Discussion on Lens Performance: Sigma 180mm Macro f3.5

[Ian]

I would caution everyone looking to purchase a Sigma 180 to check that out first. I have no idea if the methodology was sound or not, but from that, I wouldn't touch the Sigmas with a barge pole. I've never owned a Sigma because I could never put up with their build, and to a lesser extent their focusing, but based on that test I wouldn't touch them because of their shocking image quality too.

Like I said, I cannot vouch for the accuracy of that test, but it's worth considering. Based on that, I'd sell the Sigma if anyone gave it to me.

I've just read the test and his methodology while not perfect was however acceptable as a test for basic lens resolution and focusing accuracy.

The one major area the reviewer didn't cover was bokeh, which due to the nature of the conceived test was impossible to test as he was essentially shooting a 2D flat object which is fine for measuring the focusing accuracy and resolution of a lens at various apertures in a side by side comparison.

A bokeh test as I know you're aware would require a 3D object with a background some distance beyond the target subject. This could have been arranged by using a plastic flower or a silk flower for example and controlled lighting.

However with the qualification about the bokeh testing I consider the rest of the test proceedure to be valid and to leave the determination of the value of the Sigma lens to those people who are contemplating purchasing one.

Ian

 

[Darren]

This discussion is split off from Keng Hor's MO thread so as not to detract from the MO.

Civil discussions on the relative performance (or lack thereof) can continue here = please note the word civil.

 

[kenghor]

Howcome my post is snipped off? OK, let me try to repeat in case people wonder what I had to take a pail of salt:

In Jed first posting, he simply slapped down Sigma without making any reference to the lens test article. He has also mentioned that he had never used any Sigma lens before. Basing on such groundless claim, I will not buy his comment and thinks that he's a trouble maker coming in to spoil my Mass Order.

If he had given the link to support his statement, which he had later, I will be glad for the extra info. Will take it with a grain of salt.

 

[Darren]

Howcome my post is snipped off? OK, let me try to repeat in case people wonder what I had to take a pail of salt:

Keng Hor,

Your original MO thread is still here - http://forums.clubsnap.org/showthread.php?t=56112 - complete with the people who ordered.

We just split off the discussion on lens performance so as not to detract from your original MO purpose.

 

[kenghor]

Just got the Sigma 180mm lens today and shot some pictures with the 300D.
The lens is really solid and handling is great. AF haunts but is acceptable for a macro lens standard. Went to CP to try out the Tamron lens just before I used the Sigma. The Tamron really feel plastic and AF is really slow as compared to the Sigma.

Image wise for the Sigma is ok too though I've not done any scientific testing yet.

f5.6. Very creamy and smooth bokeh.

f9. Pretty sharp.

 

[Ian]

Just got the Sigma 180mm lens today and shot some pictures with the 300D.
The lens is really solid and handling is great. AF haunts but is acceptable for a macro lens standard. Went to CP to try out the Tamron lens just before I used the Sigma. The Tamron really feel plastic and AF is really slow as compared to the Sigma.

Image wise for the Sigma is ok too though I've not done any scientific testing yet.

While I applaud your efforts the results are flawed and here's why:

1) a small image such as the ones you posted show us nothing about the real performance of a lens as the image scale isn't sufficient to show any real detail. See Jed's excellent post on this in the technical discussion forum.

2) Anyone who uses AF for macro work has rocks in their head as AF focusing simply isn't accurate enough for the precision focusing required for macro or 1:1 shooting.

Keep on trying

 

[kenghor]

certain qualities of the lens need not have to be blown up to evaluate.

while one can't judge sharpness, one can clearly see the creamy bokeh on the above pixs.

Another issue is the out of foucs highlight. While many has complained that the Canon 180mm L produces objectionable octogeon highlights, the highlights produces by the Sigma is very nice.

any idiots can tell these lens properties just looking at the above pix.

 

[kenghor]

AF for macro?

Yes, I want it shots of a relative flat object.

As the AF range is very wide, I want the AF to bring the subject to rough focus before I fine tune it. If u have never done it before, try searching for your subject with a 180mm macro lens. It could be thrown so out of focus that u can't see it. The AF will certainly helps here.

Of course u can do it with MF. But I had knock myself with rocks when the AF failed on my Canon 100mm macro. How I wished I had the AF working.

 

[Zerstorer]

Hi, could you post some samples of the following?

1)Shots with a messy background
2)100% crops of high-contrast/backlit subjects
3)100% crop of a 1:1 reproduction to show the detail/sharpness.

 

[Ian]

certain qualities of the lens need not have to be blown up to evaluate.

while one can't judge sharpness, one can clearly see the creamy bokeh on the above pixs.

Another issue is the out of foucs highlight. While many has complained that the Canon 180mm L produces objectionable octogeon highlights, the highlights produces by the Sigma is very nice.

any idiots can tell these lens properties just looking at the above pix.

1) Almost any lens will give you you inaccurately describe as a 'creamy bokeh' if the background is a considerable distance from the in-focus subject, that's the nature of a narrow zone of focus. Show me a backround that is 0.3-10cm behind the zone of focus before taking about bokeh with macro lenses. Also show a varied background that is a mixture of dark/light and blobs and lets see how it's real bokeh is.

2) Yes, idiots probably can tell much from your low resolution images, however advanced amateurs and professionals alike are too busy laughing in the corner at such a notion.

Also noted is the change in your second image on your earlier post ... I wonder why you changed it?

 

[kenghor]

Nice bokeh.

Ugly bokeh.

 

[kenghor]

I've taken enough images to see that the Sigma 180 macro has nice bokeh. The flower shot itself is enough to see how the different colors blend together.

For me, a non-advance and non pro, I'm able to see the differences from the above 2 jpg images. A professional / advance photog like u will perhaps need a professionally blown-up big print to tell the difference.

 

[kenghor]

Well, since only advanced amateurs and professionals like u like laughing at my jpg pictures, then I'll leave this thread and you can continue this discussion with WORDS.