Canon 70-200mm f/4L IS Lens Quality

[disdat]

Hello all,

I have had my new lens (Canon 70-200mm f/4L IS) for just a week now, and today I tried some photo tests.

Photos taken at 4 focal lengths - 70mm, 100mm, 135mm, and 200mm
Each at f/4, f/6.3, f/8, and f/11

The first three focal length tests (I thought) were very good. But the shots taken at 200mm are very blurred and muddy. I even reshot to the same results.

I shut off IS, used a tripod, used a wireless remote, and enabled mirror lock.

Can someone take a look at these photos, and tell me if it is normal, or if my lens is bad??

http://picasaweb.google.com/splash.style/70200Test2

You can zoom into each photo with the little magnifying glass; and it might take google a few seconds to focus on the photo when zooming.

If you want to go straight to the 200mm shots, here are the four:
http://picasaweb.google.com/splash.style/70200Test2/photo#5183223880450124098
http://picasaweb.google.com/splash.style/70200Test2/photo#5183224279882082642
http://picasaweb.google.com/splash.style/70200Test2/photo#5183224559054956898
http://picasaweb.google.com/splash.style/70200Test2/photo#5183225001436588402

Thanks to anyone that might be able to help!!!

 

[Inconsequential]

Get a backfocusing chart and print it out.

http://focustestchart.com/focus21.pdf

Page 18


45 degrees to the page with center point AF where it says "focus here" take shots wide open.

Then post the result

 

[Kebabselector]

Doesn't look too good, however have you tried shooting outdoors rather than attempting to use it as a macro?

Depth of field close up at 200mm is very small. This might account for the poor quality

 

[ChrisA]

The problem is the way you did the test.

Have you calculated the expected depth of field for a 200mm lens at f/4.0 at this distance? It comes to something like 1/8th of an inch. In other words wrinkles in the test target, misalignment (lens axis not 90 degrees square to test target) or just a small error in focus will cause some blur.

At 15 feet distance your 200mm f/4 lens has a DOF of about thee inches. Even then it is hard to set up a good test.

Also lenses can be sharp at one distance and not at others. Yours is an "internal focusing" lens where the elements move relative to each other to change the focus. It maybe is not so sharp this close. Try it again at 30 feet, a more reasonable distance for a 200mm zoom.

If you work it out there is no way for a flat target to all be in focus at once. The corners are farther away from the lens than the center of the target. Some lenses are designed to correct for this. There are macro lenses designed for flat copy work but most lenses and all zooms are not even close to what they call "flat field". With most lenses the "plane" of focus is some kind of curved surface.

The best way to test a lens is to shoot a 3 dimensional subject at a "normal" distance. It really is not wonder that macro shots done with a telephoto zoom are soft. The 3D object will always have some part of it in focus even if not the part you intended.

The $20 bill is a good test subject if you are testing a macro lens. For yur lens look for some natural objects that have lots of detail

 

[disdat]

Excellent advice.

I will try shooting something more appropriate. I will post the results.

I will also check into the pdf you linked Concorde!

Thank you!

 

[disdat]

I have some new photos.

I went out this AM and took some outdoor shots, but since it is still "winter" here in New England, I was very uninspired. I wasn't thrilled with any of them.

But later, I got some shots at the birdfeeder/porch from our window. These are the kind of shots that I like to take, so it was a good opportunity for a test.

Zoomed in, they are just a tad on the blurry side, but I think that it is more user error, and the settings I chose. I tried to keep it at a high shutter because the birds are so fast, but I might need an even higher one.

All shots are hand held, IS enabled, Shutter Priority @ 1/160, ISO 100.

xxxx

Tell me what you think. Over all I think they look good, but again, I might not be seeing the flaws.

Thanks all!!!

 

[jbernie]

My unprofessional review... pics 1,3 & 4 are great, pic 2 is a little blergh but that is because of the position of the subject which you have no control over

Although I am looking into the lens you bought I haven't done enough research to know what to expect yet. This being said it appears as though the focus on the subject (bird) is very sharp and as a result the background is blurred which may or may not be an unexpected result.

 

[Edge100]

I'd say the pics look fairly sharp. Although you don't mention what aperture size you used, that lens should be sharp at F4. However, it would be good to indicate this to determine what depth of field to expect. You can see quite clearly in pic 1 that focus is very sharp on the blue jay's wing, but its face is a bit less sharp (also see the difference in sharpness between the middle of the birdhouse, and its distant and near edges...the middle is in much sharper focus than the edges, especially the near edge). I assume this is taken at 200mm F4 (i.e. very shallow DOF)?

All in all, I'd say you have a very good copy of a very good lens. I have the non-IS version, and it is equally sharp, though I sometimes wish I had IS (to save me from lugging my tripod around with me all the time).

 

[disdat]

Hello,

Thank you for your comments!

Edge100, the EXiF info can be read for each photo on the right side (more info) - most of the shots are f/4 (wide open). I had it on shutter priority 1/160 - not fast enough I think for birds.

