Sigma 70200/2.8 review by DK?

[vtube]

http://content.yudu.com/Library/A17sxb/ ... id%3D14917" onclick="window.open(this.href);return false;

Is DK = David Kilpatrick?

Quite bad comments for Sony 70200/2.8 (that I own).

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Andrea Olivotto
http://www.andreaolivotto.com" onclick="window.open(this.href);return false;

[David Kilpatrick]

Yes, that's me. The SAL 70-200mm f/2.8 has a lot in common with the Nikon 70-200mm f/2.8 AF-S, being designed apparently to get the most out the centre of the frame. Where the Nikon displays fairly bad loss of sharpness to the edges even at longer distances, it really only shows up on the Minolta/Sony design at close focus. There has been one thread here with an example photo posted to see whether a lens was faulty, and I was able to identify the issue straight way - the curved field of the SAL 70-200mm at 200mm, f2.8 and minimum focus results in really serious blurring in the outer part of the field.

I don't think the Sigma is quite as sharp as the SAL 70-200mm centrally, at any aperture-for-aperture comparison. But it's much sharper into the corners for close-up work, and that includes portraits, on full frame. I have been using it now for a couple more shoots and I am very happy with the results. Focus is accurate on the A900, there has been no need for CA correction unless 150-200mm range is used. I sold my Minolta 70-200mm (not a SAL version) and 2X Apo D converter after minimal use, mainly because of a few tests I did which disappointed me with the converter, and the general issue with close-up field flatness. I tend to use this type of lens a lot for close-up details.

However, it was not sold to buy the Sigma! It was sold because I preferred the 70-300mm G SSM. And it was only sold after I got the A900, because I had never used the lens on film only on APS-C format, so I had never seen the problems at maximum close-up magnification. I tested the Tamron (on Canon EOS 50D, a rather demanding resolution) and liked it but not enough to want one, the focus was very slow - and this was also a problem with the Minolta, really smooth focus but actually not as fast as my vintage 70-210mm f4 beercan for picking up on a moving subject.

Our son Richard runs the Sigma UK user website, and uses Nikon D3. He also gets the Sigma lenses to try out. He got the new 24-70mm HSM Sigma and when he brought it to show me, we both thought the performance was very poor for a £700 lens. The edges just were not good enough, it seemed to be made for APS-C. So he got a second copy, and this was the same. He's having to be very diplomatic in commenting about this lens, and sent sample files to Sigma's technical staff - they also are not happy with what he got on the D3. He kept his old 28-70mm f/2.8 having planned to buy the 24-70mm. It may be a clunky old direct drive focus type, but it's really sharp. For comparison, he brought along the new 70-200mm HSM in Nikon mount with the second 24-70mm sample. We lined up some tests, and I had not even planned to look at this lens - I thought it would just be an OK fast tele zoom updated for HSM.

After seeing the tests off the Nikon, I called Sigma and ordered one for Alpha. I had to wait over a month for the lens to come in stock. I was really surprised by the focus speed - maybe it's not twice a fast as the SAL, but it's certainly much faster, identical to the speed the Nikon version achieves. And I've been knocked out by the optical quality, even at 1:3.5 repro ratio, which is better for close-ups than any of the current SAL zooms. A couple of days after getting it they had the new HSM-compatible converters in stock so I ordered one immediately. All I can say is that the Sigma+converter combo beats the Minolta+ApoD 2X for sharpness, flatness of field etc.

Unlike the Minolta, which I hardly dared take out of the office because it was such a beautiful looking lens and so easily damaged - and worth £1800 or more when I got it, though prices have fallen - I have simply started using the Sigma every day. It's looking a bit scruffy already, the Zen finish and rubber grips pick up dust and handling marks as easily as the Sony/Zeiss designs. But the 1m close focus, the focus speed, and general handling plus the affordable cost (no more than my 70-300mm G SSM) plus incredible 1.75X close-ups with the converter mean I'm using this more than the 70-300mm now.

David

[vtube]

Thanks David.

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Andrea Olivotto
http://www.andreaolivotto.com" onclick="window.open(this.href);return false;

[artington]

David, have you perchance compared the performance of the Sigma 70-200 HSM with the new 2x converter against the SAL 70-400?

[David Kilpatrick]

Judging from the few pix I took with the 70-400mm I don't think any teleconverter combo will match it. The contrast is higher than I would expect to get. But I haven't yet tried the 70-400mm 'properly' and it is possible I never will, Sony just isn't geared up to sending out lenses on demand.

Here is a shot from the Sigma at 200mm, not the closest focus, but closer than a portrait distance:



This was not taken like this seriously, I have no use at all for pix of birds of prey tethered to posts, but the rest of my family party was intent on handling some of the birds I took a few snaps - this just happened to need f2.8, others were f4 or f3.5. You can tell from a detail (focus locked and held on the eye before re-composing) a fair amount about the lens, and also about the problems the A900 has when confronted with fine detail - with sharpening for web applied (100/0.8/0) the feathers below the beak are already breaking up and aliasing, and they are not even the sharpest details - moiré threatens. This is at ISO 320, with no noise reduction of any kind, via ACR 5.4RC. Normally I use 25 luminance 50 colour NR on ISO 320 to avoid the very fine coloured noise which is also breaking up the image, and I also use no sharpening.



