If you own a 16-35mm f/2.8L, I'd like your help!

04/13/2005 08:34:39 PM · #1

Hi fellow 16-35 owner...could I enlist your help?

I just got my lens and am testing it and would like your opinion...it seems kind of softish and I'm wondering if it's back-focusing. I need your help to determine what you think of my test shots and whether I'm expecting too much at f/2.8...

Also, your suggestions on how best to test it...

Here's a sample "100% crop" of the focal point at 35mm f/2.8:

More questions/tests to follow, I'd just like to start slow...

Message edited by author 2005-04-13 20:35:04.

04/14/2005 07:49:49 AM · #2

bump

Falc

Canon EOS-1D Mark III

04/14/2005 08:12:20 AM · #3

Hi Mike,

I have the 16-35 f2.8 'L', and I'm very very impressed with the sharpness. Superior to even the primes I used before.

The focus on your image does feel a tad soft I must admit. I'll post a crop from one of my images this evening when I get home. If you go to my pbase gallery (link below) you will see an image of the London Eye taken yesterday with the 16-35, its not a 100% crop obviously, but will show you what I get with mine.

Falc

Canon EF 24-105mm f/4.0L IS

04/14/2005 08:18:54 AM · #4

Thanks Falc...at f11, I'm loving what I get out of it. Otherwise, the contrast is beautiful and the speed of the USM is incredible!

I look forward to some of your samples...especially at f/2.8...thanks!

I'm going to try the 'brick wall test' if I get a chance this evening.

mariomel

Canon EOS-5D

04/14/2005 08:53:38 AM · #5

Originally posted by thatcloudthere:

I'm going to try the 'brick wall test' if I get a chance this evening.

I'm not sure that this test will help you determine if you have a back/front focus issue. When I tested my lenses, I used a page from a book and shot at about a 35Âº angle. I set the camera on a tripod, and shot using the timer and mirror lock-up, to avoid any user errors. I focused on a specific word and saw what was in focus on the shot. I was able to determine that my lens (70-200 f/4 L) haad a back focus issue. I sent it in to Canon and I now see why everybody was raving about this lens. It was definitely worth the effort and time.

That being said, given the shot you took, it looks like it's a tad soft, but I would definitely do some more controlled testing before jumping to the conclusion that the lens is off. That lens is supposed to be awesome.

Good luck. I hope this helped.

04/14/2005 09:06:29 AM · #6

Originally posted by mariomel:

Originally posted by thatcloudthere:

I'm going to try the 'brick wall test' if I get a chance this evening.

I'm not sure that this test will help you determine if you have a back/front focus issue. When I tested my lenses, I used a page from a book and shot at about a 35Âº angle. I set the camera on a tripod, and shot using the timer and mirror lock-up, to avoid any user errors. I focused on a specific word and saw what was in focus on the shot. I was able to determine that my lens (70-200 f/4 L) haad a back focus issue. I sent it in to Canon and I now see why everybody was raving about this lens. It was definitely worth the effort and time.

That being said, given the shot you took, it looks like it's a tad soft, but I would definitely do some more controlled testing before jumping to the conclusion that the lens is off. That lens is supposed to be awesome.

Good luck. I hope this helped.

Yeah, the brick wall test is just to test edge to edge sharpness. I forgot about using a book to test...great idea, I'll do that tonight.

Also, do you think it might be my 300d? I've heard from others that had backfocusing issues and were disappointed with their 16-35 on the 10d but when they got the 20d it was tack sharp. Hmmm....

After applying USM, though (especially at smaller than wide-open apertures)...this lens is perfect! I love this thing.

LEONJR

Fujifilm FinePix S3 Pro

04/14/2005 09:32:14 AM · #7

How do back and front focusing issues start or should i say how are they caused? thanks

Leon

PaulMdx

Canon EF 70-200mm f/2.8L USM

04/14/2005 10:59:54 AM · #8

Originally posted by thatcloudthere:

Also, do you think it might be my 300d? I've heard from others that had backfocusing issues and were disappointed with their 16-35 on the 10d but when they got the 20d it was tack sharp. Hmmm....

The 10D is known to have a back-focus issue. To my knowledge the 300D doesn't.

bod

04/14/2005 11:06:33 AM · #9

Sorta thinking out loud here, but ...
The side of the tree is obviously more in-focus than the front. The side of the tree is also more contrasty. Remembering that the actual area used by the auto-focus system is larger than the squares you see in the viewfinder, is it possible that the camera did in fact focus on the edge of the tree?