Plus, someone else pointed out that the shots of the birds were through glass, so it would affect IQ. That could be part of my problem too.

Anyway, I have been researching and found that this lens does indeed have a problem with MFD (minimum focus distance) for focal lengths 135 - 200.

http://www.fredmiranda.com/forum/topic/617286

I am just starting to read through all the pages now, but it doesn't look like the non-IS is affected.

I think I am going to return the lens, and go back to the drawing board of deciding what I really want and need.

Thanks everyone for the great advice. I have learned a lot!

 

[jbernie]

I think I am going to return the lens, and go back to the drawing board of deciding what I really want and need.

Thanks everyone for the great advice. I have learned a lot!

Maybe hold out and see if Canon comes out with a recall/service requirement for the lens or even releases a v2. I read through the posts on the FredMiranda site, hard to say if the lenses are faulty, have a known (unpublished?) limit or some people are trying to do things the lens just isn't designed to do.

 

[disdat]

Maybe hold out and see if Canon comes out with a recall/service requirement for the lens or even releases a v2. I read through the posts on the FredMiranda site, hard to say if the lenses are faulty, have a known (unpublished?) limit or some people are trying to do things the lens just isn't designed to do.

If Canon does that, then I will consider the lens again. But I don't think it'll happen any time soon, considering the conversations started almost a year ago (in May 2007)

I just don't think I want to chance it, especially when I will probably use it at the 200mm end most of the time.

Why pay $1K for something that doesn't blow my socks off...and this lens at 135mm and under is superb. I couldn't believe how good it looked. But it does me no good if I am using it @200mm.

Know what I mean?

That doesn't mean that you shouldn't still consider it. For me, I think I am looking for more of a "nature" lens. I am still considering the 200mm prime (f/2.8) (small and easy to attach a 1.4x) and the 300mm prime (f/4) - I love prime lenses.

Make sure you take a look at the dpreview conversations (linked in the forum post over at FMReviews) - I am still wading through them, but it is interesting reading.

 

[davem7]

That's probably a good call - if you're not happy with the lens then it's definitely worth sending back.

My personal preference would be to go with the 100-400 which I saw you were considering in your original thread. It's an excellent lens and ideally suited to nature photography because of the range and very good IQ, even wide open.

If you're going to go with a prime, I'd get the 300 f/4L + 1.4TC or even the 400 f/5.6. In my mind the 200L isn't long enough to capture the birds at a distance without significant cropping.

 

[disdat]

That's probably a good call - if you're not happy with the lens then it's definitely worth sending back.

My personal preference would be to go with the 100-400 which I saw you were considering in your original thread. It's an excellent lens and ideally suited to nature photography because of the range and very good IQ, even wide open.

If you're going to go with a prime, I'd get the 300 f/4L + 1.4TC or even the 400 f/5.6. In my mind the 200L isn't long enough to capture the birds at a distance without significant cropping.

Thanks Dave! I appreciate your feedback! I see you have the 100-400 lens. I have heard many good things about it, but I will have to do more checking. As if I haven't researched a million times already!

yeah, I have a feeling I will be in the same boat with the 200mm prime. LOL. Not happy with the range.

I am considering the 100-400, and for sure the 300mm. I know both lenses are monsters, but I think I can handle it, especially if I am getting good shots from them. It will be worth any arm pain!

I just don't want to keep sending lenses back. I hate doing that.

 

[davem7]

Either of the lenses are going to give excellent results. The 100-400 isn't too bad to handle once you've gone out a few times with it. One more tip would be to invest in a monopod if you do a lot of hand-held shooting. With the IS on it's almost like having a tripod and your shots tend to come out a lot sharper, with the added bonus that your arm doesn't ache as much

 

[HomeingPigeon]

Those birds look amazing. Love the clarity. If I had the money right now I would be buying that same lens.

 

[princealfie]

why not shoot with a wide angle lens instead?

 

[disdat]

Just a quick update. I returned the 70-200mm f/4L IS lens safe and sound to B&H.

And today I placed my order for the Canon 300mm f/4L IS prime. It will be here on Friday! Yay!

B&H was out of stock, so I ordered from Adorama. I also ordered a Hoya 72mm UV (Ultra Violet) Super Multi Coated Glass Filter:
http://www.adorama.com/HY72UVSM.html

Thanks all for your advice and help!

 

[Kebabselector]

Enjoy the 300mm it is a superb lens (though I didn't bother with the filter).

Don't worry about the clunking sound, that's the 1st gen IS motor.

 

[disdat]

Enjoy the 300mm it is a superb lens (though I didn't bother with the filter).

Don't worry about the clunking sound, that's the 1st gen IS motor.

Yeah, I am not much of a UV filter user myself, but I figured I should with a lens like this.

and I have heard about the loud IS motor!!

 

[disdat]

One last update, the 300mm f/4 IS lens came today. I love it. It is very heavy, but I will get used to it.

I found the IS to be actually very quiet, compared to the 70-200 f/4L IS that I just returned.

But so far, the lens rocks!! I am really happy with my choice!