Comparing 24-70L and 28-80 4.5-5.6 series V

[dampfish]

Here's the sketch: I've had been using the 28-80 for a while, but

had become increasingly disillusioned with my pictures. They just

seem to lack 'pop'. Finally after reading some related posts here

and there, I dug out some old slides taken with a 50 1.8 FD and

compared them. Ah ha! There *is* a difference!

 

So finally I could justify to the 'finance committee' a couple of

new lenses. My first purchase was a 24-70L. I have taken

comparison pictures with the old 28-90 and the new lens, and here's

the thing, I can't see any (or very very little) difference!

 

A series of pictures were taken across a range of apertures and

focal lengths. These were then projected to a size of about 5ft

along the longest edge. Film is Fuji Sensia 100. Shutter speeds

were in the range of 1/250 to 1/2.

 

So a couple of things occur to me:

1. I happen to have a spot on 28-80 (well... no... you're right)

2. I have a bum 24-70

3. The projector set up is crap

4. Maybe the problem is with the tripod

 

In consideration of 1 and 3, the old FD slides are fine (although I

have no direct comparision pictures). With respect to 4, top speed

was 1/250 and if memory serves, the old FD based pictures were

largely hand-held.

 

Any thoughts? Any suggestions on how I might get the 24-70 checked

out? FWIW - It was purchased from a well known NY store beginning

with B (and no, I have no issue with them) it's a US model, but I'm

in the UK. At the moment I'm hanging off buying a 28-70 2.8 IS

 

Thanks!

[nick_doan]

Bob,

 

what were your focal length and apertures? If you are taking pictures at 28mm at F4.5 on both lenses, you might want to consider shooting a subject about 25-50 feet away. When you project them, use a large piece of white paper (to make sure not to have any texture to the screen). Look for strong horizontal, vertical and diagonal lines; then see if the 24-70/2.8L is any sharper.

 

I have a hard time believing that it isn't. But that just might be a prejudice of mine. I'd say do the same test at F2.8, but obviously the 28-80 can't go there. ;)

 

If you are suspecting the projector, try getting them scanned in at the same best resolution, then looking at 100% crop of each.

 

If you suspect the tripod, just handhold some shots, and see how it goes.

 

 

Let us know how things turn out too!

[tawen_mei]

A lot of people on another Canon D-SLR forum are talking about how poor 24-70/2.8L is optically. I went through a couple of 24-70L and was very disappointed.

 

First, about my test setup: 10D w/ 550EX and a page of sheet music taped on the wall ten feet away. No ambient light, so camera shake wouldn't be an issue. Three shots per setting using far left, center, and far right focusing point on the target and 10D set to focus priority. Each shot focused individually, so even if the focal-plane isn't planar, that wouldn't be an issue.

 

At f/2.8, the image was fuzzy, and absolutely unacceptable at the edge. At f/4.0, slightly improved, but nowhere as sharp as my 28-135IS wide open. At f/8.0, finally it tied with 28-135IS at center with a bit more contrast, which is probably because my 28-135IS has collected quite a bit of dust after five years of abuse.

 

Contrary to lots of claims from "the other forum", there is no front/rear focusing problem with my 10D. The focusing point in the viewfinder maybe off but the AF system is very accurate. Another observation, the 50/1.4 was even worse than 24-70L until closed down to f/2.8 where it out resolved 28-135IS which out resolved the 24-70L.

 

The 10D has 1.6x magnification factor, so my "edge" is really half-way toward the edge on film camera of the 1Ds. Even then, the 24-70L was horrible! I am becoming wary of claims that the "L" and prime lenses blow the cheap consumer stuff away. My old Tamron 24-70/3.5-5.6 did better when I used to scan negatives, and my first lens, the 35-80/4.5-5.6 that came with Rebel G, probably did just as well as 24-70L.

 

I am returning the 24-70L for the second time... I bought it because I wanted something a bit wider to cope with the 1.6x FOV, and perhaps something sharper at the same time, but the 24-70L is just horrible unless you close it down to f/11.

 

Has anyone performed similar test on 24-85?

[gareth_harper]

All I can add is that I bought the EOS30 kit as my entry into autofocus cameras, it came with a 28-90 f4-5.6 and a 75-300 f4-5.6.

I quickly became fustrated with the 28-90 in particular in the darkroom. The 10x8 prints I have done with the 28-90 look soft and the resolution or detail is poor, they simply don't look 'right'.

I then got a 28-80 f2.8 Tokina and now I'm turning out nice sharp detailed prints all the time. Primes are better still and I use em when I can but that Tokina is not that far behind.

I'm still using the 75-300 as it's quite good really though I know there is better out there and I intend to upgrade one day, but the 75-300 is no where near as bad as the 28-90 which is really at the end of the day quite a poor lens.

[duane_kucheran]

Modern zooms are very good and very versatile, and have resolution similar to primes but their complexity does limit them in other ways.

One thing to consider is that the 50 f/1.8 is a far simpler lens and can probably do a better job than the zooms will at 50 mm. It will have less flare and greater contrast because it only has 8 glass to air surfaces vs. the 26 in the 24 - 70. Also, by the time the 50 mm is stopped down to f/2.8 - f/4 it's pretty close to it's optimum whereas the zoom is running flat out.

 

When I look back at the images I've made, the snappiest ones were made with the simplest, slowest lenses. They weren't always the sharpest but they had the greatest contrast and the most pure colors.

 

FWIW anyway,

 

Cheers,

[kristian dowling]

I think tawen is misguided and is trying to justify the fact he can't afford the more expensive L glass. Seeing that the EOS 10D image sensor only uses part of the image provided by the glass, there could not be such a poor performance as he stated, especially considering he says he tried a few samples.

 

Plus, the dead give-away is the fact that he didn't mention anything about focal lengths, which of course would vary slightly at different apertures- as would any zoom lens. As far as I have heard from genuine and creditable sources, the l glass- especially the 24-70 is fantastic- as is my 16-35L!!!

[yakim_peled1]

Well, I never used any but here (http://luminous-landscape.com/reviews/lenses/24-70-review.shtml) is a pro photographer which seems to be quite happy from wide open shots of the 24-70/2.8.

[tawen_mei]

Here are just two test results among many others. For those who are thinking about buying, or just did and it's not too late for full-refund, I urge you to do your own testing and post the results for the benefit of others. For those who already made the purchase, it's probably better to be ignorant and just be happy with it.

 

The test condition is 10D w/ 550EX as main light source. Lens re-focused using the nearest focusing point before each shot. Results cropped and contrast adjusted to account for lighting variations.

 

If the links don't work, just go to my portfolio...

 

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<img src="/photodb/image-display?photo_id=1435982&size=lg" height=387 width=1129 hspace=10>

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<img src="/photodb/image-display?photo_id=1435988&size=lg" height=419 width=1158 hspace=10>

[kristian dowling]

wow, those are some shots....any explanation???