I tested at infinity for all four corners at all full-stop apertures from f/2.8 to f/11, at 14mm, 18mm, 21mm, and 24mm. I also tossed in some quick flare and distortion tests.
p.8 #2 · Sigma 14-24mm f/2.8 DG DN first impressions
A bit hard to say for sure, as it's not obvious to me where focus was on each shot, but possibly wide open your copy looks a little more asymmetrical than mine at the wide end, but a little better at the long end.
Looks like we have only one copy among half a dozen or so reported on thus far that is really well centered across the whole range.
Stopping down to 5.6 or so seems to improve things substantially with yours, as is also the case with mine.
Flare tests look pretty good to me for a lens with a bulbous front element imo. Distortion definitely wants a profile at the wide end when you have straight lines near the edges.
p.8 #3 · Sigma 14-24mm f/2.8 DG DN first impressions
rvh23 wrote:
A bit hard to say for sure, as it's not obvious to me where focus was on each shot, but possibly wide open your copy looks a little more asymmetrical than mine at the wide end, but a little better at the long end.
Looks like we have only one copy among half a dozen or so reported on thus far that is really well centered across the whole range.
Stopping down to 5.6 or so seems to improve things substantially with yours, as is also the case with mine.
Flare tests look pretty good to me for a lens with a bulbous front element imo. Distortion definitely wants a profile at the wide end when you have straight lines near the edges....Show more →
Thanks for the analysis. My focus was not on a specific spot. I generally focused in the middle, although I think I missed my focus on the 14mm shots (I think I hit the front pole). I agree that the lens really improves around f/5.6 in the corners. At f/11, diffraction is very noticeable. 24mm is the weakest FL on my copy. 14 and 18 are really sharp. 21 is decent.
This weekend, I intend to spend more time testing. I want to test center focus vs. corner focus to get a better sense of the field curvature. I also need to do a star test and see how the coma fares. I hope mine performs as well as yours. I also want to do more discrete testing from f/5.6 to f/8 to find the sweet spot. Hopefully I will get better conditions, as it was windy today. I also shot hand-held. I will use a tripod next time now that I know my copy is fairly symmetrical. I need to find a better wall to test against. I also plan comparison tests, as I can test it against overlapping FLs with the VC15, Loxia 21, 24GM, Canon 16-35/4, Canon 24-70/2.8 II, and Sony 24-105. I could test the Canon 24-105/4, but I already know this lens will trounce it.
I thought the lens did fairly well in the flare tests. The front end is bulbous, but not as exposed as the Canon TS-E 17mm, which is nice.
p.8 #4 · Sigma 14-24mm f/2.8 DG DN first impressions
I'll look forward to your comparison against the Loxia 21 in particular. In my comparison at F2.8 against the CV 21/1.4 my zoom's best corner @21mm looks at least as good as the CV, but its poorest corner unfortunately doesn't.
Stopped down to my typical landscape shooting apertures of F6.3 to F8, the Sigma zoom and CV21 are very similar. Much more so than my GM 16-35 or Sony 12-24 were in comparison to my Loxia 21 when I compared those some time ago.
p.8 #5 · Sigma 14-24mm f/2.8 DG DN first impressions
Below is an assessment of astro performance with the 14-24 at 24mm F2.8, where my copy of the lens shows the greatest asymmetry in my 'terrestrial' centering tests. I set focus to "12m" which is pretty much infinity at 24mm on this lens, looked for the brightest sky object I could see, and placed it in turn in the center of the frame, and the four corners, without changing focus, taking a 5 sec shot each time.
Shown are 100% crops of that sky object and a few surrounding stars (from 42mp, with minimal sharpening), from those five shots.
The lens asymmetry doesn't seem to have a large effect on relative performance of the corners. I have seen this before, and have wondered if it's because many of the stars might actually span less than one pixel in the FOV, so that a slightly blurred star and a sharp star might not look very different at the pixel level. Please let me know if there is another explanation.
p.8 #6 · Sigma 14-24mm f/2.8 DG DN first impressions
Thanks for you files.
This is a very interesting job.
First sight seem to me that here there is nothing special compared to Sony 12-24 on similar test.
Very good lens considering it is a Zoom lens and I think very good copy.
If/when you have time would you please be so kind to post these 6 RAW files?
14mm, 18mm and 24mm at 2.8 and 8.0?
The images should be horizontal at almost infinity and, most important, RAW.
p.8 #7 · Sigma 14-24mm f/2.8 DG DN first impressions
scalanc2 wrote:
Thanks for you files.
This is a very interesting job.
First sight seem to me that here there is nothing special compared to Sony 12-24 on similar test.
Very good lens considering it is a Zoom lens and I think very good copy.
If/when you have time would you please be so kind to post these 6 RAW files?
14mm, 18mm and 24mm at 2.8 and 8.0?
The images should be horizontal at almost infinity and, most important, RAW.
p.8 #8 · Sigma 14-24mm f/2.8 DG DN first impressions
I got the 14-24 from UPS today and immediately tested it against my Sigma 14 f/1.8 and Sony 24mm f/1.4 on an A7 III. In short, the lens is phenomenal. Absolutely amazing.
Test notes:
- My usage case is astrophotography, so I am particularly interested in top corner performance.
- The lenses were focused in the center and not refocused for the corner crops. If a lens has field curvature, this will make it very obvious.
- Images were processed in ACR with default sharpening. The "remove CA" box was checked. In-camera aberration corrections were disabled.
- Clouds were passing in front of the sun, so differences in brightness are not significant.
