TS-E 24mm Poor Performance

[wearle]

To all,

I rented this lens before I purchased it new. The rental appears to be an excellent copy so I was hoping the one I purchased would be too; unfortunately, it was a disappointment compared to the rental.

I tested this lens using stars. Stars are the toughest test for a lens, but they really show the lens' aberrations quite easily. I would like your thoughts and opinions on this lens. For example, is it a poor copy? If so, what do you think is wrong with the lens (e.g. De-centered, field curvature, etc.)? I have sent this lens to Canon for repair. I felt it had a De-centering problem. Upon return, the De-centering problem seems fixed, but now it seems to have a very bad field curvature problem. I'm no optics expert so perhaps something else may be wrong with lens. I plan on sending the lens back again with more data showing the problem I'm experiencing. I have included several links showing the rental lens and how it compares to my lens at each stage. The images are approximately 1.5 MB each.

I focused using LiveView with a 10X loupe using the belt stars of Orion near the center of the frame. The stars are trailing slightly due to using a fixed tripod.

As mentioned before, I just can't imagine how a $2200 lens can perform so poorly, especially since it is designed to cover 67mm. My TS-E 17mm is substantially better wide-open (see the last link). It is possible I have too high of expectations for the TS-E 24mm or just have a very bad copy. :-[

Rental non-shifted
http://www.northwest-landscapes.com/images/testing/ts-e_24mm_non-shifted_rental.jpg

Rental shifted 10 degrees
http://www.northwest-landscapes.com/images/testing/ts-e_24mm_shifted_10_degrees_rental.jpg

Purchased non-shifted
http://www.northwest-landscapes.com/images/testing/ts-e_24mm_non-shifted_purchased.jpg

Purchased shifted 10 degrees
http://www.northwest-landscapes.com/images/testing/ts-e_24mm_shifted_10_degrees_purchased.jpg

Purchased non-shifted "fixed"
http://www.northwest-landscapes.com/images/testing/ts-e_24mm_non-shifted_purchased_fixed.jpg

Purchased shifted 10 degrees "fixed"
http://www.northwest-landscapes.com/images/testing/ts-e_24mm_shifted_10_degrees_purchased_fixed.jpg

Purchased TS-E 17mm for comparison
http://www.northwest-landscapes.com/images/testing/ts-e_17mm_non-shifted.jpg

Thanks,

Wade

 

[NancyP]

Do what Roger Cicala suggests - send the repair center your test images, with methods and with commentary on your specific issue.

 

[surapon]

To all,

I rented this lens before I purchased it new. The rental appears to be an excellent copy so I was hoping the one I purchased would be too; unfortunately, it was a disappointment compared to the rental.

I tested this lens using stars. Stars are the toughest test for a lens, but they really show the lens' aberrations quite easily. I would like your thoughts and opinions on this lens. For example, is it a poor copy? If so, what do you think is wrong with the lens (e.g. De-centered, field curvature, etc.)? I have sent this lens to Canon for repair. I felt it had a De-centering problem. Upon return, the De-centering problem seems fixed, but now it seems to have a very bad field curvature problem. I'm no optics expert so perhaps something else may be wrong with lens. I plan on sending the lens back again with more data showing the problem I'm experiencing. I have included several links showing the rental lens and how it compares to my lens at each stage. The images are approximately 1.5 MB each.

I focused using LiveView with a 10X loupe using the belt stars of Orion near the center of the frame. The stars are trailing slightly due to using a fixed tripod.

As mentioned before, I just can't imagine how a $2200 lens can perform so poorly, especially since it is designed to cover 67mm. My TS-E 17mm is substantially better wide-open (see the last link). It is possible I have too high of expectations for the TS-E 24mm or just have a very bad copy. :-[

Rental non-shifted
http://www.northwest-landscapes.com/images/testing/ts-e_24mm_non-shifted_rental.jpg

Rental shifted 10 degrees
http://www.northwest-landscapes.com/images/testing/ts-e_24mm_shifted_10_degrees_rental.jpg

Purchased non-shifted
http://www.northwest-landscapes.com/images/testing/ts-e_24mm_non-shifted_purchased.jpg

Purchased shifted 10 degrees
http://www.northwest-landscapes.com/images/testing/ts-e_24mm_shifted_10_degrees_purchased.jpg

Purchased non-shifted "fixed"
http://www.northwest-landscapes.com/images/testing/ts-e_24mm_non-shifted_purchased_fixed.jpg

