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09-19-2009, 01:35 PM   #76
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09-19-2009, 06:33 PM   #77
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beautiful shots - love the warehouse "look"
09-20-2009, 12:09 AM   #78
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WAUW !!

guidoanselmi #1 and #3 are AMAZING
09-20-2009, 02:15 AM   #79
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thanks! i'm going on a weekend hike though sequoia national park (a bit north of LA) next weekend. i'll probably post a few from there.

09-20-2009, 12:38 PM   #80
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Wow! Are those pictures from the Station Fire? Certainly spectacular shots, scary too.
09-20-2009, 09:32 PM   #81
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I was searching for photos taken with this lens on pbase and found some wonderful winter landscape photos here divers hivers Photo Gallery by Pascal Tritten at pbase.com

I was all set to buy this lens until I saw the price.. $1,200
09-20-2009, 10:19 PM   #82
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This lens came in extremely helpful during a recent trip to the Smithsonian Air & Space museum.
09-21-2009, 02:17 AM   #83
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QuoteOriginally posted by shemazar Quote
Theoretically, there's a big difference in the FoV from 10mm and 12mm, but when looking at the specs between the two lenses, the Angle of View (not to be confused with FoV - field of view). The angle of view between them is only 3.4 degrees by spec sheets.
That's very odd. Theoretically (using trigonometry, not linear scaling), the difference in AOV should ~10 degrees.

The 102.4 - 63.8 specified for the Sigma 10-20mm F3.5 are very close to my theoretical values (~ 100.4 - 62).

However 12-24mm should result in ~90 - 53 degrees, not in the 122 - 84.1 degrees specified for the Sigma 12-24mm F4.5-5.6 or the 99 - 61 degrees for the Pentax DA 12-24mm F4.0.

The fact the the two 12-24 lenses are specified with rather different AOV is further evidence to something being a bit odd.

I would expect the Sigma's 10mm to give a considerably wider view then the Pentax' 12mm, not just a mere 3.4 degrees.

BTW, I calculated the angle being formed by the wide (horizontal) dimension of the image only (which is consistent with the wikipedia definition of AOV). Perhaps others use a different basis.

09-21-2009, 07:22 AM   #84
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Angle of view is often used interchangeably with field of view and is most often measured diagonally. Pentax and Nikon quote the same diagonal angle of view of 99 to 61 degrees.

Actual angle of view will be different depend on the camera image sensor size. Important to note that Sigma quotes their angle of view based on their Sigma SD camera format. Typically speaking, a 10mm wide angle has about 9 degrees more coverage (diagonally) than a 12mm lens.
09-21-2009, 05:36 PM   #85
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QuoteOriginally posted by creampuff Quote
Angle of view is often used interchangeably with field of view and is most often measured diagonally.
It shouldn't be used interchangeably because AOV is measured in degrees whereas FOV is measured in meters. But the two are very closely related of course.

Not sure about the "most often" but the 99 - 61 degrees for the 12-24mm make sense when assuming the APS-C sensor diagonal. The 10-20mm figures assuming the same diagonal would then be 109 - 70.

In both cases, assuming the sensor width and the sensor diagonal, the theoretical difference between 10mm vs 12mm is ~ 10 degrees (as you also wrote).

The unexpectedly small difference between 10mm and 12mm as per manufacturer figures can thus be explained by using different bases (in this case probably due to different sensor sizes rather than "horizontal vs diagonal measurement"). The 102.4 - 63.8 degrees of the Sigma 10-20mm are consistent with the Sigma Foveon sensor diagonal of ~24.9mm.

BTW, the 122 - 84.1 degrees specified for the Sigma 12-24mm F4.5-5.6 are consistent with assuming a full frame sensor diagonal, which makes sense as this lens covers full frame.

Last edited by Class A; 09-21-2009 at 05:56 PM.
02-17-2011, 10:16 PM   #86
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Long time, no posts...


Last edited by SpecialK; 03-29-2011 at 08:44 PM.
03-29-2011, 08:46 PM   #87
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I got 4 Limiteds a little while back and have been using them a lot, but I'm not giving up the 12-24 :-)

03-30-2011, 03:19 PM   #88
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South Dakota Badlands
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03-30-2011, 03:35 PM   #89
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Nice photos guys. Good to see this thread resurected.
03-30-2011, 04:07 PM   #90
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Here's my own contribution; B&W HDR from 3 exposures @ 12mm (+/- 2 EV)

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