70-200 f4 - image quality

[corey_gardner1]

I've had a 70-200 f4 lens for almost two weeks and I have a question

for those of you that have used one. Coming straight out of the

camera there are alot of soft images at f4. It seems that I can clear

this up somewhat in post processing but it seems softer than I

expected, softer than other lenses I have. The reason I ask this is

that I have nothing to compare it to and have until Tuesday to

exchange it at B&H. Would you evaluate sharpness or image quality of

a lens before post processing or after? Are your images from this

lens sharp straight out of the camera? Thanks in advance for your

responses.

[gdanmitchell]

I get very sharp images from this lens but I _always_ apply at least some sharpening in

Photoshop. You won't get the maximum quality out of DSLR images if you don't sharpen.

 

I do have to admit that I rarely shoot with my lenses all the way open. I'm much more likely to

shoot at f/5.6-f/11 with this lens.

 

Can you post images from this lens at f/4 and perhaps other apertures?

 

Also, what do you see after applying sharpening?

[corey_gardner1]

Here is one image. Shutter speed is over 1000 and taken in brighter light so camera shake shouldn't be an issue.<div></div>

[corey_gardner1]

And a second image. This one is cropped and shows what I'm concerned about. All of these are straight out of the camera, no post processing at all.<div></div>

[gluteal cleft]

I have the f/2.8 version, so take my words with a grain of salt. I haven't used the f/4.0 version, but I take it that it's as sharp wide-open as the f/2.8 is wide-open. If that's the case, then the two photos posted are somewhat acceptable, but seem like they still may not up to the capabilities of the lens.

 

If your images come out soft, you may want to look into whether the focus is accurate. DOF is not great at f/4.0, even at 70mm if you're shooting relatively close, and if your focus isn't on, then so much for sharpness.

[corey_gardner1]

Above images are both at f4. I want to be able to use the lens wide open for limited DOF as I usually take pictures of people.

[yakim_peled1]

>> there are alot of soft images at f4......softer than other lenses I have.

 

I had the same experience with the same lens about 5 years ago, when I was using film. As I had no chance of testing it properly, I don't know what was wrong. I suspect front/back focus.

 

Happy shooting,

Yakim.

[acedigital]

I have the 70-200 2.8L - there are a lot of instances where you need to apply sharpening - here is one click of sharpening in Picassa applied to your photo, seems acceptable to me. Remember with digital, YOU are the darkroom!<div></div>

[ken munn]

It looks soft to me, as soft as a cheap & nasty consumer lens.

 

Do other lenses on that body give poor results? If so, suspect a focussing problem with the

camera. If not, then the lens is a dog.

 

Yes, you should expect to sharpen in post-processing, but you need something there to start

with and this lens/body is not giving you much to work with.

 

As time is running out, I'd ask for a replacement straight away.

[PuppyDigs]

I had a 70-200 4L that was blurry only on the left side. Canon charged me $150 to fix it. It's

the only defective lens I've ever had, and I've owned a lot of lenses. I shoot most tele optics

wide open for narrow DOF so I expect them to be tack sharp. The point is sh!t happens,

although I'm sure most of these lenses are great.

[kai_griffin]

I've never had images this soft from my 70-200 f/4 wide open (been using it nearly 4 years now), so I'd definitely lean towards suggesting some kind of autofocus problem there. IMHO, Mark's post-sharpened version above looks atrociously over-sharpened and harsh... and in any case 70-200/4 images should simply not be this soft straight out of the camera, even wide open.

[pjmeade]

I have had the 70-200/f4 for a year now and I've been very satisfied with the results. However, I always apply some sharpening to the image.

 

This is a full frame shot at f4 and had some sharpening applied: -

 

http://www.photo.net/photo/3995532

 

I like to keep the shutter speed as high as I can.

 

Hope this helps.

 

P

[ben_jamin]

I don't know what camera you are using but straight out of the camera without any post processing they should NOT be that soft, 1/1000s should be fast enough to freeze action and stop camera shake unless you yank it violently, I think your copy is either front or back focus, they're way too soft and pretty bad....even kit lens are sharper than that at wide opened!

[delwyn_ching]

I've had this lens for over 6 months now and haven't encountered soft photos yet. Maybe it's your focusing scheme on your camera that's not able to lock onto the subject but is to the backgound or foreground. good luck

[edgreene]

The EOS 70-200 f/4 ``L`` is <i>generally</i> accepted to be the very best performing of the medium ``L`` class zooms. The <i><b>very best</b></i>, sharper still than the superb EOS 70-200 f/2.8.<p>Yours must be a manufacturing exception. <br>Send it back.

[sidaths]

I'll keep this short -- I use the 70-200 f/4 on a 350D and have never taken any shots that blurry at f/4 let alone at 1/1000s.

 

Replace it while you can!

[corey_gardner1]

Thanks for the responses. Camera is a 20D. I'll be swapping it out today for another copy. If the problem is still there I'll know it's something else.

