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02-15-2010, 02:38 PM   #1
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Sigma 18-250mm OS HSM

About a month ago I got the Sigma 18-250. Due to crappy weather I haven't done much with it, but here is a representative shot I did Yesterday. It was 7 degrees with about a 35 MPH wind, so I was in a bit of a hurry. I'm pretty happy with the IQ so far. This was at 32mm, RAW processed with LR 2.6






Here's a crop without PP. Conversion only ACR Defaults.




Last edited by Parallax; 02-15-2010 at 03:25 PM.
02-15-2010, 04:25 PM   #2
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Holy Gaggle of Geese Batman!

Thanks for sharing ... I'm saving for a lens pruchase and this is one of my "fringe" choices that I just might end up getting. Please continue sharing!
02-15-2010, 07:19 PM   #3
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I have to ask....unless there is a nuclear reactor nearby dumping hot water, how is it that pond has no ice in 7 degree weather? Its been 60 all week until today??
02-15-2010, 07:39 PM   #4
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QuoteOriginally posted by imtheguy Quote
I have to ask....unless there is a nuclear reactor nearby dumping hot water, how is it that pond has no ice in 7 degree weather? Its been 60 all week until today??
It is heated. Just to the left of that brick building there is a waterfall of sorts with a large gas flame under it and the water constantly circulates. There may be other heat sources as well; I'm not sure.

02-15-2010, 07:45 PM   #5
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QuoteOriginally posted by Parallax Quote
It is heated. Just to the left of that brick building there is a waterfall of sorts with a large gas flame under it and the water constantly circulates. There may be other heat sources as well; I'm not sure.
Wow. I know the waterfowl appreciate that.
04-13-2010, 04:21 AM   #6
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Is there somewhere a review from this lens ?
04-13-2010, 04:33 AM   #7
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QuoteOriginally posted by netuser Quote
Is there somewhere a review from this lens ?
Sigma Lens: Zooms - Sigma 18-250mm f/3.5-6.3 DC OS HSM (Tested) - SLRgear.com!
04-13-2010, 05:54 AM   #8
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I've learned that I am happier with the kit lens or even the DA17-70 if I use them as if they were about 5mm shorter. Test results for the Sigma are interesting to me because they tend to confirm the issue with superzooms in general. They are generally not all that great at the long end, and why carry around extra glass that may not get you a whole lot more than cropping a shorter, sharper lens?

The shot Jim posted may also make that point. This lens is sharp enough around 35mm, that a pretty decent crop was possible. I wonder how a 30% crop from, say 70-80mm would compare to a full APS-c frame shot at 250?

04-13-2010, 07:29 AM   #9
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QuoteOriginally posted by GeneV Quote
I've learned that I am happier with the kit lens or even the DA17-70 if I use them as if they were about 5mm shorter. Test results for the Sigma are interesting to me because they tend to confirm the issue with superzooms in general. They are generally not all that great at the long end, and why carry around extra glass that may not get you a whole lot more than cropping a shorter, sharper lens?
I don't have a Sigma, I have the DA 18-250 and my tests showed it as slightly sharper than my 18-55mm. It's very sharp (for a zoom) up to 150mm and decently sharp up to 250mm. There's no way you could crop a kit lens or 17-70 and get anywhere near the long end resolution of the 18-250.

The 18-55 beats the 18-250mm for distortion and vignetting on the wide end, and those are easily corrected.

Last edited by audiobomber; 04-13-2010 at 07:45 AM.
04-13-2010, 08:43 AM   #10
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QuoteOriginally posted by Parallax Quote
I'm pretty happy with the IQ so far. This was at 32mm, RAW processed with LR 2.6

Here's a crop without PP. Conversion only ACR Defaults.
I assume you focussed on the near edge of the pond? This crop looks like it suffers from oof blur.
04-13-2010, 09:36 AM   #11
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QuoteOriginally posted by audiobomber Quote
I don't have a Sigma, I have the DA 18-250 and my tests showed it as slightly sharper than my 18-55mm. It's very sharp (for a zoom) up to 150mm and decently sharp up to 250mm. There's no way you could crop a kit lens or 17-70 and get anywhere near the long end resolution of the 18-250.

The 18-55 beats the 18-250mm for distortion and vignetting on the wide end, and those are easily corrected.
The Photozone test of the DA18-250 was considerably more favorable than the test of the Sigma posted above.

I don't have much use for the 250mm focal length unless I am shooting wildlife (and then it is often too short). I don't have an 18-250 to see how much better or worse, say a 50% crop of a DA17-70 at 65 mm would be than the zooms at 130mm, or a crop of a prime like the DA70 or FA77 (which I always have along) compared the superzoom at 150mm. From the review, it sounds like the Sigma might not win that comparison with either the prime or the zoom. Have you tried any comparison like this?
04-13-2010, 10:12 AM   #12
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I have a Sigma 17-70 that is my usual walkaround lens, and I have the 18-250 that I bought prior to a vacation at the end of last summer.

If you have situations where you can only choose ONE lens for an extended period, the Sigma 18-250 is an excellent candidate. It was indeed the only lens I brought on that trip, and the entire time, the lens never really left me dissatisfied.

The weather conditions, on the other hand, did... Everything was hazy due to the California wildfires last August.
04-13-2010, 01:37 PM   #13
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QuoteOriginally posted by GeneV Quote
I don't have an 18-250 to see how much better or worse, say a 50% crop of a DA17-70 at 65 mm would be than the zooms at 130mm, or a crop of a prime like the DA70 or FA77 (which I always have along) compared the superzoom at 150mm. From the review, it sounds like the Sigma might not win that comparison with either the prime or the zoom. Have you tried any comparison like this?
I had another test to do so I did something like what you're describing. I cropped a D FA 100mm macro shot to the same fov as the fully extended 18-250. Frankly I was a bit surprised at the results. The prime shot looks quite a bit better, mostly due to better colour and contrast. Unfortunately even with a pixel-rich K20D, resolution drops from 14.5mp to 2.3mp. IOW, fine for computer viewing, but not suitable for printing. For cameras with fewer pixels or lenses with less reach than the 100mm, things would only get worse. The 18-250mm shot could be punched up in p-p. The missing pixels OTOH are irreplaceable.

Last edited by audiobomber; 04-13-2010 at 01:43 PM.
04-13-2010, 01:41 PM   #14
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These are some of the better samples that I've seen from this lens.

How heavy would you consider it to be because of the long range and the OS?
04-13-2010, 05:04 PM   #15
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QuoteOriginally posted by audiobomber Quote
I had another test to do so I did something like what you're describing. I cropped a D FA 100mm macro shot to the same fov as the fully extended 18-250. Frankly I was a bit surprised at the results. The prime shot looks quite a bit better, mostly due to better colour and contrast. Unfortunately even with a pixel-rich K20D, resolution drops from 14.5mp to 2.3mp. IOW, fine for computer viewing, but not suitable for printing. For cameras with fewer pixels or lenses with less reach than the 100mm, things would only get worse. The 18-250mm shot could be punched up in p-p. The missing pixels OTOH are irreplaceable.
I was thinking about a 50% crop, and not going all the way to 250mm. That would leave about 4.5mp. You can make better prints than you would think from 2.3mp. I made nice A4 prints from a 3mp Coolpix.
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