17-40 mm f4L - did I get a bad copy :-(

[tommykjensen]

Just did some tests of this lens and I think I got a bad copy :cry:

Tripod and flash used, ISO 100, AV aperture 4.0. Distance from middle statue and front of lens 75 cm.

First shot at 40 mm, shutter 0,5 sec.
Full size image (http://photo.klein-jensen.dk/public/ef1740test1.jpg)
Afpoint used
http://photo.klein-jensen.dk/public/ef1740test1afpoint.jpg
100% crop
http://photo.klein-jensen.dk/public/ef1740test1crop.jpg


Second shot at 17 mm, shutter 1/4 this is baaad
Full size image (http://photo.klein-jensen.dk/public/ef1740test2.jpg)
Afpoint used
http://photo.klein-jensen.dk/public/ef1740test2afpoint.jpg
100% crop
http://photo.klein-jensen.dk/public/ef1740test2crop.jpg

[snibbetsj]

Did you use mirror lockup on these shots? That may be a problem.


Jeff

[booggerg]

You are obviously focused on the door handle instead of gollum in the 17mm pic. Did you check your focus? Are you complaining about the 40mm image too? That looks a lot like my 17-40 and I don't like how it looks.

[Persian-Rice]

Not sure, but I have heard the 17-40 does not perform quite as nice with the 20D as it does with other bodies. Not sure if that correct or not.

[tommykjensen]

Did you use mirror lockup on these shots? That may be a problem.

No but I held the tripod tight against the floor while gently pressing the shutter.


You are obviously focused on the door handle instead of gollum in the 17mm pic. Did you check your focus? Are you complaining about the 40mm image too? That looks a lot like my 17-40 and I don't like how it looks.

No look at the image with the AF point high lightet. On both images focus is on the middle status where the red square is located. The 40 mm images is ok, should have mentioned that.


Not sure, but I have heard the 17-40 does not perform quite as nice with the 20D as it does with other bodies. Not sure if that correct or not.
I sure hope not :(

[DeeplyDigital]

For how long have you had this lens?

J.
-

[tommykjensen]

For how long have you had this lens?


1 month but I have not had time to test it properly until now.

[Pekka]

My first 17-40 was a bad one. The next one was almost perfect. Don't give up - it is a great little lens - if you can't get it replaced get it repaired/adjusted.

If you could try the one you have on Mark II you would know for sure if it is the lens.

[Cadwell]

Tommy, I don't understand why you are testing the lens for optical quality using really low shutter speeds. Surely that's just inviting camera shake and other vibration to adversely affect the image regardless of how stable you think you have the camera?

What happens if you run the camera with a higher shutter speed to eliminate that source of error?

[DeeplyDigital]

Test some more. In my opinion the 17-40 is somehow very
light sensitive and because it is so fast focussing it is also
very fast unfocussing. But as you say, maybe it isn't 100% :(

J.
-

[DamienB]

Pretty classic 10D/20D misfocus evident on the second shot - try again. One reason why I won't touch either body with a bargepole...

[tommykjensen]

Tommy, I don't understand why you are testing the lens for optical quality using really low shutter speeds. Surely that's just inviting camera shake and other vibration to adversely affect the image regardless of how stable you think you have the camera?

What happens if you run the camera with a higher shutter speed to eliminate that source of error?

But I used tripod for that same reason and the first image which is ok used a longer shutter speed than the second one which is not ok.

Yes I should probably test it in normal daylight too.

Shot one more test (http://photo.klein-jensen.dk/public/ef1740test3.jpg), bumped iso to 1600 and got shutter 1/60 but I don't think it is any better.

[Cadwell]

Shot one more test (http://photo.klein-jensen.dk/public/ef1740test3.jpg), bumped iso to 1600 and got shutter 1/60 but I don't think it is any better.

It's very hard to tell with the noise. I do think it's quite a bit better though.

[tommykjensen]

I will do more testing tomorrow in daylight.

[daveh]

I think the faster test looks much better - just noisy.

Maybe you're better at holding a tripod than I am, but I have to use a cable release or the self-timer in a situation like that to get consistent shots.

Also, you've got a fairly low contrast subject, a slow lens and not a lot of light. You might just be on the edge of the AF system anyway.

