70-200L IS IQ

[jl_moped]

Last night I did a few test shots with my 17-85 IS and 70-200L IS with identical settings: handheld, indoor with flash, Av f/5.6, uv filters. To my surprise, 17-85 IQ was better. This morning I did a few more shots in better settings. These shots were outdoor with natural light, on a tripod, same sensor to object distance, IS on, one shot AF on the lady's right eye, remote shutter release, pattern metering, Av mode, no flash, uv filters.

Photo 1: 17-85mm @70mm f/5.6 1/200s center crop ~10%
Photo 2: 70-200mm @ 70mm f/5.6 1/200s center crop ~10%

To my eyes, photos IQ look pretty close, should I be getting better IQ from the 70-200L IS? Also 70-200 at f/2.8 IQ was quite a bit lower. Should the IQ be relatively close throughout the entire range? Comment please.

[Tareq]

even the quality both are the same, each lens is for different use, so don't look on IQ only, just think of what the lens will be used for.

[basroil]

you either have an extraordinarily sharp 17-85, or those are not taken from a raw. from my experience, 70-200@f5.6 should cream the 17-85@f5.6... the 70-200 should also have a bit more kick in contrast, neither of which i'm seeing in these two images. try hosting them on imageshack and posting 10/12 quality dpp/photoshop 100% crop from a raw test. most of the details the 70-200 is capturing above the 17-85 are being destroyed by artifacting in the high jpg compression...

[Tareq]

I don't know why but i feel that you posted same photo twice, i can see even the lights are distributed and defused on both exactly the same, i can't get exactly the same angel of view with same composition with same light exactly while i am taken photos with different lens, should be little different even a size of a pin, focus on both pictures and you can see what i mean.

[Tareq]

Unless you didn't say that you used a tripod then i will say that you are a liar
Sorry for that, but what are you going to tell us? 17-85 IS better than 70-200 IS? and so what? both are Amazing and still 70-200 IS is more preferable i think.

[Ronald S. Jr.]

that's either user error or a damn poor copy of the 70-200. Of course, using a UV filter doesn't help, but still, that looks awful for the L.

[dontblink]

I would expect the IQ to be pretty close. Close enough to make it pretty much impossible to tell them apart on web images. The difference in a good lens or even a mediocre lens and a great lens are not shown in "friendly" photographic settings. What you are buying when you buy a 70-200L are things like f/2.8 constant aperature, lower chromatic aberrations, less distortion, less light fall off and better corner performance, more rugged build, weather proofing, etc.

The 17-85 is a good lens, unless you want your buildings to be strait at 17mm or you want to shoot without a flash in lower light conditions, etc.

[picturecrazy]

They ARE the same picture. here is the EXIF from the two files:

Camera Make: Canon
Camera Model: Canon EOS DIGITAL REBEL XT
Image Date: 2006:07:28 09:12:11
Flash Used: No
Focal Length: 70.0mm
CCD Width: 4.63mm
Exposure Time: 0.0050 s (1/200)
Aperture: f/5.6
ISO equiv: 100
White Balance: Auto
Metering Mode: Matrix
Exposure: aperture priority (semi-auto)


Camera Make: Canon
Camera Model: Canon EOS DIGITAL REBEL XT
Image Date: 2006:07:28 09:12:11
Flash Used: No
Focal Length: 70.0mm
CCD Width: 4.63mm
Exposure Time: 0.0050 s (1/200)
Aperture: f/5.6
ISO equiv: 100
White Balance: Auto
Metering Mode: Matrix
Exposure: aperture priority (semi-auto)


Unless you can take a shot, switch lenses and take another shot all within a second, they look to be the same image. You sure you didn't grab the wrong file when analyzing them?

[Ronald S. Jr.]

LOL...no wonder.

[Rhinotherunt]

Looks like the lens was not far enough from the subject to get the subject in focus. Mind the minimum focusing distance...

[chancellor]

LOL...no wonder.

Ron, there is another possibility that picturecrazy analyzed the same file twice :D

[ChopstickHero]

They ARE the same picture. here is the EXIF from the two files:

Camera Make: Canon
Camera Model: Canon EOS DIGITAL REBEL XT
Image Date: 2006:07:28 09:12:11
Flash Used: No
Focal Length: 70.0mm
CCD Width: 4.63mm
Exposure Time: 0.0050 s (1/200)
Aperture: f/5.6
ISO equiv: 100
White Balance: Auto
Metering Mode: Matrix
Exposure: aperture priority (semi-auto)


Camera Make: Canon
Camera Model: Canon EOS DIGITAL REBEL XT
Image Date: 2006:07:28 09:12:11
Flash Used: No
Focal Length: 70.0mm
CCD Width: 4.63mm
Exposure Time: 0.0050 s (1/200)
Aperture: f/5.6
ISO equiv: 100
White Balance: Auto
Metering Mode: Matrix
Exposure: aperture priority (semi-auto)


Unless you can take a shot, switch lenses and take another shot all within a second, they look to be the same image. You sure you didn't grab the wrong file when analyzing them?

are we being tricked here? lol

[picturecrazy]

Ron, there is another possibility that picturecrazy analyzed the same file twice :D

haha, actually, that's exactly what I thought I did.
I had to check 5 times before I convinced myself it was the same photo.

[Ronald S. Jr.]

Ron, there is another possibility that picturecrazy analyzed the same file twice :D

Very true. They're also not the same crop.

[Mr. Clean]

LOL - Great post! I needed a good chuckle today! hehe

[jl_moped]

I am sorry that the 2 photos are the same, I certainly was not trying to fool anyone. I have re-crop the 2 photos from the originals. Object was about 10 feet away from camera. Please check the exif to keep me honest.

Photo 1 is 17-85 crop to center, Promaster uv mc filter
Photo 2 is 70-200 crop to center, B+W uv mc filter

[Rhinotherunt]

Hmmm... 10 feet should be far enough. (I am guessing. I have a Sigma 70-200mm) Well, it looks like you have back focusing issues then.