Help eval Canon 24-70

Bodley

Need help evaluating Canon 24-70L. This is a shot of a wall taken with 1dmkII straight out of camera - raw - without any sharpening applied.



Any help is appreciated.

Mongrel

Hi Bodley...
Initial impression-it looks good to me. Sharp, color is well rendered, no obvious distortion, etc.

It would help if we had more information-i.e.

What focal length?
What aperture?
Shutter speed?
AF or manual focus?

and so forth.

You might consider crops of the corners and center if you have concerns about sharpness.

Is there something in particular that you are looking for? For me, if it looks this good on a wall shot, I highly doubt you would have any problems with your 'real world' shots as they say.

Bodley

Mongrel wrote:

Initial impression-it looks good to me. Sharp, color is well rendered, no obvious distortion, etc.

It would help if we had more information-i.e.

What focal length?
What aperture?
Shutter speed?
AF or manual focus?

and so forth.

You might consider crops of the corners and center if you have concerns about sharpness.

Is there something in particular that you are looking for? For me, if it looks this good on a wall shot, I highly doubt you would have any problems with your 'real world' shots as they say.

The exif data is visible by clicking on the photo.

I've shot some real world photos and have mixed feelings. Just finished shooting 300 T&I's - off a ladder - and the results, while very good, didn't seem as crisp as expected. Could be camera shake, I was on a ladder.

How can camera shake, out of focus and bad lens be distinguished from each other from looking at a photo?

jimf

Bodley wrote:

How can camera shake, out of focus and bad lens be distinguished from each other from looking at a photo?

You could use a tripod to minimize camera shake. Bad lenses tend to have a variety of nastyisms: Chromatic abberation, distortion, and/or vignetting at the edges, for instance. Shooting a flat grey color field can help find chromatic abberation and vignetting, shooting something with straight vertical and horizontal lines (as you did) is great for picking out distortion. You didn't mention which body you're using but if it's one of the cameras with a cropping factor you're less likely to see problems on the edges. Your profile says you have a 1DmkII in which case that wouldn't be you :-).

In any case that is not a bad lens by any stretch of the imagination. Unless it's flawed in manufacture, which is rare for these lenses, it's hard to do better. I have the older model, the 28-70 f/2.8 L, and it's my workhorse lens. Very, very happy with it.

Bodley

jimf wrote:

You could use a tripod to minimize camera shake. Bad lenses tend to have a variety of nastyisms: Chromatic abberation, distortion, and/or vignetting at the edges, for instance. Shooting a flat grey color field can help find chromatic abberation and vignetting, shooting something with straight vertical and horizontal lines (as you did) is great for picking out distortion. You didn't mention which body you're using but if it's one of the cameras with a cropping factor you're less likely to see problems on the edges. Your profile says you have a 1DmkII in which case that wouldn't be you :-).

The wall was shot using a tripod and 1dmkII.

Khaos

I'm really not sure what you are looking for.

Generally, you would go wide open, thus 2.8 at 24 and 70, and possibly try the mid at 50. Then compare 100% crops of the middle and corners. Then move down, 4, 5.6, 8, etc.

The pic you have is small and personally I never like the brick wall for testing.

The bottom line for me and should be for everyone, is you know what looks sharp to you. If it isn't meeting your standards, sell it.

Seriously it's like TVs or audio. 10 people can look and listen to 10 differemt TVs and 10 different audio receivers and everyone will differ on what gives the sharpest picture and the clearest sound.

Bodley

Khaos wrote:

I'm really not sure what you are looking for.

First of all - anytime I buy a new lens I get paranoid that it's a bad copy (I'm sure it's some kind of neurosis).

I got this particular lens and shot some basketball T&I's. I just felt that the shots could have been sharper. But maybe not. My whole setup was new to me (Two off camera flashes in addition to the on-camera with bracket).

I thought I was braced but the sharpness may have suffered from camera shake since I was on a ladder for hours. But I was shooting 1/200 at focal lengths less than 70mm (91mm with 1.3 1dmkII factor) so I would not think shake would be a factor. Just not sure how to identify shake on a photo.

wxwax

T&I = test and integration?

I agree that it doesn't look very good. I got the original and looked at it in PS, not at all sharp.

Manual focus or auto focus?

Bodley

wxwax wrote:

T&I = test and integration?

I agree that it doesn't look very good. I got the original and looked at it in PS, not at all sharp.

Manual focus or auto focus?

T&I - Team and Individual.

Auto but checked manual.

Bodley

So if it's not a sharp copy will Canon fix it or just claim it's "within Spec."

wxwax

Bodley wrote:

So if it's not a sharp copy will Canon fix it or just claim it's "within Spec."

You have any other demo shots?

Bodley

wxwax wrote:

You have any other demo shots?

Have several hundred on my site but they have been manipulated, originals available, few more of the wall and some candids. What kind of shot are needed?

wxwax

Bodley wrote:

Have several hundred on my site but they have been manipulated, originals available, few more of the wall and some candids. What kind of shot are needed?

Anything that would show if the lens or the camera body has a problem.

Similar shots with two different lenses, that sort of thing. A real test of the lens and the body.

Bodley

wxwax wrote:

Anything that would show if the lens or the camera body has a problem.

Similar shots with two different lenses, that sort of thing. A real test of the lens and the body.

The action shots I took in the same gym with my 70-200mm/f2.8 seem much sharper.

Here are a few more shots with the 24-70 - no sharpening applied.

Andy

Hi Bod,

I looked at the origs and they look like most 24-70 shots I've seen. I'd say it's "within spec" - that lens is loved and hated equally, I think.

I wish I could give you a better answer, mate.

Happy New Year

Andy

Bodley

Did more test (w/ newspaper) with the 24-70 and also compared results to my 70-200.

Focus was not an issue however there was excessive perimeter distortion. I should have my replacement by Wed.

DanielB

its obviously flawed. i'll take it off your hands for free

AND, i'll even pay shipping

Bodley

DanielB wrote:

its obviously flawed. i'll take it off your hands for free

AND, i'll even pay shipping

Thanks, but No Thanks

wxwax

Bodley wrote:

Did more test (w/ newspaper) with the 24-70 and also compared results to my 70-200.

Focus was not an issue however there was excessive perimeter distortion. I should have my replacement by Wed.

Post some identical shots with the new glass. I'll be very interested to see if there are any differences.

Bodley

wxwax wrote:

Post some identical shots with the new glass. I'll be very interested to see if there are any differences.

What are you expecting?

Okay, I'll post photos of a newspaper.

Following your suggestion, I shot a newspapers with my 70-200/f2.8 IS and 24-70/f2.8 for comparison purposes. The 70-200/f2.8 IS beat the 24-70/f2.8 hands down thus the replacement request.