[Russell-Evans]

If you're like me and had to save up to buy the DA* 50-135 (not a cheap lenes), expecting to get a Pentax QUALITY product and the autofocus failed at 13 months, (timed perfectly with losing my job and needing to hold back on spending), you would not think this problem is overblown.

I know you said you saved for the lens, but did you happen to pay for it with a credit card? The two credit cards I have automatically extend the warranty. The credit card might pick up the repair for you.

Thank you
Russell

[creampuff]

Well Russell, you're making a lot of assumptions with regards to your guesstimates on numbers. Even then, the absolute numbers of SDM failure don't appear high.

Anyway just so you know, the number of Pentax users in Singapore is most certainly greater than 50... (the pitfalls of making simplistic assumptions based on group photos posted)

[calicojack]

I know you said you saved for the lens, but did you happen to pay for it with a credit card? The two credit cards I have automatically extend the warranty. The credit card might pick up the repair for you.

Thank you
Russell

I wish I did. I used an ATM card that doesn't have that benefit. Why worry? I was buying a premium, professional quality zoom lens from Pentax. Over 30 years experience with Pentax without any problems. That's why I picked that lens over the Sigma or Tamron 70-200 2.8's. I ended up with the lighter lens, but with manual focus (literally 13 months later).

Has anyone successfully gone back from revision 1.3 to 1.2 (or earlier) on a K10D to get around this problem? If yes, how did you get back to the earlier revision?I've tried simply installing Ver 1.2, but it won't go.

Thanks,
Brian

[Russell-Evans]

Has anyone successfully gone back from revision 1.3 to 1.2 (or earlier) on a K10D to get around this problem? If yes, how did you get back to the earlier revision?I've tried simply installing Ver 1.2, but it won't go.

There is a modified 1.1 firmware that simply is a hex edit of the file that identifies the file as a 1.3 version. The camera reads this to decide if you can install the firmware or not, but uses a different location in the firmware to decide what the firmware really is once installed.

Once the modified 1.1 is installed, you can overwrite it with the official 1.1 firmware, or go up to the 1.2 firmware.

You can find more information here: Vietzon.com Forums

Thank you
Russell

[Russell-Evans]

Well Russell, you're making a lot of assumptions with regards to your guesstimates on numbers. Even then, the absolute numbers of SDM failure don't appear high.

Anyway just so you know, the number of Pentax users in Singapore is most certainly greater than 50... (the pitfalls of making simplistic assumptions based on group photos posted)

I'm not making any assumptions about the numbers. 75 is 0.1%, 1%, 10%, of the numbers given. If you think there are 75,000 SDM lenses owned by the people that post on DPR, then more power to you. If you think there are 7500, well, good for you. If you think there are 750 or less, then you really need to rethink your assumptions.

While you state there are more than 50 members to your group, you didn't answer the real question of how many SDM lenses are actually owned. If you can't answer that, then your pronouncement of the extent of the issue is about as good as your understanding of 1st grade math.

Thank you
Russell

[creampuff]

I'm not making any assumptions about the numbers. 75 is 0.1%, 1%, 10%, of the numbers given. If you think there are 75,000 SDM lenses owned by the people that post on DPR, then more power to you. If you think there are 7500, well, good for you. If you think there are 750 or less, then you really need to rethink your assumptions.

While you state there are more than 50 members to your group, you didn't answer the real question of how many SDM lenses are actually owned. If you can't answer that, then your pronouncement of the extent of the issue is about as good as your understanding of 1st grade math.

Thank you
Russell

You keep saying one thing but your previous posts are peppered with guesses/assumptions and estimates with no basis of proving anything.

No need to go off tangent and direct the discussion about the Singapore group. I don't owe you an explanation on percentages so don't talk rubbish about understanding 1st grade math, especially since you can't even provide conclusive proof of your own guesstimates.

I'll hazard a guess that I've met more Pentax users in person than you probably have. Most of those whom I know with SDM lenses haven't indicated they had a problem, and we know our local Pentax tech in person. To me that's a little more reliable than any online snap poll where it is harder to verify the issue with any certainty. BTW just wondering if you have owned any SDM lenses yourself?

[Bart]

When I get bitten by this SDM failure, I really couldn't care less about the odds!

The fact that this problem exists and that Pentax chooses to ignore it, is for me sufficient grounds to decide to never - ever buy another SDM lens.

And don't get me started on decentering.

[Russell-Evans]

You keep saying one thing but your previous posts are peppered with guesses/assumptions and estimates with no basis of proving anything.

Are we talking about me or are we talking about 75 failed lenses?

No need to go off tangent and direct the discussion about the Singapore group. I don't owe you an explanation on percentages so don't talk rubbish about understanding 1st grade math, especially since you can't even provide conclusive proof of your own guesstimates.

You're the one that keeps bringing up the numbers of the Singapore group proving that there is no issue. If you consider that tangential to your argument, then you don't understand WTF you are talking about.