[tommykjensen]

Ok last test. I replaced one of the objects with one with more colors on it. Turned more light on, set iso back at 100, used mirror lockup and shutter 1/5.

http://photo.klein-jensen.dk/public/ef1740test4.jpg

So if the lens is ok afterall then what could be the problem with the photos I shot this weekend (http://photography-on-the.net/forum/showthread.php?t=47405&highlight=)

[Molydood]

Tommy, is it worth doing the same test with your 50mm for comparison?
I still reckon there is a problem there, but it could be due to the low light focus, and perhaps doing the same shot using the 50 on the same aperture setting is a worthwhile exercise to narrow down the problem, if indeed you still think there is one.
Martin

[evilenglishman]

these look like the same issues i was having with the 20D/17-40 combo.
I sent the body back as i know for a fact there is nothing wrong with my copy of the lens.

see if you can try it on a different camera.

[booggerg]

My first 17-40 was a bad one. The next one was almost perfect. Don't give up - it is a great little lens - if you can't get it replaced get it repaired/adjusted.

If you could try the one you have on Mark II you would know for sure if it is the lens.

What kind of symptoms did you find on your's?

[jyrgen]

Tommy, looking at your horseshow photos, it really seems that you may have a bad lens (or camera). But for your inhouse testing strategy I suggest using considerably higher shutter speeds to eliminate any shake issues. I mean, since you use flash anyway, why not use at least 1/200 shutter speed?

[tommykjensen]

Tommy, looking at your horseshow photos, it really seems that you may have a bad lens (or camera). But for your inhouse testing strategy I suggest using considerably higher shutter speeds to eliminate any shake issues. I mean, since you use flash anyway, why not use at least 1/200 shutter speed?

I will do more tests later today hopefully with daylight.

[tommykjensen]

Daylight was over when I got back from work.

So I did a new test. Yesterday I had to use the internal flash because the batteries on my 550 ex was dead.

Following testshot was shot with a shutter of 1/125 using the ex550 flash and I have a halogen lamp pointing directly at the subject.

I think it looks better than yesterday but I still need to do some daylight testing of objects from a longer distance.

http://photo.klein-jensen.dk/public/ef1740test5.jpg

[tommykjensen]

Ok did a new test today with daylight and as a result faster shutter times. I still used a tripod and I tested it against efs 18-55 mm.

Full size shot with the 17-40 mm, ISO 100, f4, 1/500 at 17 mm
http://photo.klein-jensen.dk/public/ef1740at17mm.jpg

100% crop
http://photo.klein-jensen.dk/public/ef1740at17mmcrop.jpg


Full size shot with the 18-55 mm, ISO 100, f4, 1/400 at 18 mm
http://photo.klein-jensen.dk/public/efs1855at18mm.jpg

100% crop
http://photo.klein-jensen.dk/public/efs1855at18mmcrop.jpg

What do You think, is my lens ok afterall?

[Cadwell]

What do You think, is my lens ok afterall?

The 17-40L crop is MUCH sharper than the one from the 18-50. Looks good to me, especially for a lens wide open. The contrast is also better.

[paulo35]

I think this lens is much overrated it is not sharp frankly and on a shot for shot test with equivalent Sigma the Sigma won - will be unloading mine !

[wintoid]

I always read things like this in the period between ordering the lens and it arriving :/

[Cadwell]

I always read things like this in the period between ordering the lens and it arriving :/

I wouldn't pay much attention if I were you. ;)

[wintoid]

I wouldn't pay much attention if I were you. ;)

Thanks! I needed that :D

Well as it's somewhere between Hong Kong and the UK right now, it's too late to go back anyway.

[evilenglishman]

I think this lens is much overrated it is not sharp frankly and on a shot for shot test with equivalent Sigma the Sigma won - will be unloading mine !

that statement is just rubbish - you must have a bad one!

[booggerg]

Now I think your 18-55 is bad. :lol: NO way the 18-55 can be that much worse than the 17-40

[KennyG]

Pretty classic 10D/20D misfocus evident on the second shot - try again. One reason why I won't touch either body with a bargepole...

Very broad statement. That shot is more indicitive of insufficient contrast to enable accurate focus, nothing more complicated than that. A 1 series body will have exactly the same problem, I know, trust me.

[paulo35]

Rubbish ?? I beg your pardon ! Useful comments would be welcome.

[evilenglishman]

I think this lens is much overrated it is not sharp frankly

I wouldn't call that comment particularly useful. :roll:
As I previously said, your comment is un-true unless, by a freak accident you have a bad copy.

I'm very sure the majority of people who have bought a 17-40 are extremely happy with it. Go on, ask them.