The full size pic is at http://www.pbase.com/davidkilpatrick/image/113037650" onclick="window.open(this.href);return false;, view Original. Chromatic fringes have been corrected at +35 Red/Cyan and Defringe all Edges. This can't correct some of the colour bokeh issues which the lens does have - in common with all Sigma fast lenses and zooms I have used. You can learn a fair amount about the residual aberration mix at full aperture of this lens from some of the smaller highlight details, the halo is fairly symmetrical and the image core is very sharp.

The Tamron is not so different from this but the halo is more sharply defined on many subjects, and bigger - at f2.8 the image is soft with a sharp core even at longer distances (the Sigma is a little better than this):



This is taken with Canon 50D at ISO 200, treated the same way for processing as the Alpha 900 bird shot above. The 50D is a horrible camera for low ISO image quality, as you can probably tell - while they kick in some impressive NR for high ISOs, it has a really rough ISO 200 and there is something about the way this extremely high res sensor renders detail that I simply don't like. Also, the Tamron has the most terrible bokeh and even worse 'colour bokeh' issues than the Sigma, as the glimpse of background in this shot shows. Stopped down it is very sharp in a 'wiry' Nikon-style way. The Sigma has wonderful bokeh, I've been processing a lot of pix and have not found a bad one yet.

I'll make another post with f/11 bokeh and detail from the Sigma. I am not posting a level 12 JPEG to pBase as the level of detail means it's over 13 megs despite being a very simple shot, so it will be level 10.

David

[David Kilpatrick]

OK, here is a shot taken at 90mm and f/11 - more typical conditons really:



The Highlight Recovery function has been used at 100 to pull in some brightly lit angled details. The full size image is on pBase at http://www.pbase.com/davidkilpatrick/image/113038521" onclick="window.open(this.href);return false; - view at full size, this uses 25 sharpening, no NR and no CA correction. The detail in the fabric of the tabard is incredible in the original, I do not know if JPEG 10 will allow it to be seen. Also, the poor guy was spraying his audience generously while announcing the next show:



Now that bokeh, for a focal length at the lower end of the range and f11 with a mid-distance subject, is not bad at all - this is processed with NO sharpening, and WITH luminance and chroma NR, because that helps the bokeh (and also gives a fair idea of a practical setup for using ISO 320 routinely on the A900). I hope this also helps A900 and A700 users understand why ISO 320 is so useful - we are now shooting everything on both cameras at ISO 320 or 160 because of the significant quality gain when processing these settings from raw, compared to 200 or 400.

Please do visit the full size of this shot on pBase. I don't think anyone can say the A900 lacks sharpness when you see the guy's skin, the fabrics, etc. And the Sigma in backlight without any CA or defringe correction is not bad at all for a £700 lens.

David

[artington]

Great, David, thank you very much for these. As you say the fabric detail is remarkable. Glad I wasn't standing in front of him! I agree your comments about the A900. I have recently purchased one and have been quite amazed by the quality and sharpness of the photos. As you said in another posting it really does offer MF quality and has finally cured my bias towards film.

If you do get the opportunity to try out the SAL 70400G I'm sure I shan't be the only one who would welcome your thoughts.

[peterottaway]

David, in the Master Photo Digital review of the Sigma 70-200 you mentioned an HSM version of the 15-30 zoom. Is there any indication as to when this may become available ?

I rather baulk at the price of the CZ 16-35 zoom and the Sigma 12-24 isn't quite what I want as most of my wide shooting is in the 18 to 28 range and I don't want to keep changing lenses.

[David Kilpatrick]

Sigma plans to convert the entire range to HSM for Sony quite slowly - I think it partly depends on how fast the existing inventory sells. For example, I wanted a 12-24mm and was told that I might as well buy (last autumn) because it could be a year or two before an HSM version appeared and it would be more expensive by 2009. The second has certainly come true. I was lucky with the 70-200mm HSM, they agreed to hold the price for me, it should have been another 15% more expensive in the delivery I had to wait for.

David

[Mike-Photos]

Now that bokeh, for a focal length at the lower end of the range and f11 with a mid-distance subject, is not bad at all - this is processed with NO sharpening, and WITH luminance and chroma NR, because that helps the bokeh (and also gives a fair idea of a practical setup for using ISO 320 routinely on the A900). I hope this also helps A900 and A700 users understand why ISO 320 is so useful - we are now shooting everything on both cameras at ISO 320 or 160 because of the significant quality gain when processing these settings from raw, compared to 200 or 400.

Hi David, two questions:
1) There's talk of setting LO -1 to further improve noise in shadows, on top of ISO320 - have you tried this?
2) Is ISO160 as good as ISO320 as far as RAW processing? If so, why not use 160 instead of 320? I haven't seen mention of this before.

[calpon]

I hope this also helps A900 and A700 users understand why ISO 320 is so useful - we are now shooting everything on both cameras at ISO 320 or 160 because of the significant quality gain when processing these settings from raw, compared to 200 or 400.



David

David,

Could you write up some more about this comment. I have seen you reference this one other time, but I could never find out any details and/or commentary on this. I always assumed that using the rounded ISO's would be the best to use. Also, does this translate to higher ISO as well. I shoot a great deal at ISO800 for lower light sports and wildlife and I am always looking for ways to improve IQ at higher ISO.

[artington]

David Kilpatrick wrote:

I hope this also helps A900 and A700 users understand why ISO 320 is so useful - we are now shooting everything on both cameras at ISO 320 or 160 because of the significant quality gain when processing these settings from raw, compared to 200 or 400.



David

David

I'd be interested in hearing more about this too.