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02-11-2012, 11:57 AM   #1
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Problem with DFA100 macro wr

Hello

sometime ago i noticed that many of pictures with my dfa are overexposed, especially from 5.6 and above, so i did a quick test using av mode and i noticed that every photo above 5.6 overexpose being worst on smaller apertures f11 f16.
I have checked the aperture blades and i noticed they close very slow in comparision with every other lens i have.
Luckly i can return to amazon for a refund, but here is my problem
is this something common with this lens? i want repurchase this lens, but being an amazon international customer is not a easy task return something when it goes wrong,
i was thinking in the tamron 90 macro instead

what do you think?

02-11-2012, 12:00 PM   #2
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I like the Tamron 90, so I'm guessing it's just as good IQ but if you can afford the 100, it's better build quality and WR. You must have a defective lens. You need to return it. For the cost of that lens it has to be worth your while to jump through the hoops.
02-11-2012, 12:03 PM   #3
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I've not had that problem with mine.
02-11-2012, 12:46 PM   #4
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I remember photozone having a simlar problem with a lens they tested. Im not sure but it may have been the 60mm tamron.
They were suspicious when used wide open the results were poor but got better when stopped down. except the lens was still
producing superb results even at F11 which is strange because this is where defraction starts to take its toll and starts to degrade.
Stranger still, when used on a diffrent camera it actually whent slightly the opposite way. apparently there is a differance in how cannon and
Nikon work in stopping down lenses. The lens was faulty though and it seemed the displayed aprature was actually larger than it should have been.
hence, the lens seemingly to perform great even at F22. This kind of sounds like it could be the same problem.

02-11-2012, 01:33 PM   #5
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I haven't had a problem with mine and have had it since it was released. The way the lens is built I would have thought it would be much better than most as it is metal. I think the lens will outlast me. I wouldn't see a problem in returning or using your warranty.
02-11-2012, 01:42 PM   #6
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come on - the only answer to your question can be that is is not supposed to happen with that lens.Have it replaced.
If the Tamron has a focus limiter... that would be a reason to get one over the Pentax, but then the Pentax is weather sealed and allow AF override.
02-11-2012, 01:54 PM   #7
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Original Poster
thank you.
i will give another chance to the dfa100 then.

i tested the aperture blade lever (?) in the mount and in every other lens the lever move easy and close really quick, but in the macro the lever feels really tight and when i released it took almost a second to close, so i guess the camara could not completely close the aperture then i got a overexposed image
02-11-2012, 10:41 PM   #8
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QuoteOriginally posted by Sekul Quote
thank you.
i will give another chance to the dfa100 then.

i tested the aperture blade lever (?) in the mount and in every other lens the lever move easy and close really quick, but in the macro the lever feels really tight and when i released it took almost a second to close, so i guess the camara could not completely close the aperture then i got a overexposed image
Yeah, that's one of the quick tests whenever you have overexposure issues. Sounds like a trip to service is in the future.

02-12-2012, 07:03 AM   #9
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I have a DA 40 Limited that has sticking aperture blades in cold weather. I have pretty much the same results, overexposed shots. Bringing it back inside cures it for now but it's going in for repair soon. Your lens is probably behaving similar. Are you shooting on a camera with live view? Engage the DOF preview and that will tell you right off whether the lens is stopping down or not.
02-12-2012, 01:24 PM   #10
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QuoteOriginally posted by reeftool Quote
I have a DA 40 Limited that has sticking aperture blades in cold weather. I have pretty much the same results, overexposed shots. Bringing it back inside cures it for now but it's going in for repair soon. Your lens is probably behaving similar. Are you shooting on a camera with live view? Engage the DOF preview and that will tell you right off whether the lens is stopping down or not.
i did not use liveview but i did use the optical dof preview and i noticed that it take a while stopping down.
anyway, tomorrow i will order a new one
02-17-2012, 04:59 PM   #11
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Just to end this, today i recieve my new copy of the DFA100 WR, and now zero problem, the aperture blades close really qucikly and no overexpose at all f8.
03-25-2016, 02:52 AM   #12
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QuoteOriginally posted by Sekul Quote
Hello

sometime ago i noticed that many of pictures with my dfa are overexposed, especially from 5.6 and above, so i did a quick test using av mode and i noticed that every photo above 5.6 overexpose being worst on smaller apertures f11 f16.
I have checked the aperture blades and i noticed they close very slow in comparision with every other lens i have.
Luckly i can return to amazon for a refund, but here is my problem
is this something common with this lens? i want repurchase this lens, but being an amazon international customer is not a easy task return something when it goes wrong,
i was thinking in the tamron 90 macro instead

what do you think?
I have exactly the same problem right now with newly received from Amazon. Should I return this or is there any way I could do by myself to solve this?
03-25-2016, 04:43 AM   #13
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QuoteOriginally posted by Sekul Quote
is this something common with this lens?
It's not a common problem. It happens, rarely, with older lenses (think 30-40 years old). Get it replaced or repaired.
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