time to make sure everything was solid before I snapped the photo. That's what happens when you get in a hurry; you skip over some of the basics that you've been doing for a long time! All of the Canon 70-200 L's, regardless of aperture or IS, are really sharp, so that's why I was surprised to see this at first. I've used this same set up in creeks with exposure settings of .5 to a full second without any problems before.

In any event, I'll take care to keep everything still next time. Thanks again for the feedback.

 

[applecider]

Took your invitation to look at the larger pixel peeping image and for some reason that file looks pretty sharp. The bridge is in focus and there is little evidence of blur. Check it out and see if you see the same.

If someone else confirms this it would put the culprit in the post processing department.. maybe some kind of image depth or resolution downsizing. Or maybe noise reduction is loosing the detail.

 

[aprotosimaki]

Thanks to everybody who weighed in on this. I believe I have found the culprit and it is me. Yes, a higher ISO and/or IS would have eliminated this motion blur. However, it wouldn't have happened in the first place had I taken the time to make sure everything was solid before I snapped the photo. That's what happens when you get in a hurry; you skip over some of the basics that you've been doing for a long time! All of the Canon 70-200 L's, regardless of aperture or IS, are really sharp, so that's why I was surprised to see this at first. I've used this same set up in creeks with exposure settings of .5 to a full second without any problems before.

In any event, I'll take care to keep everything still next time. Thanks again for the feedback.

What was not solid?

 

[bdunbar79]

Took your invitation to look at the larger pixel peeping image and for some reason that file looks pretty sharp. The bridge is in focus and there is little evidence of blur. Check it out and see if you see the same.

If someone else confirms this it would put the culprit in the post processing department.. maybe some kind of image depth or resolution downsizing. Or maybe noise reduction is loosing the detail.

This happens to me ALL THE TIME. I will post-process and then export to jpeg and the file looks blurry. I'll then crop just a tad more, let's say off the top, then the file is sharp. This can also be seen with a blurry file, then you zoom in on it in your viewer and it is again razor sharp. I'm not an expert in resizing, downsampling, etc. and there has to be a very well known reason for this happening, and I cannot possibly be the only one that is seeing this.

 

[Mt Spokane Photography]

Took your invitation to look at the larger pixel peeping image and for some reason that file looks pretty sharp. The bridge is in focus and there is little evidence of blur. Check it out and see if you see the same.

If someone else confirms this it would put the culprit in the post processing department.. maybe some kind of image depth or resolution downsizing. Or maybe noise reduction is loosing the detail.

I looked at it as well, and its not up to expectations, it should be much sharper. If your images are not sharper, something might be wrong.

 

[EOBeav]

Took your invitation to look at the larger pixel peeping image and for some reason that file looks pretty sharp. The bridge is in focus and there is little evidence of blur. Check it out and see if you see the same.

If someone else confirms this it would put the culprit in the post processing department.. maybe some kind of image depth or resolution downsizing. Or maybe noise reduction is loosing the detail.

I looked at it as well, and its not up to expectations, it should be much sharper. If your images are not sharper, something might be wrong.

Agreed, this has nothing to do with image conversion. The full size image I posted was just that...a full size jpg export from LR, unedited.

Thankfully, I did a little test tonight and the lens is performing just fine. It was my own oversights that caused the blurriness.

 

[bdunbar79]

So what ended up being the problem?

 

[EOBeav]

So what ended up being the problem?

A few things come to mind:

• I was in a hurry and hit the shutter before I let the camera completely stop vibrating after moving it
• At least one of the legs was in some soft ground, so it wasn't 100% stable
• I didn't turn off the AF after getting the focal point where I wanted it, shaking the camera that much more

That bridge hasn't moved for 80 years or so, so it had to have been the camera. It was just a perfect storm of events caused from me not minding the store.

 

[J.R.]

So what ended up being the problem?

A few things come to mind:

• I was in a hurry and hit the shutter before I let the camera completely stop vibrating after moving it
• At least one of the legs was in some soft ground, so it wasn't 100% stable
• I didn't turn off the AF after getting the focal point where I wanted it, shaking the camera that much more

That bridge hasn't moved for 80 years or so, so it had to have been the camera. It was just a perfect storm of events caused from me not minding the store.

Good ... I was on the verge of suggesting there might have been an earthquake in the area!