How to increase sharpness?

[Thaash]

I recently bought a Sigma 17-70 2.8-4.5 DC. THis model has no IS.
I use it with my EOS 50D.


I made the following shot with it (pic was resized, no PS at all) :

In 100% view:

I did not use a tripod. Shot was made with 70mm, ISO 400, F/10 1/100 shutter speed.

How can I get the image sharper with the camera when I shoot next time?

 

[Silvius Brabo]

Try a faster shutter speed for starters, 1/100 is pretty slow for daylight pictures. With the faster shutter speed you can stop the ISO down easily to 200 or 100. And the aperture can maybe be bumped down to f/8 or even f/5.6 as there isn't really any shadow (going by the sunny f/16 rule)

 

[JG_Coleman]

I did not use a tripod. Shot was made with 70mm, ISO 400, F/10 1/100 shutter speed.

How can I get the image sharper with the camera when I shoot next time?

Well, not to point out the obvious or anything... but might I recommend using a tripod next time?

You can use a larger aperture to improve shutter speeds, and you will probably get better hand-held results... but you'll also lose depth-of-field. You could also bump the ISO higher to improve shutter speeds... but the higher you go, the more your overall image quality will be degraded by noise.

As it is, though, the basic rule for minimum hand-held shutter speed (1/focal length) isn't being met with this shot. Your EOS 50D has crop factor of 1.6x... meaning that at 70mm with your Sigma, your 35mm equivalent focal length is 112mm. So, a shutter speed of no less than 1/112 sec is necessary for a moderately sharp hand-held shot. Even still, that's just a basic guideline. You'd probably need at least 1/200 sec for better results... and the faster the better.

But assuming that...

A) you intentionally wanted the depth-of-field offered by f/10, and
B) you don't want to go higher than ISO 400 (I wouldn't even go that high unless absolutely necessary)

...your best bet is to bust out that trusty tripod, or at least try to stabilize the camera on a rock or something. You'll always get the sharpest results with a tripod.

 

[pgriz]

The quick way of figuring out whether the sharpness (or lack of) is due to the lens or you, is to put the camera on a tripod (that reduces camera shake), use a delayed timer on shutter or a remote shutter (reduces camera shake as well), focus manually on your chosen target (avoiding issues with the camera's autofocus), and use live-view magnified (for precise placement of your focus point). Shoot one shot wide open, and another shot at f/8 or f/11. There should be little difference between the two at the center of the field. These two shots will show you the maximum sharpness you can get out of your lens.

Now if your hand-held shots are nowhere near as sharp as these, then it's probably you and your shooting technique. Otherwise, if you're not getting the expected amount of sharpness even when you did all the things in the first paragraph, then it's probably the lens.

Another contribution to loss of sharpness, beyond the usual suspect of hand-shake, is reliance on the autofocus of your camera. Some cameras either front-focus or back-focus (the actual focus point is either in front of, or behind, the point you think it is focusing on), and that has to be fixed by adjusting the camera by the manufacturer. If you are using general autofocus, it can select something that is NOT your chosen point. So for the sharpest pictures, you generally have to do the focus selection manually.

One more thing - if you are using a UV filter, get rid of it when you're testing for sharpness. I've already found out the hard way that the quickest way of getting a $1,600 lens to perform like a $100 lens is to put a cheap UV filter in front of it.

And to reinforce JG Coleman's suggestion - use a tripod! It's the cheapest way of getting sharp, well-composed shots. The greatest improvement in image quality in my own case came when I started to routinely carry my tripod around everywhere. Bryan Peterson, whose books are almost bibles for photographers, has said in his book "Learning to see creatively", that of the hundreds of photographs in his book, only a few were taken hand-held. I also belong to a large photo club, and virtually all the best photographers in that group routinely use tripods. The wannabees rarely do, and it shows up in the competitions.

 

[syphlix]

how to get sharper image:
- faster shutter speed
- more stabilization (tripod)
- focus on the right place (at f/10 shouldn't have a problem)

 

[Thaash]

Ty for all the comments.

Made another try with increased shutter speed: 1/250 and 4.5 aperture. Lens is still my $200 Sigma 17-70.

Used Flash here but no tripod again.

Thats the result:

Here in 100% view:

I think it turned out sharper than my previous shot. What do you think? Should I expect something sharper or thats the max with a $200 lens?

 

[DirtyDFeckers]

Try a faster shutter speed for starters, 1/100 is pretty slow for daylight pictures. With the faster shutter speed you can stop the ISO down easily to 200 or 100. And the aperture can maybe be bumped down to f/8 or even f/5.6 as there isn't really any shadow (going by the sunny f/16 rule)

Seriously? So let me get this straight.... speeding up your shutter allows a lower ISO? I doubt that.... The faster your shutter, the larger aperture you need, or higher ISO(a.k.a. light sensitivity) to produce a decent exposure. At least know what you are talking about before you give advice to others.

 

[reznap]

Do you have any other lenses to compare? Maybe a prime?

Doesn't look too bad, I think you're seeing the limits of the lens though.

 

[Sonoma]

I have the same lens and have found it to be soft at both ends of the focal length.

I shot this hand held the other day just fooling around; bounced the flash off the ceiling......