Purchased shifted 10 degrees "fixed"
http://www.northwest-landscapes.com/images/testing/ts-e_24mm_shifted_10_degrees_purchased_fixed.jpg

Purchased TS-E 17mm for comparison
http://www.northwest-landscapes.com/images/testing/ts-e_17mm_non-shifted.jpg

Thanks,

Wade

Dear wearle
Canon TS-E 24 mm F/ 3.5 L MK II are one of the sharpest lens in this world, But One of the most Difficult and Slowest Learning Curve too + Only Manual Focus, and Manual exposure adjustment for both Tilt and Shift Position. No Photographers that I know, who can master this Lens in 1 or 2 days------I have this Awesome Babe for 6-7 Months, and still just the beginner- user of this great Lens.
Yes, The Same thing happens to the Best Sniper Rifle in this world " the “Big Mac”, The McMillan Bros Tac-50 ", The Best Snipers must use, Train and Learn more than 6 Months in the Field with the helper , before go to the real action.
In my IDEA, Just my Idea, 99% of this Lens are great quality, May be 1% , the product on Friday Afternoon in MFG. and the workers want to go home early, and forget to check the quality control button----Ha, Ha, Ha.
Good luck for TS-E 24 L MK II
Surapon

PS, Two last Photos by my dear TS-E 24 L MK II, she with me 90% of my photography time.

 

[privatebydesign]

Do what Roger Cicala suggests - send the repair center your test images, with methods and with commentary on your specific issue.

They ignore them. Well that is my experience, I used to send prints and CD's with test images on along with the lens for repair, you get them back unopened.

The lenses are put on test equipment and are either up to factory specs or not; if they are then you get it back, if they are not then they work to make it so.

De-centering is a correctable alignment issue, I wouldn't think field curvature is as it is an inherent characteristic of any design.

Many lenses produce horrible comma in star images, but are superb photography lenses none the less. A star field test is not a good test for lens, unless your main subject will be star fields. Comma is but one aberration, and is often accepted in mitigation for reducing others.

Personally I think they are all within a hairs breadth of each other, comma will show much worse with a darker sky so your rental comparison is not a fair one. Similarly, the stars are much smaller with the 17 so produce less comma too. If you are not happy with the lens send it back, but if it is in specs they will just return it again. I'd do better IQ tests on more common subjects. If the lenses primary use is star fields I'd look at getting a lens more suited to the task, but wides and ultrawides are always going to be a problem.

A vastly cheaper alternative is to use the 1.4TC MkIII on the 17. One stop of light less, but excellent IQ and using the center of the lenses image circle.

 

[wearle]

To all,

Thanks, I appreciate all your comments.

I don't have a problem with the coma, it seems well corrected. The problem I have is the softness (i.e. lack of sharp focus) outside the "sweet spot". This lens' sweet spot seems to only be about a 20mm circle at best. I would figure a lens that covers 67mm should do significantly better. If you look closely at the ts-e_24mm_non-shifted_purchased_fixed.jpg image (i.e. the fourth link from the top), you will find almost the whole image is soft, except in a very small area near the center. I focused at infinity so the image should be quite sharp from 16 feet to infinity using a 24mm lens. The picture quality in the foreground (i.e. the hill side) is horrible. It just seems very strange this lens is so soft. I'll take more examples over the weekend, including star pictures to send to the Canon repair center in the Northeast. Hopefully, they will look at them.

Thanks,

Wade

 

[privatebydesign]

You can't compare different nights observations against each other, atmospheric conditions will make way more difference to your apparent sharpness than anything else. Honestly, star field observations are extremely limited in value in assessing lens performance, particularly if done on different nights at different times.

 

[Goldingd]

Looking at just two images, non-shifted_rental, and non-shifted_purchased I notice that the rental is a lot darker image. Looking at the Metadata both are at f/4 but ISO 3200 and ISO 1600 respectively, and 20 seconds vs 10 seconds. Also looking at the histogram, the rental is shifted way to the black and a bit clipped (as can be expected in a night sky) but the rental has a very centralized histogram with no contact to the black or white limits.

I do not think this is a fare comparison. The comparison needs to be of the same image on the same night using the same metering settings. This would be true if you were comparing the lens using a daytime exposure of say Half Dome, even more so for a long exposure at night looking at small twinkling highlights.

I do not suppose the rental is still at hand and perhaps a bit steep to just re-rent for a new test?

 

[JustMeOregon]

A star field test is not a good test for lens, unless your main subject will be star fields.

atmospheric conditions will make way more difference to your apparent sharpness than anything else

+1 I do believe that privatebydesign has nailed it...