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05-19-2011, 09:48 PM   #1
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Is this a big problem with my DA 12-24?

Hey guys, I just bought a used DA12-24 f/4 for $600 (including a 3 year warranty with the store I bought it from, Henrys).

When I checked the aperture blades however, I think they do not fully open up when I flick down the little lever for the aperture blades on the back of the lens. Bellow is a picture of what I am talking about.

Is this normal for this lens? If it is a defect, is it big enough for me to return to the store? Or should I keep it because I got a good deal? The lens retails for around $1000 in Canada.

Name:  lens4.jpg
Views: 404
Size:  3.2 KB

Thanks for your help!

05-19-2011, 09:55 PM   #2
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Compare the exposure at f/4 to another lens. Is it the same? If it really is stuck and doesn't fully open, then you won't have an f/4 lens but an f/8 or f/11...
05-19-2011, 09:55 PM   #3
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Looks OK to me.... remember you are looking at a lens with a maximum aperture of 6mm (24 / 4), this isn't a 85mm f/1.4 portrait lens after all.
05-19-2011, 09:56 PM   #4
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Here are some bigger pictures:

Name:  photo 1(2).jpg
Views: 329
Size:  44.1 KB
Name:  photo 2(2).jpg
Views: 349
Size:  29.5 KB

05-19-2011, 09:58 PM   #5
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I know the aperture is f/4 and not f/1.4 or f/2.4 but when I open the aperture blades on my da50-200 at 200mm, which is f/5.6 I believe, they still fully open up and I cant see the blades at all.
05-19-2011, 10:00 PM   #6
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200 / 5.6 = 36mm aperture
24 / 4 = 6mm aperture

big difference.....

Notice that the aperture numbers on the lens are expressed as f/5.6 (ie focal length divided by 5.6)
05-19-2011, 10:01 PM   #7
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QuoteOriginally posted by twitch Quote
200 / 5.6 = 36mm 24 / 4 = 6mm big difference..... ______________
soooo the lens is fine? lol
05-19-2011, 10:15 PM   #8
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I don't have this lens but some constant zooms would stop down the aperture as it zooms to maintain the constant aperture. If that's the case with your lens, then it should open up fully at 24mm.


Last edited by wlachan; 05-19-2011 at 10:41 PM.
05-19-2011, 10:19 PM   #9
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Btw, I am zoomed out to 12mm in these pictures.
05-19-2011, 10:39 PM   #10
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Zoom to 24 mm?
05-19-2011, 10:43 PM   #11
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Just looked at my 12-24, and it looks the same as yours.
05-19-2011, 11:08 PM   #12
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I just zoomed in at 24mm and the blades open up completely, I took two more pictures, The first one is at 24mm and the second at 12mm. So I am assuming the lens is okay?

At 24mm:

Name:  photo 1(3).jpg
Views: 333
Size:  92.1 KB

At 12mm:

Name:  photo 2(3).jpg
Views: 326
Size:  78.3 KB
05-19-2011, 11:09 PM   #13
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QuoteOriginally posted by mokey Quote
Just looked at my 12-24, and it looks the same as yours.
That's a relief. Thanks for checking
05-19-2011, 11:13 PM   #14
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Too bad it couldn't be overridden at 12mm, who knows, at wide open it could be a 3.5 or even a 2.8!
05-19-2011, 11:47 PM   #15
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QuoteOriginally posted by Chex Quote
Too bad it couldn't be overridden at 12mm, who knows, at wide open it could be a 3.5 or even a 2.8!
You should remove your aperture blades and tell us what happens when you shoot at 12mm @f2.0
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