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11-17-2012, 11:24 AM   #1
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Update on my DA 55 1.4 from adorama

I got the lens yestarday like I reported on the other thread, I'm not an expert in how to test a lens formally but I've found the lens is back focusing, af fine adjustment of -8 - 10 helps a lot, but even then it still misses sometimes.

ALso I find it almost unusable at 1.4 , my takumar 50 1.4 is much sharper at 1.4, missfocus and I knew it was gonna be soft but the amount of purple fringing is off the hook. Pretty sharp from 1.8 on when in focus.

My d fa 100 wr leaves this lens on the dirt when it comes to af accuracy and the focusing on that lens is pretty slow , that doesn't bother me, I just want accuracy.

Should I send the lens back :/ and is is supossed to be softer than a the tak at 1.4

11-17-2012, 11:48 AM   #2
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Sounds like you got a dud, sorry.
11-17-2012, 11:58 AM   #3
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how is in focusing in LV, if is same You have lemon
11-17-2012, 12:05 PM   #4
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QuoteOriginally posted by Vindemiatrix Quote
I got the lens yestarday like I reported on the other thread, I'm not an expert in how to test a lens formally but I've found the lens is back focusing, af fine adjustment of -8 - 10 helps a lot, but even then it still misses sometimes.

ALso I find it almost unusable at 1.4 , my takumar 50 1.4 is much sharper at 1.4, missfocus and I knew it was gonna be soft but the amount of purple fringing is off the hook. Pretty sharp from 1.8 on when in focus.

My d fa 100 wr leaves this lens on the dirt when it comes to af accuracy and the focusing on that lens is pretty slow , that doesn't bother me, I just want accuracy.

Should I send the lens back :/ and is is supossed to be softer than a the tak at 1.4
I am a bit confused; if your lens is back focus, wouldn't you do a +8 or +10 instead of -8 or -10? I could be wrong...

11-17-2012, 12:56 PM   #5
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QuoteOriginally posted by aleonx3 Quote
I am a bit confused; if your lens is back focus, wouldn't you do a +8 or +10 instead of -8 or -10? I could be wrong...
You are right sorry, i meant +8 +10.

after more shoots nails focus in some , really bad in others, I don't have any problems with my other lenses so I don't think is the camera.

Looks like is going back
11-17-2012, 01:55 PM   #6
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Under which light conditions are you testing your lens? If you are doing it in a low light situation, the AF might have some trouble nailing the focus. The best way to do this is with a tripod and daylight.
11-17-2012, 03:52 PM   #7
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I had the exact same experience with my first DA*55 which was promptly returned. i mean the exact same symptoms.....

Return it.

I got a second copy a couple months later from a different vendor and it is right on. I'm not saying anything against Adorama of course - these lenses seem to have this problem as I've read about a lot of people exchanging copies - as many as 4 copies to get a good one. I consider myself lucky to get a perfect one on the second try.

I would talk to Adorama - since you bought it as a "floor model", I know they will not give you any problem at all in the return process, but maybe you can try to get them to send you a new one for the same price for your trouble. Worth a shot?
11-17-2012, 04:33 PM   #8
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QuoteOriginally posted by Davidw0815 Quote
Under which light conditions are you testing your lens? If you are doing it in a low light situation, the AF might have some trouble nailing the focus. The best way to do this is with a tripod and daylight.
Test conditions...that is always the bugger.

If one is going to bother with the AF adjust, it is best to do so with a consistent setup that makes it simple for the AF to lock.
  • On tripod
  • Use a moderate distance from subject (say 20x-40x the focal length)
  • Flat subject parallel to sensor plane
  • High contrast subject (newspaper classified ads or lens test target attached to flatboard with contact cement)
  • Consistent light
  • Use single point AF
If you are testing for forward/back focus:
  • Do an initial AF exposure
  • Disable AF and make a single exposure at each of several set points forward/backward from the original AF exposure. A focus rail is helpful here.
Repeat the above several times making exposures at the same set points as a precision test. It may well be that the system is properly dialed in (accurate) but is simply too imprecise for the intended use. If precision is not an issue, the same distance increment will be consistently better across trials. Again, it is important to do the test with a flat target that is easy for the system to lock on. You want to present the best case scenario. After all, calibration is your goal.

If the system is too imprecise to calibrate (no distance is consistently good), the cause might be a design limitation of the AF system (not good enough for use with a fast lens?) or a manufacturing flaw. A differential diagnosis would require testing with a known good lens of the same model.

Sound like too much trouble? It may well be, but after going through the experience, I can guarantee that the user will have a very good notion of how well the system is performing under ideal circumstances and what can be expected from tweaking the AF bias.


Steve

11-17-2012, 05:08 PM   #9
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QuoteOriginally posted by Davidw0815 Quote
Under which light conditions are you testing your lens? If you are doing it in a low light situation, the AF might have some trouble nailing the focus. The best way to do this is with a tripod and daylight.

No, not at all. daylight and tripod, horrible pf too in this conditions.
11-17-2012, 05:27 PM   #10
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It really didn't take an expert to know something was wrong with the lens. I tried the lens in the way is described above. I have fast lenses and had fast lenses my canon so I know what to expect as far as dof and sharpeness wide open but for this lens it was unaceptable and just wrong.

The pictures were good when in focus small apertures and no sunlight. Otherwise and out of focus pf soft mess.

I will definetely get another copy.
11-17-2012, 06:31 PM   #11
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If you search through past postings, and in the lens review comments, many, many of the DA*55 need +8 to +10 -- including the copy I bought new in April of 2012.

Since mine is still under warranty, I will send it to CRIS for repair before . I understand they are familiar with this problem.

Not sure if yours would be covered by warranty since it is a floor model ....
11-17-2012, 06:56 PM   #12
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QuoteOriginally posted by Tanzer Quote
If you search through past postings, and in the lens review comments, many, many of the DA*55 need +8 to +10 -- including the copy I bought new in April of 2012.

Since mine is still under warranty, I will send it to CRIS for repair before . I understand they are familiar with this problem.

Not sure if yours would be covered by warranty since it is a floor model ....

I already sent it back .
I'm gonna end up paying full price for one, I'm to shy to call adorama and ask them about a new at the same price lens LOL
11-17-2012, 07:04 PM   #13
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QuoteOriginally posted by Vindemiatrix Quote
I already sent it back .
I'm gonna end up paying full price for one, I'm to shy to call adorama and ask them about a new at the same price lens LOL
Well don't give up - once you get a good copy I'm sure you will love it.
11-17-2012, 07:40 PM   #14
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Call them, they're very attentive. I bought a new K5 from them only to discover it had been used. I made mention and was readily engaged by their service rep named Helen. Things were worked out. Call them.
11-19-2012, 10:34 AM   #15
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I called B & H today. I asked what's the price of the lens and he said $594 brand new, without me having to ask or anything.., so I ordered one.
The guy at adorama told me the $599 was for the floor model only, after I asked for a better price.
I hope I have better luck with this lens. And that adorama refunds my money or I'll be in the deep LOL
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