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07-05-2008, 10:48 PM   #1
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To DA 14mm owners

Is your copy soft wide open at 2.8 and does the focusing ring keep turning past the closest focusing range and infinity? My images at 2.8 almost seem to have this like "glow" on them. Maybe I'm expecting too much out of this ultra-wide prime but I think something is wrong with the one I got a few days ago It does seem sharp stopped down and I managed to take some nice fireworks shots like the one below but I would like to hear from others who have this lens as well.



07-05-2008, 10:57 PM   #2
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Well, I think the "glow" as you put it is from the 4 sec exposure time. Also, your aperture is listed at f11 on the above shot. However, that gave a nice effect. Did you shoot any with your DA 50mm f1.4?
07-05-2008, 11:54 PM   #3
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I think you are experiencing sensor bloom. Not a problem specific to Da 14mm
07-06-2008, 08:22 AM   #4
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The focus ring is not directly coupled so it will turn in either direction forever, but gets stiff when you're out of range. That is normal for all lenses whose focus ring does not turn in AF mode.

Also, mine has a tendency to BF which could give you a bit of a glow. I keep mine focused about 1mm short of the infinity mark and I rarely move it off.

07-06-2008, 01:52 PM   #5
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Like jslifoaw said, glow could be the bookeh of objects between camera and focal plane meaning you or your camera backfocused.
I have the lens and focusing ring works just like yours. I was suprised at the begining as well.
07-06-2008, 05:38 PM   #6
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QuoteOriginally posted by sharko Quote
Is your copy soft wide open at 2.8 and does the focusing ring keep turning past the closest focusing range and infinity?
This is the operation of the focus clutch mechanism. The focus clutch mechanism is designed to allow you to manually focus *whilst* you are using the AF. The focus system in the lens has a clutch set up and therefore this allows some "slippage" past either end of the focus limits, ie minimum focus and maximum focus. If you try to focus as normal AF lens that doesn't have the focus clutch system, then you would damage the AF motor.


QuoteQuote:
My images at 2.8 almost seem to have this like "glow" on them. Maybe I'm expecting too much out of this ultra-wide prime but I think something is wrong with the one I got a few days ago It does seem sharp stopped down and I managed to take some nice fireworks shots like the one below but I would like to hear from others who have this lens as well.

The glow is probably attributed to sensor bloom, as others have suggested, and is not necessarily a lens problem. I have never had any issues with my DA14 and it is one of my most utilised lenses. It does get sharper stopped down as you say, but this is pretty much the same for all lenses.

Are you sure it is focusing on the correct spot? Don't forget that at f2.8 you will have a shallow DOF and you need to get your focus spot on.
07-06-2008, 07:34 PM   #7
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The DA14 is a pretty sharp lens even wide open, even when shooting at distant target. I went to KL Malaysia one week back w/ a defected K100D (could only take photos wide open) and my DA14, took some wide open shots like these:





Here is a full size original photo of the above one:
http://www.eng8.nus.edu.sg/FileStorage/Frank/Photos/KL_Malaysia2008/IMGP0141_p.jpg
07-06-2008, 07:46 PM   #8
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QuoteOriginally posted by sharko Quote
Is your copy soft wide open at 2.8 and does the focusing ring keep turning past the closest focusing range and infinity? My images at 2.8 almost seem to have this like "glow" on them. Maybe I'm expecting too much out of this ultra-wide prime but I think something is wrong with the one I got a few days ago It does seem sharp stopped down and I managed to take some nice fireworks shots like the one below but I would like to hear from others who have this lens as well.
It looks to me as if focus is on the fence, not the fireworks. Manual focus is the way to go with shots like this.

07-06-2008, 10:43 PM   #9
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QuoteOriginally posted by frank Quote
The DA14 is a pretty sharp lens even wide open, even when shooting at distant target. I went to KL Malaysia one week back w/ a defected K100D (could only take photos wide open) and my DA14, took some wide open shots like these:





Here is a full size original photo of the above one:
http://www.eng8.nus.edu.sg/FileStorage/Frank/Photos/KL_Malaysia2008/IMGP0141_p.jpg
Both fantastic shots, Frank! The first one is awesome!
07-06-2008, 11:59 PM   #10
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Thank you everyone for their replies. It's definitely a relief to find out that the focusing ring continually turning is not an issue. I thought that would be the cause behind the softness but I guess its just a matter of learning to work with the lens since the field of view is so wide and the focusing point with a large aperture is going to be very small.
07-08-2008, 04:21 AM   #11
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QuoteOriginally posted by sharko Quote
Thank you everyone for their replies. It's definitely a relief to find out that the focusing ring continually turning is not an issue. I thought that would be the cause behind the softness but I guess its just a matter of learning to work with the lens since the field of view is so wide and the focusing point with a large aperture is going to be very small.
Not only is the focusing ring turning forever not an issue, but you may find that it hits its "hard stop" a bit after the marked point for infinity. This is to allow the lens to autofocus past infinity, which is allowed in case the lens falls out of alignment and "actually" focuses to infinity beyond infinity on the barrel. This threw me the first time I encountered it and manually turned the focus ring until I hit tension, and I found the entire image soft. On such AF lenses, using AF on a faraway object is often the best way to ensure focus. The barrel may indicate misfocus, but if the AF system is good and it finds focus, you can ignore the barrel.
07-08-2008, 09:21 AM   #12
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QuoteOriginally posted by sharko Quote
Thank you everyone for their replies. It's definitely a relief to find out that the focusing ring continually turning is not an issue. I thought that would be the cause behind the softness but I guess its just a matter of learning to work with the lens since the field of view is so wide and the focusing point with a large aperture is going to be very small.
For most subjects at distances further away than a couple of meters, you can forget AF. Just set the focus manually at infinity or (depending on the chosen apertures) at the hyperfocal distance and everything within the depth of field will be sharp. This is one of the advantages of wide angle lenses and the recipe for those famous condid shots of street photographers over the decades. You can push the shutter release button whenever you wish and do not need to choose an AF target nor wait until the camera has focused.

I use my old 15/3.5 most of the time in this pre-focused mode. (It has no AF anyway, but that's not a loss with an extreme wide angle.)

Night time shots as yours, should be focused manually anyway. But looking through the viewfinder is a better way to do so, than looking on scale marks.

Ben
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