This will save a solid 2 pounds of backpacking weight compared to carrying the Sigma 14 1.8 + Tokina 20 f/2.
p.8 #9 · Sigma 14-24mm f/2.8 DG DN first impressions
Excellent. Probably quite similar to mine if I look at the same corners. Only a bit of asymmetry wide open, more so at the long end, but even there near flawless by 5.6 (and sooner at the wide end). I agree it's a phenomenal zoom. A bit better than the 14/1.8 wrt to coma too.
p.8 #10 · Sigma 14-24mm f/2.8 DG DN first impressions
Besides mis-focus, or a sub-par copy, I can't understand why the Sony 24 GM is showing so much CA open apertures in the center? I know my copy didn't have it.
p.8 #11 · Sigma 14-24mm f/2.8 DG DN first impressions
pdmphoto wrote:
Besides mis-focus, or a sub-par copy, I can't understand why the Sony 24 GM is showing so much CA open apertures in the center? I know my copy didn't have it.
I know my copy has it with the right subject. U really have to have a very strong white subject against a very dark background to show it.
For my copy of the 24mm, it is very subject dependent when showing ca.
A lot of reviews has mentioned the ca so I doubt your copy is any different.
p.8 #12 · Sigma 14-24mm f/2.8 DG DN first impressions
Sean Goebel wrote:
I got the 14-24 from UPS today and immediately tested it against my Sigma 14 f/1.8 and Sony 24mm f/1.4 on an A7 III. In short, the lens is phenomenal. Absolutely amazing.
Test notes:
- My usage case is astrophotography, so I am particularly interested in top corner performance.
- The lenses were focused in the center and not refocused for the corner crops. If a lens has field curvature, this will make it very obvious.
- Images were processed in ACR with default sharpening. The "remove CA" box was checked. In-camera aberration corrections were disabled.
- Clouds were passing in front of the sun, so differences in brightness are not significant.
This will save a solid 2 pounds of backpacking weight compared to carrying the Sigma 14 1.8 + Tokina 20 f/2....Show more →
p.8 #13 · Sigma 14-24mm f/2.8 DG DN first impressions
scrappydog wrote:
Thanks for the analysis. My focus was not on a specific spot. I generally focused in the middle, although I think I missed my focus on the 14mm shots (I think I hit the front pole). I agree that the lens really improves around f/5.6 in the corners. At f/11, diffraction is very noticeable. 24mm is the weakest FL on my copy. 14 and 18 are really sharp. 21 is decent.
This weekend, I intend to spend more time testing. I want to test center focus vs. corner focus to get a better sense of the field curvature. I also need to do a star test and see how the coma fares. I hope mine performs as well as yours. I also want to do more discrete testing from f/5.6 to f/8 to find the sweet spot. Hopefully I will get better conditions, as it was windy today. I also shot hand-held. I will use a tripod next time now that I know my copy is fairly symmetrical. I need to find a better wall to test against. I also plan comparison tests, as I can test it against overlapping FLs with the VC15, Loxia 21, 24GM, Canon 16-35/4, Canon 24-70/2.8 II, and Sony 24-105. I could test the Canon 24-105/4, but I already know this lens will trounce it.
I thought the lens did fairly well in the flare tests. The front end is bulbous, but not as exposed as the Canon TS-E 17mm, which is nice.
Overall, I am really happy with the performance....Show more →
I just downloaded your samples and the flare looks horrible. It is much worse than I have ever seen on my 12-24mm.
The ghosting on my 12-24mm is always much smaller than that. That makes the decision for me, not to change the 12-24mm to this sigma.
p.8 #14 · Sigma 14-24mm f/2.8 DG DN first impressions
If you arrange just the right circumstances you can make any lens flare strongly, even Loxias. In general though, and having used both , I've found the Sigma zoom is much more flare resistant than the Sony 12-24. Flare is a known weakness of the Sony, and particularly its ring flare is often difficult to deal with.
p.8 #15 · Sigma 14-24mm f/2.8 DG DN first impressions
rvh23 wrote:
If you arrange just the right circumstances you can make any lens flare strongly, even Loxias. In general though, and having used both , I've found the Sigma zoom is much more flare resistant than the Sony 12-24. Flare is a known weakness of the Sony, and particularly its ring flare is often difficult to deal with.
Yup, I noticed the ring flare from the Sony very often. But it is a skinny ring.
I just took my Sony and shot about 30 shots against the sun various angles, some with sun peeking out of a building.
I always get the small ghosting plus a skinny ring for flare. Nothing like the Monster ghosting shown in those samples.
As a matter of preference I much prefer the ring flare than a huge ghost.
p.8 #18 · Sigma 14-24mm f/2.8 DG DN first impressions
wind30 wrote:
The previous post shows the flare from 12-24mm. It is the worst flare out of 30 pics into the sun.
I see this ghosting + ring quite often but never anything like the one below from the sigma 14-24mm
http://www.keehian.com/img/flare2.jpg
Ya, it's hard to say for sure if you don't have them tested side by side (both lenses aren't at the extremities of the spectrum). I remembered when the GM 24 was just released, a few said that lens had atrocious flare as well. But in the end, it depends on the situation. Both Sigma and Sony coatings are not at the top of the industry in term of flare reduction. I couldn't get mine to flare that much so far.
On each FL at f/2.8, I focused on the yellow industrial machine near the middle of the frame, or the curved highway sign just to the right of the machine. I couldn't get the corners at the same infinity distance because of the location, but this sample should be (hopefully) enough for your needs. I will seek a better location and let you know if I do.
p.8 #20 · Sigma 14-24mm f/2.8 DG DN first impressions
wind30 wrote:
The previous post shows the flare from 12-24mm. It is the worst flare out of 30 pics into the sun.
I see this ghosting + ring quite often but never anything like the one below from the sigma 14-24mm
http://www.keehian.com/img/flare2.jpg
I would wait to see other results before making a decision. I live in Colorado, which is high altitude (5960' / 1823m) and the sun is super bright and intense.
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