[KenPapai]

I highly doubt the f4L is sharper than the 2.8L at any focal length. Having said that I've never used an f/4L telephoto lens.

 

I shoot the 70-200 2.8L at f/2.8 very often for portraits of people. It is extremely sharp at f/2.8 provided your technique is good: tripod, shutter speed, MLU, focus point selection, and your software post-processing skills are at least intermediate level. (Cameras used by me include 10S, 10D, 20D, XT, and 5D)

[KenPapai]

I forgot to add -- part of your reportoire undoubtedly should include the lens hood (ALWAYS use the lens hood) and a high quality filter (UV or polarizer depending on the situation). The filter use is up to you and often debated and largely depends on your shooting environment. (it's stupid to use a filter indoors unless kids are running around like animals with party cake or drunks are spraying beer or bubbly ;)

 

Bottom Line: Image quality from your lens-camera combo depends 80% on the user and just 20% on the lens.

[gdanmitchell]

<p>Unless those two shots are 100% crops, they do seem soft. If they<i> are</i> 100%

crops (e.g. - a small portion of a much larger full image) then the sharpness is not great,

but might not be too far out of line for f/4.</p>

 

<p>I agree with the earlier writer who suggested that the sharpened example posted by

someone else is very overdone. You would not want to have to resort to that sort of

sharpening to get decent images. (Note the halo effect around the lines.)</p>

 

<p>One possibility has been mentioned - that your lens is front- or back-focusing. If so, I

think we would see either the sand right behind the boy's feet or right in front appearing

in focus. My eyes tell me that the camera/lens combo <i>may</i> be focusing a bit

behind the intended focus point, but that the image isn't really sharp even there.</p>

 

<p>Another possibility is that some blur was created by handholding the long lens.

(200mm is equivalent to 320mm on a crop sensor camera.) However, your 1/1000

shutter speed would make it likely that you would get at least <i>some</i> sharp

images.</p>

 

<p>Some things to try as you work to narrow down the possibilities:</p>

 

<ul>

<li>Put the camera on a tripod and use a remote shutter switch or a timer and lock up the

mirror. This will eliminate the (unlikely) possibility that the problem was simply camera

motion.</li>

<li>Try shooting a test subject (using the setup described above) at different apertures.

I believe that f/8 or so should be in the sharpest range for this lens.</li>

<li>There are a few ways to check for front/back-focusing. One is to put the camera on

the tripod, let it AF focus the lens, turn AF off to take a photo, and then take a couple

more photos manually focused <i>slightly</i> closer and further than the automatic

setting.</li>

</ul>

 

<p>It isn't impossible that some of these factors could have caused the problem, but I

also wouldn't be surprised if your lens needs some adjusting.</p>

 

Dan

[jan_thomas1]

Corey, are you doing the focus/lock/recompose dance?

[ben_jamin]

like someone said, before you returning it, test that lens on a tripod first, use stationary stuff like a doll or puppet in well lit area, put a can of soda or something next to your main object slightly infront and behind, take a few shots ON the tripod and post back some result, if they're still soft like that...then don't bother, ship it straight back to where you bought it from.

[corey_gardner1]

I took about 500 images with the lens over a week. The first example above is not cropped at all. The second one is not a 100% crop but I did pull out that portion of the image to show what I was referring to. The softness is apparent even with a passing glance (no pixel peeping). Sharpening didn't really fix either of the above images.

 

Jan - I struggled with tracking a moving subject (kids). I did focus/recompose quite a bit. Again, this is a 20D. If I put the camera in AI Servo mode, the camera wanted to use the center focusing point. Changing the focus points manually worked but I had to then keep the chosen point on the subject. If I switched to AI Focus mode it took the camera a bit of time to "catch up" with the subject so I missed shots. For some reason I struggled tracking a moving subject so I'll have to look into this technique more. If you have any suggestions, let me know.

 

I already have a return code from B&H so either way I'm swapping it out as I have little time left. Now I have to decide between the f4 again or jump up to the 2.8 non-IS version. Would the 2.8 version be better for action photography (focus faster)?

[digitmstr]

The problem in your image is FOCUS. <a href=http://www.photo.net/photo/2772909>This image</a> (and every image inthat folder) was shot with that lens wide open, mounted on a 10D in JPG mode, minimal post (to adjust & resize for web display). Camera in Manual exposure and manual WB.

<p>

You can't post-process an OOF image as it would only create a weird glob of pixel-sharpened OOF areas. It seems your subject was moving and that makes it a bit harder to lock. It's actually easier to lock onto a runner for example than an erratically moving subject. Also, it helps greatly to have the AF on the (*) button as opposed onto the shutter button. That way you can lock focus indipendently (and on the fly).

[pbizarro]

I also think that this is a focus technique problem. Learn how to focus correctly, and your problems will go away.