Crystal clear sharp photos

[pasoviennese]

Hi everyone,

I've been taking photos with my Canon 30D with a Tamron 18-270mm lens for a couple of month now. One thing that's been kind of troubling me is getting crystal clear sharp images. I'm not sure if it's a build in "defect" of the lens, but the photos isn't as sharp as I hope. Or maybe I'm simply asking for too much! I'm talking about at 100% view, the contrast edge isn't as sharp as knife cut.

Let me show you a photo straight from the camera, zoom in to 100% and you'll see what i mean.


David + Lauren 01 by *jamesqwang on deviantART

Photo was taken at 270mm, 1/125, f6.3 and iso 400.

Please given some tips on getting sharper photos. And also, how important is sharpness when it comes to whether a shot is one of the top shot or an average one. Is the one I took alright?

[sybren]

With 1/125 second at 270mm it's no wonder things aren't sharp. There are many ways in which you could improve this photo. First of all, get more light so that you can get a fast shutter speed - some strobes would probably help a lot. As for the composition -- what's the black stuff in the background?

[pasoviennese]

Originally Posted by sybren

With 1/125 second at 270mm it's no wonder things aren't sharp. There are many ways in which you could improve this photo. First of all, get more light so that you can get a fast shutter speed - some strobes would probably help a lot. As for the composition -- what's the black stuff in the background?

Sorry, forgot to add that the lens had a 4 stop IS.

The black stuff in the back ground is advertisement banners.

The black box thing on the white rail is a video camera. Pretty cool stuff they use to track ballroom dancers as they dance across the floor!

Also, flash is not allowed at dance competitions.

[BCampbell]

1/125 is not quite fast enough to really freeze motion. Remember that stabilization will not help with action, only with vibrations from camera shake -- so it's great for still life but don't rely on it to stop movement for you.

f6.3 is probably not the best aperture for sharpness with this lens. You will probably want to close it down to f/8 or so.

I would say in this case it's probably down to the lighting and the lens itself. You generally have to pay a pretty hefty premium for glass that delivers super sharp results. I think that by trying to compromise with a relatively inexpensive lens that has such a wide range of focal lengths, you're sacrificing a little image clarity.

dpreview has a pretty good revew of that lens where they talk about sharpness, it looks like this lens is best in the mid focal lengths.

So, here you will want to stop down, shoot faster, and maybe think about other lens choices.

Do you have photos you're comparing to, so we can see what you're looking for?

[sybren]

Without flash and without having more light, I'm afraid that the only way to get sharper results is to get faster glass...

[natek313]

I think you should also keep in mind that at 100%, nothing is going to be razor sharp. I've used L glass, and the results are still not razor sharp at 100%. I think to expect that is to be a little unrealistic. No offense.

[BCampbell]

Originally Posted by natek313

I think you should also keep in mind that at 100%, nothing is going to be razor sharp. I've used L glass, and the results are still not razor sharp at 100%. I think to expect that is to be a little unrealistic. No offense.

I was going to mention this too. People rarely view photos at 100%, especially at the distance from the screen to your face.

You can safely print at 150ppi (300ppi is preferred, but 150 works just fine). At that resolution, the 30D can print to 20x14. Nobody is going to view that size image from eight inches away unless they're scrutinizing it. If you're printing to 8x10, you can resize to 1500x1200 and run a light unsharp mask, and you will probably be happy for anything less than hanging in a gallery.

[dogwatch]

One of the more tried and proven techniques for determining whether or not you can successfully hand hold your camera and lens combination is to compare the reciprocal of your effective focal length with your shutter speed.

For instance, if your effective focal length is 250mm, you should seriously consider using a tripod or some other means of support for shutter speeds less than 1/250 sec.

Using the information you provided (270 mm with a shutter speed of 1/125), you should be using a shutter speed of not less than 1/250, and preferably higher ... 1/500 or more; the possibility of getting a shake free exposure using 1/125 sec is questionable unless you use other techniques to reduce or minimize the effects of camera/lens movement during exposure.

Since you are already up to an ISO of 400, your options come down to:

Using a tripod;
Increasing your ISO to get more speed which will result in more noise/grain;
Flash (maybe out of the question considering distance involved);

The support you use doesn't necessarily need to be a tripod. I routinely shoot wildlife photos with a 600 mm lens using a sturdy monopod. Monopods are extremely versatile; they are less cumbersome than a tripods, can be quickly set in place, and provide you with considerable flexibility.

Another point to consider ... does your telephoto (Tamron) have a built-in tripod collar?

If you try to mount longer camera/lens combinations using the camera tripod mounting screw, what results is an extremely front-heavy camera that is almost impossible to hold steady even with a tripod - the camera/lens combination needs to be supported somewhere near the center of balance for that particular camera/lens combination - that's where the tripod ring on the lens comes into play.

Hope this helps ...

Ed

[chl0e]

I don't know if this is a stupid suggestion but on my camera (sony a200) you can set the sharpness up by 3 stops so maybe that would help?

[kencaleno]

Originally Posted by natek313

I think you should also keep in mind that at 100%, nothing is going to be razor sharp. I've used L glass, and the results are still not razor sharp at 100%. I think to expect that is to be a little unrealistic. No offense.

When doing stock photography,agencies require tack-sharp images at 100%,and reviewers will reject images that are not tack sharp at 100%-You can get razor sharp images at 100% from kit lenses, once you understand how, never mind "L" glass. Ken