Help! DA*16-50 not focusing at Infinity


GSiGuy

Senior Member
Sep 14, 2010
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Just noticed a problem with my DA*16-50.

When it hits infinity, i get no focus confirmation (blinking) and cannot take a shot...

At other distances less than infinity it seems ok.

The problem is not consistent. It is always present at larger apertures but seems less of a problem at smaller apertures.

Anyone know what is wrong and how to fix this?
 

Just noticed a problem with my DA*16-50.

When it hits infinity, i get no focus confirmation (blinking) and cannot take a shot...

At other distances less than infinity it seems ok.

The problem is not consistent. It is always present at larger apertures but seems less of a problem at smaller apertures.

Anyone know what is wrong and how to fix this?

You may need to send to Kevin, our fav tech guy at APD
 

Was it like this before or just started to behave like this? And which camera are you using? I know K5 has some problem with some lenses when focusing at infinity ...
 

You may need to send to Kevin, our fav tech guy at APD

Kevin is with APD now? Thought he leave Emjay to join Nikon auth dealer?

Was it like this before or just started to behave like this? And which camera are you using? I know K5 has some problem with some lenses when focusing at infinity ...

It just began to be like that. I haven't used the 16-50 for a few months though and just took it out.

I used a K-30.

Just noticed it after molesting a Sigma 18-35 and slapped the 16-50 back on...
 

if you use manual focus..can you focus to infinity?
 

if you use manual focus..can you focus to infinity?

Yes. Even on AF, the motor hits the infinity stop but i just can't get AF confirmation and shoot. Damn light just blinks.
 

Yes. Even on AF, the motor hits the infinity stop but i just can't get AF confirmation and shoot. Damn light just blinks.

I was thinking if you can get the focus beep on mf and not on af while focusing on the same subject..it cld be signs that sdm is failing.. Maybe you can get your lens check at apd just to be sure
 

Kevin is with APD now? Thought he leave Emjay to join Nikon auth dealer?



It just began to be like that. I haven't used the 16-50 for a few months though and just took it out.

I used a K-30.

Just noticed it after molesting a Sigma 18-35 and slapped the 16-50 back on...


He has been there for some time already. he also told me that we cannot keep a lens in the cabinet for too long without using it. Needs to exercise too like humans.
 

It just began to be like that. I haven't used the 16-50 for a few months though and just took it out.

I used a K-30.

Just noticed it after molesting a Sigma 18-35 and slapped the 16-50 back on...

Try with another camera and see if it behave the same, and try another 16-50 lens on your K30 too and see if it has the same focus problem. If you can join the outing, I'd be happy to share my K3 and 1650 ;)
 

He has been there for some time already. he also told me that we cannot keep a lens in the cabinet for too long without using it. Needs to exercise too like humans.

Good guy! If "self-help" does not solve my problem i'll go look for him.

I was thinking if you can get the focus beep on mf and not on af while focusing on the same subject..it cld be signs that sdm is failing.. Maybe you can get your lens check at apd just to be sure

Oic... ok i will go try it and see if that's the case.

Try with another camera and see if it behave the same, and try another 16-50 lens on your K30 too and see if it has the same focus problem. If you can join the outing, I'd be happy to share my K3 and 1650 ;)

Thanks for the offer, FengWei. When is the next outing?
 

Here's an update and a new problem to report...

The camera (inexplicably) is now able to allow me to take pics when focused at faraway objects. However, I noticed some softness in IQ, especially at 50mm.

Well, I took my K-3 out and shot the same scene and did notice (at least on the screen) a significant difference in IQ between the pics. It looks very sharp on the K-3 but much softer on the K-30. The difference is marked enough for me to suspect it doesn't lie with the sensors being different. I am beginning to suspect that the K-30 is actually not focusing at infinity although the focus confirmation beep does come on now and the camera allows me to actuate the shutter.

As the lens is still under warranty (but not my K-30), I am planning to bring both K-3 and K-30 down and show it to APD. Hopefully they can find the problem.
 

Here's an update and a new problem to report... The camera (inexplicably) is now able to allow me to take pics when focused at faraway objects. However, I noticed some softness in IQ, especially at 50mm. Well, I took my K-3 out and shot the same scene and did notice (at least on the screen) a significant difference in IQ between the pics. It looks very sharp on the K-3 but much softer on the K-30. The difference is marked enough for me to suspect it doesn't lie with the sensors being different. I am beginning to suspect that the K-30 is actually not focusing at infinity although the focus confirmation beep does come on now and the camera allows me to actuate the shutter. As the lens is still under warranty (but not my K-30), I am planning to bring both K-3 and K-30 down and show it to APD. Hopefully they can find the problem.

Maybe you can try one pic with AF and one with MF to infinity and see if the results are the same? Maybe k3 sensor really better than k30 haha :)
 

Maybe you can try one pic with AF and one with MF to infinity and see if the results are the same? Maybe k3 sensor really better than k30 haha :)

Thanks for the suggestion. I tried what you said but it's still looking somewhat soft on both MF and AF focus. I do note that the lens does indicate that it is on infinity when on AF...
 

hi GSiGuy,

Its sounds like the SDM is beginning to fail. This can easily be resolved by converting it to screw drive.

Cheers
 

hi GSiGuy,

Its sounds like the SDM is beginning to fail. This can easily be resolved by converting it to screw drive.

Cheers

You reckon? Hmmm... but focus on the K-3 seems spot on...
 

It's mainly due to the difference in AF system and accuracy..

Remember that the K3 AF system has more than 9 points in the central area in comparison to the K30.

In that sense, the K30 still has dinner-sized plate for its AF points therefore leading to it not being able to focus as accurately as K3.

Where the improved resolution due to the lack of AA filter, it shows up when you manually focus to infinity and notice that the K30 output is slightly softer than the K3.

In short, the K3 AF system and the lack of AA filter proves to be a plus point over the K30..
 

Did you send your lens for calibration with your K3 or K30 to APD before as you mention you will pay a visit to the service centre if all fails?

Possible to post the photo of your AF and MF on infinity for your K30 on the same subject?
and also the K3 AF one?

Just a thought it should help us understand more?
 

Did you send your lens for calibration with your K3 or K30 to APD before as you mention you will pay a visit to the service centre if all fails?

Possible to post the photo of your AF and MF on infinity for your K30 on the same subject?
and also the K3 AF one?

Just a thought it should help us understand more?

Think it'll definitely need to be linked to a full-res photo, if not web compressions won't show much difference.