The usual: what shutter speed? and: did you use a tripod? questions also apply.

04/14/2005 11:14:11 AM · #10

Originally posted by bod:

At f/2.8 the shutter speed was around 1/2000 or something like that...all of my shots were taken with a tripod.

The focus point was the centre point and the crop is taken from the centre of the pic. I agree, the side of the tree looks more in-focus which is why I'm concerned that perhaps my lens is back-focusing.

The strange thing is, I was playing a bit more and when I focus on something then manually adjust the focus it seems that the AF did catch it correctly...hmm....more tests to follow (perhaps on my lunch break).

Message edited by author 2005-04-14 11:15:44.

PaulMdx

Canon EF 70-200mm f/2.8L USM

04/14/2005 11:16:08 AM · #11

Mike,

Do you have a crop from the ground near the tree? Does that give any indication of the focus plane?

Message edited by author 2005-04-14 11:16:20.

04/14/2005 11:20:38 AM · #12

Originally posted by PaulMdx:

Mike,

Do you have a crop from the ground near the tree? Does that give any indication of the focus plane?

Not with me here at work...from what I remember it was a whole lot sticks and brush so it would be difficult to tell, but I'll check that out as well.

I tried the tape measure test and it seemed fairly decent...it's really hard to test such a wide lens because it captures so much at once and when you blow up to 100% I'm not left with as much detail as when I blow up my 50mm shots. I know this is obvious, but it's surprising to see a 100% crop that looks like the field of view on a shot taken at 50mm!

PaulMdx

Canon EF 70-200mm f/2.8L USM

04/14/2005 11:22:58 AM · #13

Originally posted by thatcloudthere:

I tried the tape measure test and it seemed fairly decent...

I had an issue with an EF-S 10-22mm being soft a week or two ago. At close distances it appeared pretty good - it was only at longer distances it became a lot softer.

Canon EF 24-70mm f/2.8L USM

04/14/2005 11:29:09 AM · #14

Originally posted by PaulMdx:

Originally posted by thatcloudthere:
I tried the tape measure test and it seemed fairly decent...

I had an issue with an EF-S 10-22mm being soft a week or two ago. At close distances it appeared pretty good - it was only at longer distances it became a lot softer.

Did you have trouble testing it? It just seems that if I focus on a stop sign that is 10m away I can barely tell if it's in-focus when I get it on my PC. Because once I blow it up (even at 100% crop) I don't have much detail on the stop sign to judge whether it's sharp or not!

Message edited by author 2005-04-14 11:30:41.

doctornick

Apple iPhone 13 Pro

04/14/2005 12:28:25 PM · #15

Originally posted by thatcloudthere:

LOL it looks pretty good to me, did you shoot in JPG mode? What are the sharpening parameters? That photo looks like a teeny bit of USM will get it to where it should be.

Canon EF 24-70mm f/2.8L USM

04/14/2005 12:44:06 PM · #16

doctornick!!

I was hoping you'd show up! I was about to email you but I figured I'd just wait til you saw the thread.

The paramaters were AdobeRGB shot in .jpg...I know, I know, I should know by now..."Shoot RAW!"

And you're right, USM takes care of it...I think that I'm in danger of becoming a pixel-peeper.

Thanks for taking a look!

Overall, I am loving this lens!

Message edited by author 2005-04-14 12:45:20.

doctornick

Apple iPhone 13 Pro

04/14/2005 12:47:35 PM · #17

No worries! That lens lived on my 300D, great walk around lens for a 1.6x crop camera.

04/14/2005 12:52:49 PM · #18

Originally posted by doctornick:

No worries! That lens lived on my 300D, great walk around lens for a 1.6x crop camera.

I love full-time manual focus...internal zoom/focus...USM - At first I didn't think the AF was even working, it was so fast and quiet!

Once I apply USM and boost the saturation and contrast in PS, the photos just POP!

Lovin' it.

04/14/2005 05:46:20 PM · #19

I'm very happy to report that I think it was all in my head...

This is a 100% crop of the 'book test' I did at 35mm at f/2.8. I focused on the word "for" in the sentence "and for the systems"...

Straight out of camera, no USM applied:

So I'm happy!

Message edited by author 2005-04-14 17:46:54.