1/200 f/7.1 ISO 200 at 44mm

Not much depth of field, but I was only inches away. That that is in focus seems very sharp. I may sell or trade this lens for something just a little better!:mrgreen:

Good luck!

 

[burgo]

I think you are getting mixed messages in this thread about shutter speeds & ISO's etc.

think of it this way:
Shutter speed controls ambient light
Aperture the light from your subject
ISO light sensitivity higher if dark, lower if light.

You don't need high shutter speeds on a still object. You need your aperture set to capture the object perfect (with or without fill flash) and a shutter speed/ISO that does not allow ambient light to blow out your image (like skies etc.

If you zoom in tight it will blur around the edges. That is a depth of field issue and to do with your lens. Now if you want to sharpen your image shoot it in raw and use your raw processing software to increase the sharpness. But remember this can add noise as well if you go too hard. So then you use a program like neat image to fix up the noise (grain).

Most of all keep practising and trying different settings. make a note of how successful you are and remember the settings you used that worked.

 

[GooniesNeverSayDie11]

I think you are pixel peeping on a cheap lens and expecting miracles. You can try all of those things like a tripod and live view/mirror lock up, cable release etc etc. But if you can't take a shot that you are happy with at that focal length in daylight hand held, you either need to work more on your technique and or invest in a better lens.
Check out this site and you can plug in lenses. http://www.the-digital-picture.com/...p=412&CameraComp=453&SampleComp=0&FLI=5&API=5

They only have the OS version of this lens, but even on that one it looks like F8 is the sharpest aperture but none of them are razer sharp by any means. I would just sharpen a bit in post and call it a day.

 

[DerekSalem]

I did not use a tripod. Shot was made with 70mm, ISO 400, F/10 1/100 shutter speed.

How can I get the image sharper with the camera when I shoot next time?

Well, not to point out the obvious or anything... but might I recommend using a tripod next time?

You can use a larger aperture to improve shutter speeds, and you will probably get better hand-held results... but you'll also lose depth-of-field. You could also bump the ISO higher to improve shutter speeds... but the higher you go, the more your overall image quality will be degraded by noise.

As it is, though, the basic rule for minimum hand-held shutter speed (1/focal length) isn't being met with this shot. Your EOS 50D has crop factor of 1.6x... meaning that at 70mm with your Sigma, your 35mm equivalent focal length is 112mm. So, a shutter speed of no less than 1/112 sec is necessary for a moderately sharp hand-held shot. Even still, that's just a basic guideline. You'd probably need at least 1/200 sec for better results... and the faster the better.

But assuming that...

A) you intentionally wanted the depth-of-field offered by f/10, and
B) you don't want to go higher than ISO 400 (I wouldn't even go that high unless absolutely necessary)

...your best bet is to bust out that trusty tripod, or at least try to stabilize the camera on a rock or something. You'll always get the sharpest results with a tripod.

Not quite sure why you wouldn't wanted to go over ISO400...on the 40D he should be able to easily use ISO800 without any noticeable noise (or at least not enough to warrant the lack of use) and would probably be fine noise-wise at ISO1600.

As for the rest...definitely lower the f/stop (increase the aperture size). No real reason to use f/10 in this case. f/5.6 would probably be completely fine (getting enough of a depth of field to get a majority of the shot in focus but nicely blend out the background). That would give you almost 2 full stops of light (meaning you could have your shutter speed at 1/400 at ISO400 or 1/200 and ISO200). Would definitely help you get rid of the motion blur.

 

[mooney101]

I great tip when shooting is to have your camera set on rapid release and hold down the trigger and take 3-5 shots of each subject. One of those will come out sharp almost Evey time.

 

[JG_Coleman]

Not quite sure why you wouldn't wanted to go over ISO400...on the 40D he should be able to easily use ISO800 without any noticeable noise (or at least not enough to warrant the lack of use) and would probably be fine noise-wise at ISO1600.

Noise is the bane of my photographic existence, Derek... and it's very noticeable to me at 1:1 inspection. I'll admit that this may qualify as nit-picking my own work... but I'm not just trying to get a good shot, I'm trying to get a great shot. I'll concede that ISOs of 800, even 1600, are usually a safe bet for making a decent photograph, especially if you're only making small prints with them. I, personally, don't budge any higher than my native ISO of 200 unless I really feel that there's no other way to achieve an appropriate shutter speed. And since I shoot on a tripod about 90% of the time, I rarely have to resort to ISO increases.

The less I have to pay attention to the noise sliders in Lightroom, the better...

 

[peanut170]

I think you are pixel peeping on a cheap lens and expecting miracles. You can try all of those things like a tripod and live view/mirror lock up, cable release etc etc. But if you can't take a shot that you are happy with at that focal length in daylight hand held, you either need to work more on your technique and or invest in a better lens.
Check out this site and you can plug in lenses. Sigma 17-70mm f/2.8-4 DC Macro OS Lens - Canon EF 16-35mm f/2.8 L II USM Lens Comparison - ISO 12233 Resolution Chart Results

They only have the OS version of this lens, but even on that one it looks like F8 is the sharpest aperture but none of them are razer sharp by any means. I would just sharpen a bit in post and call it a day.

This could be a pretty helpful chart if i could tell what the hell was going on. lol. It all looks the same to me.