[phili1]

The 17 - 40 looks ok to me and tlike the other guy said there s n o way the 18 can be that b ad.

The problem with these test is you have to b e exact in what you do. If you want to test it then you have to be in a controlled enviroment. Your shot to me showed that the sun got brighter which could have give a bad reading, a blown out area will appear soft.

Set up three object, one at 5 feet center another back 2 to 3 feet to the left a little and a third 2 to 3 feet behind that and to the left of that, now center them in the viewfinder and focus on the center one. shoot 1 at F4 1 at F 5.6 1 at F 8, you should only see the DOF change. It should be all realativly sharp. That will give you a better comparison. Now all you have to do is pich an area where the Sun does not burn bright.

[tommykjensen]

The 17 - 40 looks ok to me and tlike the other guy said there s n o way the 18 can be that b ad.

Well my copy is and the other one I had when I still had my 300D was just as bad.


The problem with these test is you have to b e exact in what you do. If you want to test it then you have to be in a controlled enviroment. Your shot to me showed that the sun got brighter which could have give a bad reading, a blown out area will appear soft.


The sun did not get brighter while doing the last tests.

[phili1]

Well then you did all you can and you have a bad lens and 18-55. Some times people including me take shortcts whilt testing and get the wrong results.

Your original shot showed that it was sharp but the other objects should have been in focus as well ( to a degree) at F4.

Some times people do this test in Nine point focus ( you did not)and the camera keys in on a front object. If you have checked all your settings and you still find the same, then you have a problem.

I still think the 17-40 looks good the wall you cropped to is blown out and it is still sharp.

[Theo]

Tommy,

Didn't take me long (300 comparison shots) to find the DRebel Kit lens($100) was "Outperforming" the 17-40L ($800) with respect to exposure. Even with equal f-stop, aperature and shutter settings, the 17-40 was capturing underexposed images (inside and out) on the magnitude of one to two stops! Got a replacement ASAP from B&H and Now I see its Capability everyone talks about, WOW!!! Sharp, Great Color and Wonderful Bokeh!!! Decided to keep the Good Copy!

Ted

[wintoid]

As I got involved in this thread, I thought I'd pop back to say that I received my 17-40L today and it seems even sharper than my 50mm 1.4 prime. I'm really delighted by the 3d-ness of the images it's producing. The lens does not seem overrated to me at all, or at least I can say with certainty that my copy is absolutely excellent.

[Cadwell]

As I got involved in this thread, I thought I'd pop back to say that I received my 17-40L today and it seems even sharper than my 50mm 1.4 prime. I'm really delighted by the 3d-ness of the images it's producing. The lens does not seem overrated to me at all, or at least I can say with certainty that my copy is absolutely excellent.

Congratulations :D (I told you not to worry :wink: )

[cdhender]

As this is my next lense, I am very happy to hear these comments. This lense sounds amazing.

[drake]

I have also just gotten my 17/40 F4L today. With my EOS20D, I realised that with the same subject to camera distance(50cm), if I focus at 17mm and then zoom to 40mm, the spot that is focussed on does not look in-focus(not sharp) in the viewfinder. The subject only gets focused if I press the shutter button to refocus again at 40mm.

However, the image focused and taken at 17mm appears to be acceptably sharp when reviewing in pc at 100%.

Also, the image focused at 40mm and then taken at 17mm(with focus locked down) does not appear as sharp as the 1st image.....


Is this normal?

[Trumper]

Thanks! I needed that :D

Well as it's somewhere between Hong Kong and the UK right now, it's too late to go back anyway.
If you don't mind me asking,where did you get it from,i've been scouring the online shops and e bay dealers.
Cheers

[ShadowFlyP]

I have also just gotten my 17/40 F4L today. With my EOS20D, I realised that with the same subject to camera distance(50cm), if I focus at 17mm and then zoom to 40mm, the spot that is focussed on does not look in-focus(not sharp) in the viewfinder. The subject only gets focused if I press the shutter button to refocus again at 40mm.

However, the image focused and taken at 17mm appears to be acceptably sharp when reviewing in pc at 100%.

Also, the image focused at 40mm and then taken at 17mm(with focus locked down) does not appear as sharp as the 1st image.....


Is this normal?

Yes this is quite normal depending on the lens design. Some lenses allow you to focus and then change zoom without effecting the focus, others do not. It all depends on how the glass is laid out and which glass elements move when you change zoom. To be on the safe side you should always refocus if you change zooms.