I'll hazard a guess that I've met more Pentax users in person than you probably have. Most of those whom I know with SDM lenses haven't indicated they had a problem, and we know our local Pentax tech in person. To me that's a little more reliable than any online snap poll where it is harder to verify the issue with any certainty. BTW just wondering if you have owned any SDM lenses yourself?

If you are going to keep bringing up the number of people you have met with SDM lenses, then provide concrete numbers. 1,2, many, is BS.

Thank you
Russell

[creampuff]

Russell, so if I tell you I personally know five Pentax users off hand who have between them 11 SDM lenses and none have issues that is better than using the term "many"?

Well since you're the one starting the name calling, it is pretty clear that the one who is full of BS is you. You can't even back up your estimates with certainty nor refute the possibility of multiple postings to inflate the numbers. Plus the poll on this thread is so flawed and skewed to be meaningless. So by your tally it is 75 or so failures worldwide... big numbers indeed.

[PentaxPoke]

Russell, so if I tell you I personally know five Pentax users off hand who have between them 11 SDM lenses and none have issues that is better than using the term "many"?

Just to add some more relevent data to this discussion: 100% of the Pentax users I know personally have had SMD problems.

[glanglois]

Just to add some more relevent data to this discussion: 100% of the Pentax users I know personally have had SMD problems.

I've been studiously avoiding commenting here but my self-discipline is in tatters.

100% of what number ??

I take no position here and I won't make any assumptions/comments based on your answer. But it's like not hearing the punch line of a joke.

[Russell-Evans]

You can't even back up your estimates with certainty nor refute the possibility of multiple postings to inflate the numbers. Plus the poll on this thread is so flawed and skewed to be meaningless. So by your tally it is 75 or so failures worldwide... big numbers indeed.

I'm not sure where you are getting worldwide? The data is 75 failed lenses on DPR. DPR is not "the world".

The number of lenses counted comes from collecting all the individual posts I could find mentioning SDM issues with lenses and then looking through the posts to find what lens or lenses were mention in the posts. If you notice, I included links to the posts so that anyone can verify or discount any that they choose to. I would expect intelligent people to go through the posts and determine the issue for themselves.

I collected this information because I got tired of people posting the same flawed arguments about the issue.

1. The issue only affected a small number and those affected were vocal and repeatedly posting.
2. The people posting were just new members logging on to post the failure.
3. The issue was only: the first lenses, a small batch of bad parts, dirty contacts, abuse, ...
4. The issue had been "fixed" in later versions.
5. The issue was only in the 16-50mm and 50-135mm.
6. The primes didn't have failures.
7. The number of failed lenses are driven up by bodies causing the failures on multiple lenses.
8. It is the dual drive that is causing the issue.
9. I'm sure there are more, but I've forgotten as I didn't think people would still be trying to use them.

So your sample size is eleven lenses. That is pretty small as one lens represents about 10%. I hope your and your friend's good luck continues.

Thank you
Russell

[Donkeypunch]

Of course, take this with a grain of salt, because he is just a phone operator/customer service rep at Pentax. I called out Pentax today to check the status of my 16-50* SDM AF repair, as my certified factory repair place coudn't fix it, they sent it to Pentax. I started a conversation after I found out the status of the lens in regards to Pentax giving people the option on the K7 to select either screw drive or SDM, as I told him it is pretty unneeded on the 16-50 as it is a "Landscaper's" Lens. If I had the option to select screw drive, I wouldn't have even worried about sending it in, and I have no other body that I can use the lens on currently. Also make this option available on the K20, and a firmware "downgrade" for K10D owners. Seems like they still don't want to admit that SDM reliability is crap over the long term. I love everything else about the lens, except the SDM. I told him he should forward this conversation up the chain so people above him hear that it is a problem, and something they should address with firmware. He said he would bring it up. Granted like I said, he is just customer service, so I am not expecting him to move mountains, but hopefully someone hears about it. I would sure love it if crap didn't break right after the warranty ran out.

-Andy

[calicojack]

<snip> Also make this option available on the K20, and a firmware "downgrade" for K10D owners. Seems like they still don't want to admit that SDM reliability is crap over the long term. I love everything else about the lens, except the SDM. I told him he should forward this conversation up the chain so people above him hear that it is a problem, and something they should address with firmware. <snip> I would sure love it if crap didn't break right after the warranty ran out.

-Andy

I agree. My 50-135 stopped functioning (SDM) in month 13. I use a K10D that was upgraded prior to buying the lens. Through these forums i was led to a site (vietzone ??) that had a hacked firmware to revert my camera back to V1.1. I then upgraded to the official firmware V1.2. Now my 50-135 works just fine using the SD system.
Too bad I can't do something similar on my wife's K200D.

[Russell-Evans]

Creampuff, looks like you missed one.
https://www.pentaxforums.com/forums/1020667-post3.html

Thank you
Russell