Clouds - image and questions

How do you shoot sharp images of clouds? I've researched and found things like "always use a tripod" and use the "sunny 16" rule of thumb, but it seems so far to be impossible for me to get clouds that look like they look in the images posted on NPN as far as sharpness and just not being blurry and blobby.

I think the clouds in this image (which has no saturation, levels, curves, or any other changes like that applied) are blurry and blobby, right? The reason I didn't post this in the Gallery and ask the questions is because maybe they are just too blurry and blobby to post there.

My question is a general question about clouds, but for this image the techs are:

Canon EOS REBEL T2i
EF-S55-250mm f/4-5.6 IS
9/6/2011 – 7:57:06 PM
1/250 sec
Aperture priority
f/5.6
ISO 400
Focal length 55.0 mm

Your chosen shutter speed of 1/250 is certainly more than enough to freeze clouds and render them sharp. Your image actually appears pretty sharp overall (considering it would still be sharpened for web usage), but it appears that you severely clipped the red channel, rendering the reds blown out and this can make it appear somewhat unsharp. If your camera has an RGB histogram, check that after your shot and adjust as necessary to make sure the red channel isn't clipped. I might also suggest a lower ISO, but I'm picky about that because of my camera's LOUSY higher ISO capability.

How sharp can clouds expected to be? Of course, there is a difference between clouds rendered in motion by very long exposure, and clouds rendered "sharply" by short exposures. But in the end, I don't think that you can expect clouds to be pin sharp. They're just a bunch of water droplets.

Basil is right. The next time you find a fog bank, you'll see why.

Barbara, I agree with the comments so far. Keep in mind too that the clouds are usually miles and miles away (perhaps) and just knowing that the clouds are not static but constantly moving vapor. and at those distances, depth of field issues, I don't think you can expect tack sharp clouds under most circumstances. I would even say that the clouds in your sample image look pretty good. Perhaps you notice more because in this case the clouds ARE the subject, where as most times the clouds are secondary elements.
Good question, but I think your example looks good.

Lon

When clouds are the main subject, it can be difficult to get them looking sharp, even at faster shutter times. This is due in part to the very dynamic nature of clouds and also that winds aloft may have a much higher velocity than the wind close to the surface.

When I am photographing landscapes that include clouds, I am more concerned with proper exposure than I am with any movement of them. Someone viewing an image with clouds will accept the apparent movement because they know clouds move and change, but they likely won't accept poor exposure.

Your image looks pretty good to my eye, Barbara.

--P

Barbara,

Check out Tony Kuyper's cloud sharpening Photoshop action: http://goodlight.us/writing/cloudsharpening/cloudsharpening-1.html. I have recently started using his actions and am pleased with the results of this particular one.

Hi Barbara,

I was just going to point out Tony's cloud sharpening action. But really the lack of "NPN Sharpness" doesn't have anything to do with the clouds. Part of it probably has to do with the sharpness of the lens itself, as most of the serious landscapes shooters here are using "L" series lenses. Some are even using Nikon lenses on Canon bodies because a particular model is sharp. However, I suspect that the real sharpness you are noticing is in the sharpening for web used by many here. Again, I would encourage you to check out Tony's action set. He has a "Sharpen for web" action which pretty much changed my life.

I also wonder, are you shooting RAW? If so, the files will need an initial sharpening when brought into Photoshop. Then an additional sharpening at the end for output to the web (different sharpening for print output). Hope that helps

Miles - I'll eat my hat right on the spot if the sharpness difference between a good and a very good lens has any meaningful influence on the sharpness of clouds shown in a web-sized image. I agree with your other points, though.

No need to eat your hat, Basil. :) Totally agree that at a small size like this, the lens won't matter a hoot. I'm assuming that Barbara was talking about cloud sharpness in general, not just this particular shot at this particular size.

The other thing to consider, at least for this shot, is that pretty much all consumer lenses focus the reds at a different plane than the rest of the spectrum.

If you ever get to use an 8X10 you will see what I mean. Put a red object on the same plane as other colors and then focus on each of them. The red will require a different focus point than the other colors. This can be enough on a shallow depth of field to make the red look out of focus, as in your cloud shot.

I don't think it has been mentioned yet, but if you are using auto-focus, your system may have difficulty locking focus on clouds. Manual focusing may be the way to go, but then again it can be difficult. Try Live View and manual focus on a tripod to make sure you know that you are indeed focusing on the clouds. At least this will narrow down and eliminate some variables in blurred clouds.